Abstract in English:

ABSTRACT The objective of this study was to analyze dairy farm characteristics as a function of milk urea nitrogen (MUN) content in the north and west of the state Paraná, Brazil. Milk urea nitrogen serves as an indicator of protein utilization by cows. In view of the high costs of protein in animal diets, this study evaluated farm characteristics that could influence MUN content. For this, 32 dairy farms were randomly selected for application of a questionnaire assessing qualitative and quantitative variables. Interviews and samplings of bulk tank milk were carried out from October 2018 to October 2019. Three clusters of farms were identified: cluster 1, low MUN content (8.07 mg/dL); cluster 2, high MUN content (21.60 mg/dL); and cluster 3, intermediate MUN content (11.90 mg/dL). Clusters 1, 2, and 3 comprised 19, 4, and 9 farms, respectively. No association was found between MUN content and production system (conventional or agroecological). However, clusters differed significantly (P<0.05) in total number of cows and number of lactating cows. Differences (P<0.05) were also found for milk fat and total solids contents. As MUN is highly influenced by diet protein levels and the analyzed farms used feed based on the same ingredients (corn and soybean), it was not possible to identify which factors influenced MUN content for the studied farm groups.

Abstract in English:

ABSTRACT The aim of the study was to develop an index to measure sustainability in production systems. This sustainability index (iSus) was developed to be adhered to the Brazilian Pampa biome based on experts’ perceptions, in five regions of the Brazilian Pampa biome: Western border, Northwestern border, Campanha, Central, and South. The Sustainability Assessment of Food and Agriculture Systems guidelines, developed by the Food and Agriculture Organization, were used as reference for the indicators that formed the iSus. After selecting the indicators, a predefined list of experts was consulted to rank their priorities according to the analytic hierarchy process methodology. An electronic form was developed and sent to experts from each region assess the priorities of the dimensions, themes, and indicators. The selected dimensions did not differ, demonstrating that in the experts’ perception, no dimension has priority. Among the themes, investment (economic dimension), human health and safety (social dimension), and land and water (environmental dimension), were prioritized within the dimensions. In the analysis of indicators, there were no differences between the experts' perceptions and the regions analyzed. Indicators could be classified into groups of high, medium, and low priority. Water management, safety and health training, and net revenue were ranked as the highest priorities by the experts. The prioritization, together with the incorporation of an iSus, can contribute to broad actions to enhance sustainability in agricultural production systems. The use of the index will allow the measurement and identification of the basic premises of sustainability could be measured and identified.

Abstract in English:

ABSTRACT The objective of this work was to analyze the impact of different feeding frequencies on the growth and hematological parameters of freshwater fish species (tambaqui, Colossoma macropomum; matrinxã, Brycon amazonicus) subjected to biofloc technology enriched with sodium chloride. We tested two feeding frequencies: T1 = feeding all experimental days for tambaqui, except on Sundays; T2 = feeding all experimental days for tambaqui, except on Sundays and Wednesdays; M1 = feeding all experimental days for matrinxã, except on Sundays; and M2 = feeding all experimental days for matrinxã, except on Sundays and Wednesdays. The growth performance of tambaqui and matrinxã were not affected by the treatments. The MCHC for matrinxã was the only hematological parameter significantly different. The physiological status (Kn = condition factor) of the M2 treatment was the only parameter that presented a significant difference in relation to the central value (Kn = 1.00). Water quality parameters remained within the range indicated for the rearing of both species. The feeding frequencies tested do not negatively affect tambaqui or matrinxã.

Abstract in English:

ABSTRACT This study evaluated the potential for rearing matrinxã (Brycon amazonicus) with different crude protein (CP) levels and using production performance, water quality, and animal welfare as indicators. To achieve this, 720 juvenile fish (3.65±0.17 g) were distributed in 24 experimental units (200 L). The study, which lasted for 60 days, followed a factorial design (2 × 4) with two production systems: biofloc technology (BFT) and clear water (CW) and four CP levels (24, 30, 36, and 42%) in the diet, with three repetitions for each. We found that the BFT system showed a lower total ammonia level (0.45±0.15 mg/L) compared with CW (1.16±0.50 mg/L). Fish produced in the BFT system exhibited better performance in terms of apparent feed conversion (1.06±0.15), productivity (7.68±2.38 g/m3), and survival (76.95±9.15%). The type of production system affected total leukocytes and neutrophils in the blood. Juvenile matrinxã can be fed a diet containing 30% CP in both production systems. Furthermore, the results demonstrated that bioflocs do not confer a direct benefit to juvenile matrinxã in terms of their feeding; however, the BFT system is a promising alternative for increasing the survival and improving animal welfare during the rearing phase.

Abstract in English:

ABSTRACT This study evaluated the dietary supplementation of Cymbopogon flexuosus essential oil (CFEO) nanoemulsion in the cutaneous and branchial morpho-adaptive response and its antioxidant potential for silver catfish juveniles naturally infected by Aeromonas hydrophila. Four hundred silver catfish juveniles were randomly distributed in a water recirculation system and fed diets supplemented with CFEO nanoemulsion at concentrations of 0, 0.25, 0.5, 1.0, and 2.0 mL/kg of diet for 25 days. At the end of the experiment, skin, liver, and gill samples were collected for morphometric and oxidative status analyses. Our results showed that the highest concentrations of CFEO nanoemulsion (1.0 and 2.0 mL/kg) did not exert a structural preservation effect on the gill and cutaneous morphometry of animals naturally infected by A. hydrophila. However, the supplementation of 0.5 mL/kg of CFEO nanoemulsion demonstrated an antioxidant effect on their gills. In addition, dietary supplementation with CFEO nanoemulsion protected the liver of silver catfish against liver damage. Thus, due to these beneficial effects, CFEO nanoemulsion shows promising use in aquaculture.

Abstract in English:

ABSTRACT This study assessed the impact of varying dietary methionine (Met) and digestible energy (DE) levels on the growth performance, feed utilization, and glycemia in hemolymph of juvenile Penaeus vannamei reared under hyperosmotic salinity (43-48 g L−1). A 2 × 3 factorial design was used to evaluate six diets, varying in two DE levels (15.7 and 16.6 MJ kg−1, DM basis), achieved through soybean oil addition, and three Met levels (7.6, 8.5, and 9.9 g kg−1, DM basis), adjusted with crystalline DL-Met-Met supplementation. Dietary crude protein was maintained at 371 ± 3.0 g kg−1 (DM basis). Shrimp of 2.9 ± 0.04 g were reared at 100 animals m−2 in forty 0.5-m3 tanks for 60 days. No differences were found in shrimp survival, specific growth rate, weight gain, and feed conversion ratio (FCR) across the different DE and Met levels (P>0.05). However, dietary DE levels significantly influenced daily gross energy intake (P<0.01) and daily DE intake (P<0.01). Dietary Met levels significantly affected daily Met intake (P<0.01) and total sulfur amino acid intake (P<0.01). Glucose concentration in shrimp hemolymph was significantly influenced by dietary Met levels (P = 0.02), with higher levels leading to increased glucose concentrations. Results suggested that while Met levels affect certain metabolic responses, they did not translate into enhanced growth performance under hyperosmotic conditions. Experimental diets met the shrimp's dietary requirements for energy and Met, with no additional benefits observed from increased levels.

Abstract in English:

ABSTRACT The current study aimed to identify the variables that best explain performance using Principal Component Analysis (PCA), in addition to detecting gastrointestinal proteins, amylase, and lipase in juvenile tambaqui (Colossoma macropomum) fed diets with lysine. The diets contained 6.60, 9.72, 12.84, 15.96, 19.08, and 22.20 g.kg−1 of total lysine and were supplied to the fish (n = 180; 10 fish per tank) for 90 days. The data that were inserted into the productive performance equations were collected during the experimental period to perform the PCA. At the end of the 90 days, the fish were anesthetized, and gastrointestinal tissues were collected for analysis of protein concentration and enzymology. As a result, PCA showed that PC1 and PC2 (components 1 and 2) explain 80.40% of the performance. In PC1, the highlighted variables were feed and protein efficiencies and final weight, contributing 19.59, 17.31, and 17.12%, respectively. In PC2, the variables that contributed most were dietary intake (14.06%) and weight gain (13.42%). The previously mentioned variables showed high projections in the regression analysis (P<0.001). Gastrointestinal proteins varied; however, it was not possible to detect through post-hoc tests which diets influenced them (P>0.05). Enzyme activities did not vary (P>0.05). Feed efficiency is the variable with the most significant contribution to PC1, and diets containing up to 22.20 g.kg−1 of lysine do not influence gastrointestinal proteins nor amylase and lipase enzymes in juvenile tambaqui.

Abstract in English:

ABSTRACT This study assessed the nutrient profiles of major grower shrimp feeds in Brazil used in semi-intensive farming of Penaeus vannamei and their impact on shrimp growth under optimal (15.8 ± 0.14 ppt), hypoosmotic (3.9 ± 0.57 ppt), and hyperosmotic (41.8 ± 0.62 ppt) salinities. Juvenile shrimp (0.85–1.60 g) were stocked at 50 animals/m2 in 40 outdoor tanks (1 m3) and fed across three consecutive trials lasting 63 to 86 days. Dietary nutrient composition varied widely, with crude protein ranging from 38.2 to 41.2%, carbohydrates from 28.5 to 43.8%, crude fat from 6.7 to 12.1%, and ash content from 10.7 to 20.2%. There were also variations in gross energy (16.2–18.5 MJ/kg), macrominerals, amino acids (AA), and essential fatty acids (EFA). Principal Component Analysis and hierarchical clustering identified EFA, AA, and minerals as key factors driving feed variability. Growth performance under optimal and hypoosmotic salinities was largely attributed to EFA levels. Feed E, with the highest EFA content, supported superior growth, followed by feeds D and A. This ranking (feed E > feed D > feed A > feed F, feed B, and feed C) aligned with observed growth, highlighting the critical role of EFA in shrimp performance under these salinities. Under hyperosmotic conditions, shrimp growth was similar across most feeds, indicating high salinity limited growth. The study suggests that specific nutrient profiles, particularly those enriched in EFA, support growth more effectively under optimal and hypoosmotic conditions, while others are less effective under high salinity stress. The findings emphasize the need for adaptive feed formulations to meet metabolic demands, offering valuable insights for feed selection in regions with suboptimal salinity conditions.

Abstract in English:

ABSTRACT This study evaluated the effects of dietary crude protein (CP) and methionine (Met) levels on growth performance, feed utilization, and daily nutrient intake of juvenile Penaeus vannamei reared under 16 and 40 psu. A 2 × 3 × 2 factorial design tested six diets with CP levels (33.3 and 37.4%, as-is basis) adjusted via soy protein concentrate, and Met levels (0.6, 0.7, and 0.9%, as-is basis) supplemented with DL-methionine. Shrimp of 1.49 ± 0.11 g were fed for 91 days in 92 tanks of 0.5 m3 at 140 animals/m2. Salinity was the dominant factor affecting shrimp performance, significantly influencing survival, with higher rates observed at 40 psu (95.5 ± 4.5%) compared with 16 psu (90.7 ± 5.7%). However, a higher salinity negatively impacted final body weight (13.6 ± 1.2 vs. 11.4 ± 0.7 g), yield (13.8 ± 0.9 vs. 16.9 ± 1.6 MT/ha), weight gain (665.5 ± 44.5 vs. 816.1 ± 84.0%), specific growth rate (2.24 ± 0.06 vs. 2.43 ± 0.10%/day), and feed conversion ratio (1.46 ± 0.10 vs. 1.32 ± 0.08). Except for daily feed intake, shrimp reared at 16 psu consistently outperformed those at 40 psu (P<0.001). Dietary CP and Met levels did not significantly affect survival, yield, or other growth parameters (P>0.05), though raising CP and Met levels significantly increased daily CP and Met intake (P<0.001). Although shrimp at 40 psu showed increased intake of CP, Met, total sulfur amino acids, and total amino acids, this did not improve growth performance or feed utilization under hyperosmotic conditions. These findings suggest that elevated energy demands for osmoregulation in hyperosmotic environments limited nutrient conversion into growth, showing that dietary interventions were insufficient to fully overcome the challenges posed by high salinity.

Abstract in English:

ABSTRACT This research aimed to evaluate the chemical composition and apparent digestibility coefficients (ADC) of dry matter (DM), gross energy (GE), crude protein (CP), and amino acids (AA) in plant and animal protein sources used in aquafeeds for tambaqui (Colossoma macropomum). Tested ingredients were soybean meal (SBM), cottonseed meal (CSM), corn gluten meal (CGM), fish meal (FM), meat and bone meal (MBM), and poultry by-product meal (PBM). A reference diet was formulated to contain 287 g kg−1 CP and 18.5 MJ GE kg diet−1, and test diets were produced by incorporating test ingredients in a 70:30 ratio. Chromic oxide (Cr2O3) was used as an inert marker at 2 g kg−1, and feces were collected by sedimentation. High variation in the ADC of DM (0.577 to 0.958) and GE (0.506 to 0.953) was observed between protein sources, while the ADC of CP was higher and showed less variation between the ingredients (between 0.834 and 0.978). The CGM, FM, and PBM treatments had the highest ADC values and appeared adequate for compounding aquafeeds for tambaqui, while CSM and MBM showed the lowest ADC values. Interestingly, the ADC of AA was variable among ingredients (from 0.272 to 0.989) and did not show the same trend as the other nutrients (mainly the CP). The present study demonstrates that tambaqui can efficiently digest both plant and animal protein sources. However, overall digestibility of plant protein sources appeared lower when extrusion was used to manufacture the diets.

Abstract in English:

ABSTRACT The objective was to describe the organizational structure of the Mangalarga herd and evaluate the influence of geographic distribution and different coats on the population structure and genetic diversity. Genealogic data of horses born between 1919 and 2018 were submitted to the software ENDOG 4.8, corresponding to the total population (TP), and those born between 2009 and 2018, representing the reference population (RP). Wright’s fixation index, inbreeding coefficient (F), and average relatedness (AR) were estimated considering each Brazilian state as a subpopulation and, afterwards, the different coat colors as subpopulations. The origin and use of breeding animals were used as parameters to classify the populations in the different states within the strata: Nucleus, Multiplier, Commercial, and Isolated. Considering Brazilian states as subpopulations, the mean value estimated for FIS in the RP was 0.0091, FIT of 0.0107, FST of 0.0016, F of 5.81%, and AR of 3.81%. In the RP, the sorrel coat accounted for 87.58% of the genetic contribution. Considering different coat colors as subpopulations, the mean value estimated for FIS in the RP was 0.0103, FIT of 0.0107, FST of 0.0004, F of 3.53%, and AR of 3.29%. In the RP, the breed is present in 14 states. Of those, 53.33% were classified as Multiplier herds and 46.67% as Commercial herds. The organizational structure of the Mangalarga breed is not pyramid shaped and, even with the greater genetic contribution of the state of São Paulo and of the sorrel coat, the inbreeding coefficient is under control.

Abstract in English:

ABSTRACT The objective of this study was to evaluate which morphometric variables have the greatest influence on the conformation differences observed in a subpopulation of adult Mangalarga Marchador (MM) horses and to summarize these traits through calculated scores (PCA eigenvectors) to later compare with the scores obtained by these animals during the act of registration. Forty-six morphometric traits were used, which included the 12 mandatory measures of the definitive genealogical registration and two of these new ones: “triangle” and the “Z” of the gait. We used 273 adult MM horses with known genealogy. In addition, their weight and 11 indexes used for functional analysis were calculated. Gait and morphology scores were provided by the Associação Brasileira dos Criadores do Cavalo Mangalarga Marchador (ABCCMM). Initially, the correlations between linear morphometry, angular morphometry, live weight, and functional indexes were analyzed separately. There was a greater proportional reduction of variables among linear measurements (from 32 to 15) than angular traits (from 12 to 7), which did not occur for weight and all the indexes. The low association between PCA scores and the subjective scores for morphology and gait at the registration, coupled with the fact that only six of the 12 mandatory linear measurements were related to the variability of the studied animals, suggests a review of the current registration system to improve sensitivity in the search for phenotypic traits of interest to maintain the current breed standard.

Abstract in English:

ABSTRACT The objective of this study was to identify how linear-type traits impact the culling risk and which traits are most associated to productive life of Holstein cows. Linear classification and test-day milk yield data of 34,653 primiparous cows obtained from the database of Associação Paranaense de Criadores de Bovinos da Raça Holandesa were used. Survival analysis was performed by PHREG procedure of SAS/STAT 9.4 using a Cox regression model. The model considered herd and year of the linear classification (2010 to 2019) as fixed effects and the linear effects of 305-day cumulative milk yield in first lactation (kg), age at first calving (months), the individual traits, and final score as covariables. Cows with intermediate rump angle (score 6) had the lowest culling risk. The culling risk for cows with inverted rumps (score 1) was four times greater than for cows with inclined rump (score 9). Females with moderately curved rear legs, side view, were more likely to remain for a longer period in the herd. Cows with extremely high and strongly attached udders had the lowest culling risk (1.0). Classification at first calving may be a strong indicator of long productive life of Holstein cows. Females rated as Good Plus or Very Good tend to remain in the herd longer. The traits of the mammary system have the most impact on the length of productive life.

Abstract in English:

ABSTRACT The objective of this study was to unravel the genetic architecture of growth traits in sheep through a meta-analysis of genetic parameters (i.e., direct, maternal, and total heritability estimates, as well as genetic correlations), a systematic review, and a functional analysis to identify candidate genes and metabolic pathways related to growth traits. A random effects model was used to obtain the pooled effect estimates for the genetic parameters, and heterogeneity was assessed using both I2 and Cochran’s Q statistics. For the systematic review, genomic regions were searched in the selected scientific papers, and genes were identified using the Biomart tool. After quality control, 118 articles comprising nine traits, 504 heritability estimates, and 74 genetic correlation estimates were used for the meta-analysis, and 14 articles remained for the systematic review of the genomic regions. The pooled direct heritability estimates across studies ranged from 0.07 (±0.04) for weaning weight to 0.29 (±0.03) for weight at nine months. The systematic review identified 461 genes in the significant genomic regions. These genes were distributed across all chromosomes, with most of them located on OAR11. Some regions on chromosomes 6, 15, and 21 exhibited pleiotropic effects across traits. Pathways were mainly associated with developmental and lipid metabolic processes. Growth traits in sheep are complex, have low to moderate heritabilities, and are influenced by several genes of small effect, some of which of pleiotropic effect.

Abstract in English:

ABSTRACT This study aimed to evaluate genotype × environment (G×E) interactions in Guzerá breed animals for 305-day first-lactation cumulative yields (kg) of milk (MY305), fat (FY305), and protein (PY305). We used 6823 records of MY305, 2466 records of FY305, and 1870 records of PY305. The contemporary groups (CG) were created considering herd and year of calving. The analyses were performed in two steps. In the first step, environmental effects on phenotypes were estimated by using a multi-trait model ignoring G×E interactions. In the second step, G×E interactions were evaluated by using single-trait analyses with the reaction norm model and considering heterogeneous residual variance divided into five classes. The CG solutions obtained in step 1 were used as an environmental gradient in step 2, representing low to high management environments. We observed increasing genetic variance estimates along the environmental gradient for all evaluated traits. Residual variance showed the same pattern, except with class 5 of FY305 and class 4 of PY305. Heritability estimates increased slightly as the management level increased. The correlation estimates between the intercept and the slope of the reaction norm curve were 0.998 for MY305, 0.989 for FY305, and 0.987 for PY305. The genetic correlation among the low (5% quantile), medium (55% quantile), and high (95% quantile) management level environments was high, with values higher than 0.99, 0.97, and 0.70 for MY305, FY305, and PY305, respectively. The breeding values of the animals changed along the environmental gradient, even those classified as robust. These results demonstrate a G×E interaction with scale effect for the evaluated traits that affects the breeding values.

Abstract in English:

ABSTRACT The objective of this study was to evaluate the associations among forage production related traits in Paspalum nicorae Parodi ecotypes and employ BLUP multi-trait path analysis as a selection criterion. Eighty-four ecotypes were grown in a randomized block experimental design with four replications and measured for three years. Measurements included number of tillers, fresh matter, leaf dry matter, stem dry matter, inflorescence dry matter, total dry matter, leaf:stem ratio, harvest index, cold tolerance, forage persistence, growth habit, and plant height. Variance components were estimated using maximum residual likelihood, and genetic correlation coefficients were obtained from the output of a mixed model. Subsequently, path analysis was performed, which used total dry matter as the dependent trait. Total dry matter showed positive and significant associations with most of the traits studied. This meant that indirect selection based on the number of tillers, height, and total fresh matter was a viable method to select for increased dry matter production. Multi-trait path analysis based on BLUP proved to be useful for studying associations between traits related to total dry matter and demonstrated that leaf dry matter has the greatest direct effect on total dry matter.

Abstract in English:

ABSTRACT This study aimed to describe the phenotypical and biometrical characteristics of Creole goats on the Tamaulipas Plateau (TP) and San Fernando Valley (SFV) agroecological zones in northeastern Mexico. Eight hundred fifty-eight goats (70 males and 788 females) were studied to collect qualitative and quantitative information. Data were analyzed for male and female goats separately using frequency and general linear models. Pearson’s correlation was used to analyze linear body measurements (LBM) for morpho-structural homogeneity. The canonical discriminant analysis and a multiple correspondence analysis were made for examined the presence of any subpopulations on seven municipalities of the two districts. The northeastern Mexican Creole goats are light-colored with arched horns, large pendulous ears, convex cephalic profile, and dual-purpose productive aptitude. Live weight was higher in SFV than in TP female goats (35.4 + 4.4 kg vs. 30.3 + 4.6 kg, P = 0.0001). No weight differences were observed between male goats. More than 65% of the LBM correlations (regardless of sex or agroecological zone) were positive, indicating balanced physical growth and environmental adaptation. The Creole goat breed predominance in both goat ecotypes is primarily of African origin. The multivariate analysis showed dissimilarities between SFV and TP, but similarities among the sampled localities in each district. Additionally, the morpho-structure of the TP goats is adequate for a dual purpose, whereas the SFV goats are adequate for kid meat production. This study could be complemented by molecular characterization, which could describe the northeastern Mexican Creole goat based on specific genetic background.

Abstract in English:

ABSTRACT The INTERGEN package has been under constant development for the last two decades using the Fortran 90/95 programming language. The latest version of INTERGEN includes three different binaries: intergen, intergeniod, and intergenacc. Intergen has been consistently expanded to include the Best Linear Unbiased Prediction (BLUP) genomic module in recent years. The intergeniod and intergenacc binaries are new and aim to estimate genetic merit using iteration on data (IOD) and approximate accuracy. The present study aimed to provide a high-level overview of INTERGEN functionalities and to assess the reliability of the IOD genomic new module included in the intergeniod. Single-step GBLUP (ssGBLUP) models using beef cattle growth and conformation traits were used to estimate breeding values using intergeniod and compared with benchmarking software (intergen). The rank correlation for the breeding values between intergeniod and intergen was equal to the unit. The INTERGEN package can be applied to the genetic analysis of large-scale datasets using intergen, intergeniod, or intergenacc.

Abstract in English:

ABSTRACT The present study aimed to evaluate the effectiveness of the grain processing carried out by a device containing round and oblong holes attached to the inside of the forage harvester and evaluate its impact on the nutrient composition of corn silage, animal productivity, feeding behavior, apparent digestibility of the diet, and carcass traits of feedlot finished steers. The silages tested were: silage subjected to the grain processor (SGP) and silage not subjected to the grain processor (SNGP), which also made up the diet given to the animals. For animal assessment, we used 32 crossbred steers (half Angus, half Nellore), with an average age of 11±2 months and an initial average body weight of 350±9.06 kg. The experiment was a randomized block design, consisting of two treatments and eight repetitions each, represented by a pen with two animals. The SGP showed a greater accumulation of grains at the bottom of the particle separator system, that is, the processor promoted a reduction in particle size, which led to a 42% higher starch content in the lower layer. At the end of the 112 days of evaluation, the animals that received the diet composed of SGP achieved higher daily weight gain (1.627 kg/day) than those fed SNGP (1.427 kg/day), better feed efficiency, and higher carcass gain during the experimental period (116.3 vs 105.5 kg). The use of the grain processing system improves the use of the diet by the animals and makes a greater fraction of starch available, resulting in higher animal weight gain.

Abstract in English:

ABSTRACT We aimed to evaluate the effects of storage condition (SC) and storage time (ST) on the fermentative parameters and nutritional value of relocated whole-plant corn silage (WPCS) in plastic bags. A completely randomized design was used in a 2 × 5 factorial arrangement, with two SC (in the field without cover and in a barn as covered space) and five ST (10, 30, 60, 90, and 120 d), with four replications. Corn was harvested (321 ± 10.3 g kg−1 dry matter (DM)) and relocated in plastic bags (50 kg) after 210 d of fermentation. The mold count of silage stored in the barn displayed a quadratic adjustment (P = 0.008) and reached its lowest value at 60 d of storage. Yeast count decreased (P = 0.001) linearly as a function of time in the silage stored in the barn. Lactic (P<0.001) and acetic (P<0.001) acid concentrations increased linearly as a function of silage ST in the field. A quadratic relationship was observed between protein concentration (P = 0.039) and in vitro dry matter digestibility (IVDMD; P<0.001) and ST for silage in the field, with the lowest value observed at 90 (58.3 g kg−1 DM) and 60 (529.3 g kg−1 DM) days, respectively. The concentration of ammonia nitrogen increased linearly by 6.80 g kg−1 TN (P<0.001) as a function of ST in relocated silage in the field. The IVDMD increased linearly (P<0.001) as a function of time in silage stored in the barn. Silage in the field had 1.00 log CFU g−1 more lactic acid bacteria (LAB) than those stored in barns. A quadratic adjustment was observed (P<0.05) as a function of ST on LAB count, aerobic stability, maximum temperature, time to reach maximum temperature, DM, and organic matter. It is recommended that silage be stored in bags in the field for use within 60 d. Silage stored in bags in a barn can be used within 120 d.

Abstract in English:

ABSTRACT This study aimed to characterize the response mechanisms and evaluate the resistance of Megathyrsus maximus hybrids to water deficit and waterlogging. The experiment was conducted in a greenhouse using a randomized block design with an 8 × 3 × 2 factorial arrangement. Treatments were a combination of eight genotypes of M. maximus, three water conditions (control, waterlogging, and water deficit), and two harvest times (20 days of water stress and 12 days post-recovery). Productive and morphological traits were evaluated at the end of the stress period and after the recovery period. All hybrids subjected to water deficit showed reduced aerial and root mass. However, a survival response was observed post-stress, with recovery of approximately 28.4% of the aerial part and 16.3% of the root system in all genotypes. Hybrid PM409 showed potential for adaptation to waterlogging, as suggested by the observed greater root production (41.2%) compared with the average production of other genotypes. In addition, there was no reduction on leaf and stem mass production compared with the control condition. The results suggest that no material showed to be resistant to water deficit. On the other hand, hybrid PM409 showed promising traits for waterlogging stress resistance.

Abstract in English:

ABSTRACT The objective of this study was to evaluate the use of grazing management strategies (GMS) in rotational stocking to improve the canopy structure in mixed pastures of Marandu palisadegrass (Brachiaria brizantha cv. Marandu) and legume Macrotyloma axillare. Treatments consisted of combinations of defoliation frequencies (pre-grazing heights of 30 and 40 cm) and intensities (post-grazing heights of 15 and 20 cm) in a 2 × 2 factorial arrangement, corresponding to four GMS: 30-15, 30-20, 40-15, and 40-20 cm, allocated to 16 experimental units (paddocks) in a completely randomized block design with four replicates. Pastures managed with 30-20, 40-15, and 40-20 cm had the highest pre-grazing legume masses (P = 0.0378), but for all GSM, there was a reduction of legume in the forage mass over time (P<0.0001). In Summer 1, legume was observed in the upper strata of the pre-grazing profile for all GMS, but in Summer 2, it was only detected in the 20-25 cm stratum of the 30-20 and 40-20 cm GMS. Pastures managed with 30-20 cm had a high pre-grazing bulk density of total forage, grass, and legume leaf (P<0.05), and a high post-grazing grass leaf mass and bulk density. The highest pre- and post-grazing stem mass and bulk density occurred in pastures with a pre-grazing height of 40 cm (P<0.05). The lower defoliation frequencies (pre-grazing height of 40 cm) had no benefits for the canopy structure. Among the GMS evaluated, a pre-grazing height of 30 cm and a post-grazing height of 20 cm resulted in the most suitable canopy structure for grazing.

Abstract in English:

ABSTRACT The objective of this study was to assess the impact of incorporating vegetable oils into the in vitro fermentation of a tropical grass on the kinetics and digestibility of the fibrous fraction by rumen microorganisms. Treatments consisted of different inclusion levels (0, 2, 4, and 6% dry matter) of lipid sources, namely soybean oil, canola oil, and baru oil, mixed with tropical forage (Pennisetum purpureum Schum cv. Cameroon). A completely randomized design was employed, featuring a 3 × 4 factorial arrangement (three lipid sources at four inclusion levels), resulting in 12 treatments, each with three replications. We examined the kinetics of rumen fermentation using the semi-automatic in vitro technique of cumulative gas production. Oil inclusion levels had a significant impact on in vitro gas production and lag time (P<0.0001), with values decreasing as the oil inclusion levels were increased, with no effect of sources. Furthermore, the digestibility of forage neutral detergent fiber (NDF) was negatively affected by higher oil inclusion levels, with significant differences observed among the lipid sources tested (P<0.0013), with improved digestibility effect for baru oil. The production and profile of short-chain fatty acids were also influenced by oil inclusion level factors; however, the influence of different lipid sources was only evident in treatments with 6% inclusion. Baru oil can be a potential dietary alternative for ruminant supplementation in the intake of tropical forages, as it presented the lowest adverse effect on the in vitro digestibility of NDF among the lipid sources used, such as soybean oil.

Abstract in English:

ABSTRACT The objective of this study was to evaluate the LBu 01 - CGMCC 19250 strain of Lentilactobacillus buchneri (LB) in whole-plant corn silage (WPCS) during different storage periods. The experiment was conducted in a completely randomized design with a factorial arrangement of treatments (2 × 3), two inoculant levels (control – without inoculant, and experimental – inoculated with 9 log CFU LBu 01/kg of forage), and three storage periods (3, 15, and 62 days). Dry matter (DM) losses, aerobic stability, microorganism population, and nutritional composition were quantified. The pH was lower for the inoculated silage (3.68) than for the control silage (3.73) (P = 0.03). Dry matter loss was lower in LB silage (P<0.01) than in control silage after storage for 15 (6.3% control; 1.6% LB) and 62 (12.9% control; 4.8% LB) days. The digestibility of the NDF after 30 h of incubation was greater (P<0.01) in the inoculated silage (56.9% NDF) than in the control silage (54.9% NDF). At 62 days, the lactic acid concentration was greater in the control silage (9.64% DM) than in the inoculated silage (7.38% DM) (P = 0.03). At 62 days, the LAB population in the inoculated silage increased, and the aerobic stability was greater in the inoculated silage (42 h) than in the control silage (27 h). Silages inoculated with the L. buchneri LBu 01 strain showed promising results, mainly after 62 days of storage. This strain is recommended for use in whole-plant corn silage.

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ABSTRACT The current study evaluated the impact of aerobic exposure time (ET) and microbial inoculants (MI) on the fermentative and microbiological characteristics and the nutritional value of relocated whole-plant corn silage (WPCS). Treatments were arranged in a 4 × 5 factorial design: microbial inoculants (without inoculant (WI); L. plantarum (DSM3676; DSM3677) + L. buchneri (DSM13573) (LPLB); L. plantarum (MA18/5U) + P. acidipropionici (MA26/4U) (LPPA); and L. buchneri (DSM13573) (LB)) and non-relocated (NR) or relocated after 12, 24, 48, and 60 h of ET. In the NR silage, the total storage time was 120 (not exposed-ET 0 h) or 210 (NR) days. Fresh forage that included an inoculant was inoculated with 1 × 105 CFU g−1 of forage. Samples were collected after 120 days of ensiling at various exposure times, and again after an additional 90 days of fermentation. For the samples collected at the initial opening (120 days), exposure time was not included as a factor in the statistical model. After 120 d of ensiling, inoculated silage exhibited higher lactic and propionic acid and lower ethanol concentrations, lower yeast counts, and reduced dry matter losses. During exposure, yeast counts increased (P<0.01) in WI silages after ET 0 (3.50 CFU g−1) to 60 h (4.90 CFU g−1). Post-relocation, the mold counts in WI silage were greater (P<0.01) when NR (4.02 CFU g−1) and relocated at 12 h (4.1 CFU g−1) and 24 h (4.2 CFU g−1) compared with other silages. The in vitro dry matter digestibility of LB silage decreased (P<0.01) from NR (674.7 g kg−1 DM) to 60 h (592.6 g kg−1 DM). The LB silage exhibited reduced aerobic stability. L. buchneri inoculation enhances the digestibility of corn silage ensiled for 210 d, but the digestibility is reduced from 24 h of aerobic exposure.

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ABSTRACT This study evaluated the association of stearoyl-CoA desaturase (SCD) and fatty acid-binding protein 3 (FABP3) gene polymorphisms with carcass and meat quality traits in Aberdeen Angus bulls. Two hundred seventy-four Angus bulls were genotyped using PCR-RFLP and Sanger sequencing. Next, the association of SCD and FABP3 genetic variants with traits such as live weight, average daily weight gain, carcass weight (both hot and cold), dressing percentage, carcass length, back fat thickness, carcass color score, pH, and marbling score was analyzed. Significant differences were observed in average daily weight gain among different FABP3 genotypes, with the GG genotype showing the highest gains (P<0.01). Furthermore, novel associations between the SCD × FABP3 interaction and key traits were identified, including dressing percentage and carcass pH. Notably, an epistatic pattern through this genotypic interaction was demonstrated, which may significantly influence postmortem pH decline in beef cattle. The results suggest a notable impact of the FABP3 rs210042291 gene on growth rates. These findings highlight the complexity of genetic influences on meat quality traits.

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ABSTRACT The effects of diets containing various levels (0, 10, and 20%) of cottonseed meal (CSM) and enzyme mixture (0.1%) on quail serum iron, haemoglobin, and haematocrit values and colour values of breast meat were investigated. Four hundred fifty male and female Japanese quail chicks at one day of age were used, and these were divided into six treatment groups. The animals were fed six different diets: a control diet without CSM and enzyme mixture (CSM0−), a control diet without CSM but with enzyme mixture (CSM0+), a 10% CSM diet without enzyme mixture (CSM10−), a 10% CSM diet with enzyme mixture (CSM10+), a 20% CSM diet without enzyme mixture (CSM20−), and a 20% CSM diet with enzyme mixture (CSM20+). With increasing levels of CSM, haemoglobin and haematocrit values exhibited a linear decrease (P<0.01). The results revealed that the influence of CSM levels and enzyme mixture on various colour parameters of breast meat became apparent at different storage durations. However, this effect on the colour parameters did not exhibit consistency over time. It can be said that the diets containing 10 and 20% cottonseed meal with or without enzyme mixture have no negative effect on the meat colour of quail across different storage durations.

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ABSTRACT This study aimed to characterize carcass, meat quality, sensory and textural parameters, as well as muscle fiber types from 16 Moura pigs, as a local pig raised in outdoor production system, and evaluate differences with 16 conventional commercial (CC) pigs, raised intensively, representing the principal pork type, widely available in national market. Carcass measurements, liquid loss and cooked pork texture tests, proximal composition analysis of pork and backfat, and sensory evaluations with 104 pork consumers were carried out. The statistical arrangement used was bifactorial blocks: pork type and sex (2 × 2) in two blocks. Moura pigs had greater carcass lipid deposition and intramuscular fat (IMF) (3.51 vs 1.91 g/100 g) than CC pigs (P<0.01), while CC pigs had greater lean tissue deposition and drip loss (6.44 vs. 2.88%) (P<0.01). Moura pork backfat presented a higher luminosity and lipid content and lower moisture content, and red and yellow values than CC backfat (P<0.03), while Moura pork was darker and redder than CC pork (P<0.01). Moura pork had larger relative areas of oxidative (Ia) (11.19 vs. 7.32%) and intermediate (IIa) (22.81 vs 11.70%) muscle fibers, while CC pork had higher glycolytic fibers (80.98 vs 66.00%) relative areas (P<0.01). Hardness, gumminess, and chewiness parameters from CC cooked pork had higher values than moura pork (P<0.01). Panelists preferred cooked Moura pork (72 vs. 28%) to CC pork (P<0.01). Differences in backfat characteristics between CC and Moura pork are attributed to greater lipid backfat content in Moura pork. The greater proportion of Ia and IIa muscle fibers contribute to Moura pork color, combined with a greater IMF content and less liquid loss, contributing to greater tenderness and juiciness Moura pork, preferred by consumers.

Abstract in English:

ABSTRACT We determined the impacts of light intensity, fasting, and storage times on total protein (TP), albumin (ALB), globulin (Glb), uric acid (UA), creatinine (Cre), calcium (Ca), phosphorus (P), and alkaline phosphatase (ALP) in serum and plasma of broilers. At 42 days old, 140 broilers (3,123 ± 654 g) were assigned to two light intensities (5 or 20 lux m−2) and seven fasting times (0, 2, 4, 6, 8, 10, and 12 h). At 45 days old, blood collection was performed in all the broilers. Serum and plasma were stored in a freezer at −20 °C and analyzed on 0, 15, 30, 60, and 120 days. Higher concentrations of Cre and plasma Ca were observed at 20 lux, while the other components were observed at 5 lux. Serum ALB and Ca decreased with each hour of fasting, whereas ALP increased. Uric acid had the lowest concentration at 4 h and 51 min of fasting. Peak serum concentrations of Glb, TP, and Cre were at 6 h, 4 h and 30 min, and 5 h and 15 min of fasting, respectively. Plasma UA, Ca, and P had the lowest concentration at 3 h and 48 min, 5 h and 45 min, and 30 min of fasting, respectively, and a reduction in ALP. Serum UA, TP, and Glb concentrations increased with increasing storage time. Peak serum concentrations of Cre, P, and Ca were at 42, 119, and lowest at 82 days, respectively. Plasma Glb and ALP showed an increase with each storage day, while Cre decreased. Plasma UA and P showed the highest concentrations at 101 and 62 days, respectively. Plasma Ca showed a lower concentration at 50 days. The factors studied significantly influence key blood components in broilers. Higher light intensity increases Cre and Ca concentrations, while fasting reduces serum ALB and Ca, with variable peaks in other components. Storage boosts serum UA, TP, and Glb, with component-specific peaks and declines over time.

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ABSTRACT This study aimed to evaluate effects of an emulsifier based on glyceryl polyethyleneglycol ricinoleate in diets containing deactivated full-fat soybean (DFFS) on performance, relative weight of pancreas, pancreatic lipase activity, intestinal morphometry, serum lipid concentration, nutrient digestibility, carcass yield, and meat quality of broiler chickens. Three hundred fifty-two male broilers (one-day-old) were randomly assigned to two dietary treatments including a diet containing DFFS without the emulsifier and a diet containing DFFS with emulsifier (350 g ton−1). Each treatment had eight replicates with 22 birds each. The metabolizable energy level was reduced by 40 kcal kg−1 from 1 to 21 d and 50 kcal kg−1 from 22 to 49 d in diets containing the emulsifier. Birds fed diets without emulsifier showed higher weight gain (P = 0.014) and feed intake (P = 0.048) from 1 to 7 d and greater feed conversion ratio (P = 0.044) from 1 to 35 d. On days 14 and 21, the inclusion of emulsifier in the diet did not affect (P>0.05) the intestinal morphometry, relative weight of pancreas, and pancreatic lipase activity. Serum lipid levels measured at 14, 21, and 29 d were also not affected by the emulsifier (P>0.05). At 49 d, broilers fed diets without emulsifier had decreased energy utilization (P<0.0001) and ileal digestibility of dry matter (P = 0.0001), gross energy (P<0.0001), and crude protein (P = 0.038). A higher breast yield (P = 0.039) was observed for birds fed diets without emulsifier. Meat quality parameters were not altered (P>0.05). The inclusion of the emulsifier in energy-restricted diets containing DFFS does not improve performance of broiler chickens, reduces the ileal digestibility of nutrients, without changes in morphophysiological parameters or meat quality of broilers.

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ABSTRACT The objective of this study was to evaluate the effect of different sources of choline in the diet of laying Lohmann Brown hens (26 to 37 weeks of age) on productive performance, egg quality, and blood parameters. A completely randomized experimental design was adopted, consisting of five treatments, with eight replications and six birds per experimental unit. The treatments consisted of a basal diet without supplementation of any source of choline (NC); NC + supplementation with 939 mg/kg choline chloride 60%; NC + supplementation with 167 mg/kg Biocholine®; NC + supplementation with 83 mg/kg Biocholine DS®; and NC + supplementation with 300 mg/kg Biocholine DS®. The performance parameters evaluated included laying percentage, average feed intake, feed conversion ratio by mass and by dozen eggs, average weight gain, and egg mass. The egg quality parameters comprised the average weights of the egg, yolk, shell, and albumen, as well as the Haugh unit, yolk index, shell weight per surface area, yolk color, and average percentages of the constituent parts. Additionally, blood parameters were analyzed, including glucose, cholesterol, high-density lipoprotein, triglycerides, uric acid, glutamic oxaloacetic transaminase, creatine phosphokinase, and gamma-glutamyltransferase. No statistically significant differences were observed in any of the evaluated parameters, except for glucose levels, which were higher in treatment with 300 mg/kg Biocholine DS®. For hens fed diets based on corn and soybean meal, no effect on the performance and egg quality was observed due to supplementation with choline chloride 60% or herbal products that are sources of choline.

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ABSTRACT The objective of this work was to evaluate the composition of macro- and microelements in samples of bee honey (Apis mellifera) produced in different floral resources: aroeira (Myracrodruon urundeuva), cissus (Cissus rhombifolia), eucalyptus (Eucalyptus spp.), orange (Citrus sinensis), and honey of Jataí (Tetragonisca angustula). The content of macro- and microminerals in the honey samples were determined by inductively coupled plasma-optical emission spectrometry (ICP-OES). The results showed concentration levels of macro- (Ca, P, K, Mg, and Na) and microelements (Al, As, Cu, Fe, Mn, Ni, and Se) in the samples of honey analyzed. The present study revealed that there were Na concentrations in tested samples analyzed. Cadmium, Co, Cr, and Mo were not detected in any sample. The concentration of heavy metals such as As detected in the honey of A. mellifera and T. angustula were above the tabulated values. T. angustula honey had higher concentration of minerals when compared with A. mellifera honey, except for Fe, Mn, and Ni, in which aroeira honey had a higher concentration. Considering the determination of heavy metals, the study reveals that honey produced by bees can be excellent bioindicators of environmental pollution.

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ABSTRACT Pigs are susceptible to infections and inflammatory conditions throughout their life phases, requiring adequate nutrient intake to support immune defense functions. Trace elements such as zinc (Zn), selenium (Se), and copper (Cu) are crucial for immune competence and antioxidant defense. While nutritional guidelines define baseline requirements, the swine industry frequently adopts supranutritional levels of Zn, Cu, and Se to optimize health and performance. Therefore, this review explores the impacts of trace mineral supplementation (e.g., Zn, Cu, and Se) on pig health subjected to stressors such as heat stress, oxidative stress, and infections. Various experimental models replicate challenges faced on commercial farms, in which Zn supports immune function by stabilizing cell membranes, modulating cytokine expression, and strengthening the intestinal barrier through increased synthesis of tight junction proteins, which collectively help reduce inflammation and pathogen translocation. In turn, Cu contributes to immune defense via its bacteriostatic effects and its role as a cofactor in antioxidant enzymes like superoxide dismutase, which mitigates oxidative damage by neutralizing reactive oxygen species. Moreover, Se is essential for the synthesis of selenoproteins, which protect cells from oxidative stress by regulating redox reactions and enhancing glutathione peroxidase activity. These mechanisms, as demonstrated in recent studies, suggest that supplementing these trace minerals above standard dietary levels can significantly improve immune function, antioxidant defenses, and intestinal integrity in pigs, providing strategies to meet the physiological demands imposed by various stressors in pig production systems.

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ABSTRACT The objective of this study was to determine the optimal concentration of digestible methionine plus cystine (Met+Cys) for broiler chickens. We allocated 1,296 male broiler chickens in a completely randomized design with six treatments and nine replicates of 24 broiler chickens each. From 1 to 21 days old, broiler chickens were fed a basal diet. At day 21, the experimental diets were offered, which consisted of a basal diet (with no inclusion of synthetic methionine) and five diets supplemented with increasing concentrations of DL-methionine, which supplied 7.70, 8.29, 8.89, 9.48, 10.07, and 10.67 g/kg Met+Cys in the grower phase (21 to 35 d); and 6.92, 7.41, 7.90, 8.38, 8.87, and 9.36 g/kg Met+Cys in the finisher phase (36 to 42 d). Feed intake (FI), body weight gain (BWG), feed conversion ratio (FCR), methionine intake, efficiency of methionine utilization, carcass yield, breast yield, and abdominal fat percentage were recorded. The quadratic polynomial (QP) regression, segmented, linear response plateau (LRP), and broken-line regression (BL) statistics were used to calculate the optimal Met+Cys concentrations for BWG and FCR. In the grower phase, FI was not affected by the increasing concentrations of Met+Cys, but it was linearly reduced during the finisher period (P<0.05). Greater Met+Cys concentrations positively affected the other analyzed variables in every phase (P<0.05). During the grower phase, the QP and LRP models were better fit to the BWG data, respectively indicating 10.30 and 9.10 g/kg optimal Met+Cys concentrations, whereas the QP model estimated 10.03 g/kg Met+Cys for optimal FCR. For the finisher phase, LRP was a better fit to BWG and FCR data, respectively estimating 8.20 g/kg optimal Met+Cys concentrations.

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ABSTRACT This study investigated the effects of different beak trimming methods on the development, hematological parameters, cloacal temperature, beak length, egg quality, and laying performance of laying hens from 1 to 31 weeks of age. Nine hundred Lohmann White LSL-Lite laying hens were randomly assigned to three treatments based on beak trimming methods: infrared radiation, hot blade straight cut, and hot blade V-cut. Laying hens subjected to the hot blade V-cut method had lower feed intake, body weight gain, laying percentage, and egg mass compared with those subjected to the infrared method (P≤0.05), with no significant differences observed when compared to the hot blade straight cut method (P>0.05). Additionally, hens subjected to the hot blade V-cut method produced eggs with lower specific gravity and Haugh unit (P≤0.05). Furthermore, the hot blade V-cut method was associated with higher mortality rates between one and six weeks of age. No significant treatment effects were observed on the weight of lymphoid organs or cloacal temperature (P>0.05). Birds subjected to the hot blade V-cut method also exhibited shorter beaks at 31 weeks of age (P≤0.05). The hot blade V-cut method negatively affects birds' performance and increases early mortality, likely due to its aggressiveness, which may compromise the overall laying production performance.

Abstract in English:

ABSTRACT The objective of this study was to evaluate the coefficients of total tract apparent digestibility (CTTAD) of nutrients, fecal characteristics, intestinal fermentation products, and diet palatability in dogs fed xylanase-supplemented diets with inclusion of whole or defatted corn germ in two experiments. Experiment I - six adult dogs were distributed in a 6 × 6 Latin square in a 3 × 2 factorial scheme with the experimental diets: control, without the addition of germ (CO−); CO plus xylanase (CO+); 200 g kg−1 inclusion of whole corn germ (WG−); WG plus xylanase (WG+); 200 g kg−1 inclusion of defatted corn germ (DG−); and DG plus xylanase (DG+). Experiment II - the palatability test was performed in pairs: CO vs. 200 g kg−1 WG, CO vs. 200 g kg−1 DG, and 200 g kg−1 WG vs. 200 g kg−1 DG. Xylanase addition, compared with enzyme-free, led to greater CTTAD of dry matter (0.807 × 0.787), crude protein (0.849 × 0.828), and gross energy (0.838 × 0.820) (P<0.05). An interaction showed that xylanase increased metabolizable energy in DG diet (P<0.05). Germ inclusion resulted in higher fecal dry matter compared with CO (407.4 × 377.3; P<0.05). The DG diet reduced propionic concentration and total short-chain fatty acids compared with WG and CO (P<0.05). There was a preference of WG over CO both in the first choice and intake (P<0.05). Xylanase supplementation improves nutrient digestibility and GE in dog fed diets containing whole or defatted corn germ, while not affecting fecal characteristics and intestinal fermentation products. The use of WG has a positive effect on diet palatability.

Abstract in English:

ABSTRACT This study aimed to compare hot blade with infrared beak trimming with different protocols on performance, beak length, digestive system organ biometry, intestinal histomorphometry, and egg quality in white laying hens. One hundred and twenty chicks were distributed in a completely randomized design in three beak trimming methods/protocols with five repetitions. Hot blade (HB) trimming was carried out at day 7, and infrared beak trimming was carried out at day 1, using light (LIR: 26/23 protection plate and 38 nm intensity) and moderate (MIR: 24/23 protection plate and 40 nm intensity) protocols. The birds were assessed up to 33 weeks. Up to 18 weeks, weight gain (WG), feed intake (FI), feed conversion (FC), breeding viability (BV), uniformity (UN), beak length (BL), digestive system biometry, and intestinal histomorphometry were evaluated. Between 18 and 33 weeks, age at sexual maturity, egg production, and quality were assessed. Hot blade trimming worsened initial performance with a reduction in FI, WG, and UN (P<0.05). On the other hand, lower BV was observed with the MIR beak treatment (P = 0.026). Beak length was shorter with the HB method (P<0.001). Hot blade trimming resulted in greater gizzard weight (P = 0.004) with no effect on intestinal histomorphometry (P>0.05). During the laying phase, there was no effect of beak trimming on age at sexual maturity, egg production, and egg quality (P>0.05), except eggshell thickness, which was lower with HB trimming (P = 0.025). Beak treatment using the light infrared radiation protocol could be a viable alternative to the hot blade.

Abstract in English:

ABSTRACT The objective of this study was to evaluate the hepatic metabolism and performance of broilers fed reduced-energy diets (50 kcal/kg less), with or without guanidinoacetic acid (GAA). A total of 432-day-old male chicks of the Cobb 500 lineage were distributed in a completely randomized design with three treatments and eight replications. The treatments consisted of a basal diet (BD), basal diet with a reduction of 50 kcal/kg (RBD) and a basal diet with a reduction of 50 kcal/kg supplemented with GAA (GAAD). The parameters evaluated were broiler performance, lipid metabolism, and hepatic histomorphometry. A multivariate analysis of lipid profile, hepatic histopathology, and energy intake was performed. At 21 and 28 days, birds fed BD and GAAD exhibited lower feed intake (FI) and birds fed BD showed the best feed conversion ratio (FCR) (P<0.05). At 41 days, the best FCR was observed in birds fed BD and GAAD (P<0.05). There was no difference in energetic intake of broilers at 41 days (P>0.05). However, birds fed BD had a higher FI (P<0.05). Birds fed GAAD showed a higher level of very low-density lipoprotein (VLDL) and triglycerides (TGL) and a lower level of albumin (ALB) (P<0.05). The hepatic histopathology showed a higher level of inflammation infiltrated in birds fed BD and GAAD (P<0.05). A multivariate analysis showed that birds fed GAAD had higher levels of high-density lipoprotein (HDL), VLDL, and TGL and a better liver interstitial pattern. The use of GAA improves the performance of birds fed GAAD compared with RBD and increases the availability of VLDL and TGL in the birds’ blood.

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ABSTRACT This study aimed to evaluate the effects of thermal processing and different carbohydrate sources on performance, development of digestive organs, and pancreatic enzyme activity in broiler chicks during the pre-starter phase. The experiment was conducted in a completely randomized design with a 2 × 2 factorial arrangement (pelleting or extrusion processing, and corn or sorghum) and included six replicates of 15 chicks each. The experimental diets were provided only during the pre-starter period (1–7 d). From 8 to 21 days of age, all chicks received a corn-soybean meat mash diet. At 7 days of age, chicks fed corn-based pelleted diets showed the best performance. When the feed was extruded, the best performance at 14 and 21 days old was observed with the sorghum-based diet. Chicks fed pelleted diets showed greater duodenum, jejunum, and ileum weights. Regarding carbohydrate sources, sorghum-fed chicks showed greater pancreas, jejunum, and ileum weights. Broiler chicks fed corn-based extruded diets exhibited higher pancreatic amylase activity. Extruded sorghum-based diets improved duodenum and jejunum villus development, whereas pelleted corn-based diets enhanced duodenal villus development. Although extruded sorghum diets did not affect digestive organ development, they improved duodenum and jejunum villus morphology, resulting in better performance up to 21 days of age. However, the corn-based extruded feed provided increased production of the pancreatic amylase enzyme. Sorghum-based feed, regardless of thermal processing, improved the development of digestive tract organs.

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ABSTRACT In this study, we investigated the effects of using poultry offal meal (POM) produced in rendering plants by adding dissolved air flotation sludge (DAFS) at set ratios into broiler grower and finisher feeds. The experiment conducted within the scope of the study lasted six weeks and involved 12,000 broiler chicks from Ross 308 strain middle-aged (36 weeks) breeders. Twelve different treatments were used in grower feed with 2 or 3% POM and finisher and pre-slaughter feeds with 4 or 5% POM produced by adding DAFS at 0, 11, and 22%, respectively. A downward trend was observed in average live weight (ALW), daily weight gain (DWG), feed conversion ratio (FCR), and European production efficiency factor (EPEF) values among the treatment groups, some of which were significant (P<0.05), as the usage rates of POM and DAFS increased. The treatment groups fed POM without DAFS in 2% grower and 5% finisher feeds had significantly higher ALW and EPEF values and significantly lower FCR values than the group fed POM at 22.0% in 3% grower and 5% finisher feeds (P<0.05). However, the mortality value remained unchanged according to the POM and DAFS usage rates (P>0.05). As a result, POM may be used in broiler feeds without significantly affecting ALW, DWG, FC, FCR, EPEF, and mortality values. However, if DAFS is used in POM production, attention should be paid to DAFS content, since exceeding certain levels may cause a downgrade in ALW, FCR, and EPEF values.

Abstract in English:

ABSTRACT This study aimed to evaluate the development of the gastrointestinal tract and organs in 18-days embryos (ED18) and newly hatched chicks from broiler breeders supplemented with conjugated linoleic acid (CLA), as well as the development of their progeny up to 7 days of age, which also received CLA supplementation in the pre-placement diet during the first 12 hours post-hatch. A total of 540 eggs from two Cobb500 breeder flocks, supplemented with either 0 or 0.025% CLA, were incubated, and after hatching, broiler chicks received diets containing either 0 or 0.025% CLA for 12 hours before placement. A total of 320 chicks were housed in a completely randomized 2 × 2 factorial design (breerder CLA × post-hatch CLA), resulting in four treatments with eight replicates of 10 birds each. Intestinal development and relative organ weight (RW) were assessed at 18 days of incubation, at hatching, at 12 hours of holding, and at 7 days post-hatch; performance from 1 to 7 days was also evaluated. Supplementation of CLA (both broiler breeders and pre-placement diet) increased body weight (BW) at 12 h of holding and reduced pancreas RW at 7 days (P<0.05). The RW of the stomach and liver were higher at 7 days when only one source of supplementation was provided (P<0.05). Post-hatch CLA supplementation increased the lengths of the total and small intestines, while breeder supplementation alone also increased small intestine length (P<0.05). Both total and small intestine RW were lowest in the absence of CLA supplementation (P<0.05). Breeder supplementation with CLA led to improved BW and weight gain by day 7. The data shows that CLA supplementation in broiler breeders and their progeny affects gastrointestinal tract and organ development, and supplementation of breeders is recommended to enhance early performance.

Abstract in English:

ABSTRACT The objective of this study was to investigate the effects of supplementation with the ethanolic extract of Myrciaria cauliflora peels and seeds on the performance and intestinal health of broilers inoculated with Salmonella Heidelberg and reared until 28 days old. Three hundred thirty-six one-day-old male broiler chickens were distributed in a completely randomized design with four treatments and seven replications each: NC - negative control, which received a 0.85% sterilized saline solution in the crop; EJ - group that received the plant extract in the feed; SH - group that received the bacterial inoculum in the crop; and SH + EJ - group that received the bacterial inoculum in the crop and was fed the herbal extract in the diet. Supplementation with the herbal extract did not influence performance and increased Salmonella excretion in inoculated broiler chickens at 11 and 28 days old. Salmonella reduced jejunal villi height at 28 days, suggesting that the herbal extract caused a dysbiosis that favored the colonization and multiplication of Salmonella. The increased pathogen excretion may rise the transmission rate and the risk of foodborne illness. The use of the ethanolic extract of jabuticaba does not affect weight gain, feed conversion, average weight, histomorphometry, or intestinal biometry, but it increases Salmonella Heidelberg excretion.

Abstract in English:

ABSTRACT This study examined the effect of colostrum intake on pre-weaning mortality in piglets, focusing on neonatal vitality traits. Data from 2,050 piglets and 136 sows were collected from a commercial farm. Sows were monitored during gestation (parity, body condition, backfat thickness, weight gain, and gestation duration) and farrowing was monitored (duration, live births, mummified fetuses, stillbirths, maternal glucose, birth intervals, birth order, and sex). Neonatal traits (colostrum intake, meconium presence, umbilical rupture, rectal temperature, glucose, oxygenation, and heart rate) and performance measures (birth weight, weaning weight, and mortality) were recorded. Piglets that did not survive until weaning were born to sows with a longer farrowing duration (+26%; P<0.001), higher birth orders (+14%; P = 0.047), lower birth weights (−21%; P<0.001), reduced oxygenation (−1%; P = 0.019), lower rectal temperatures (−4%; P = 0.033), and significantly lower colostrum intake (−38%; P<0.001). Mortality was associated with rectal temperatures (<38.35 °C), colostrum intake (<172 g), birth weights (<897.5 g), and farrowing durations (>301 min), as identified by a tree-based model. Low colostrum intake correlated with longer farrowing durations (+7%; P = 0.044), longer birth intervals (+32%; P = 0.013), higher birth orders (+12%; P = 0.015), lower body weights (−5%; P = 0.005), reduced umbilical rupture rates (−11%; P = 0.049), lower rectal temperatures (−1%; P = 0.046), and lighter weaning weights (−10%; P<0.001). The model suggested that low colostrum intake was linked to birth weight (<990 g), sow body condition during gestation, and farrowing durations (>343 min). These results underscore the complex factors influencing colostrum intake and mortality, critical for sustainable swine production.

Abstract in English:

ABSTRACT The objective of this study was to characterize the sexual development of 48 Nelore bulls by associating the findings of sperm analyses with growth traits and ultrasound-measured testicular traits. Bulls were evaluated from 14.3 to 24.6 months old at intervals of 28 days, totaling 12 observations per animal. Data were subjected to repeated-measures analyses of variance over time (PROC MIXED, SAS 9.2) and equations for semen traits were developed using stepwise regression (PROC REG, SAS 9.2). Regarding the growth performance on pasture, there was an increase in average body weight (388 to 500±4.59 kg), body condition (5-6), and hip height (139 to 145±0.52 cm) with increasing age. However, a lower average daily gain (0.64 to 0.29±0.05 kg) was observed during the dry season. Reproductive traits such as scrotal circumference (27 to 33.6±0.34 cm), testicular artery diameter (2.14 to 2.96±0.04 mm), blood testosterone concentration (8.3 to 22.7±1.48 mg/mL), sperm motility (total: 42 to 82.8±2.91% and progressive: 26.2 to 62.3±2.61%), percentage of rapid cells (38.1 to 79.8±2.9%), and sperm concentration (43.6 to 645±42.1 × 106/mL) increased with increasing age, while there was a reduction in sperm defects (major: 59.4 to 9.6±3.18% and total: 62.5 to 15.1±2.94%). Ultrasonography and growth traits have a moderate power to predict major and total sperm defects but cannot predict other seminal traits. By 19-20 months of age, Nelore bulls start to exhibit reproductive traits that indicate the attainment of sexual maturity.

Abstract in English:

ABSTRACT This study investigates whether pre-pubertal scrotal circumference (SC) and anti-Müllerian hormone (AMH) concentrations indicate sexual precocity in Brahman and Simmental bulls. Fifty-three bulls (Brahman, n = 27; Simmental, n = 26) were used. Scrotal circumference was measured at three periods: pre-puberty (Brahman = 19.99±0.20 months; Simmental = 9.13±0.17 months), puberty (Brahman = 21.42±0.20 months; Simmental = 18.26±0.17 months), and post-puberty (Brahman = 33.34±0.55 months; Simmental = 24.07±0.17 months). A single sample taken at the pre-pubertal period was used for the AMH determination. Two classes were defined based on the frequency distribution of AMH concentrations: low AMH <2.28 ng/mL and high AMH ≥2.28 ng/mL. Scrotal circumference was negatively correlated with the percentage of total defects (r = −0.5957; P = 0.0246) and positively correlated with the percentage of normal sperm (r = 0.595; P = 0.0265). There was a high correlation between SC and assessment periods (pre-puberty, puberty, and sexual maturity) in both breeds (Brahman: r = 0.8776; P = 0.0005; Simmental: r = 0.7483; P = 0.0002). At puberty, SC was higher (P = 0.0002) in animals of the low AMH class (34.78±0.78 cm) than in the high AMH class (32.47±0.42 cm). Males classified as having low AMH concentration had better (P<0.0001) andrological assessments, (vigorous oscillatory movement or vigor: 3.92±0.20; sperm mass movement or turbulence: 2.63±0.19; progressive motility: 77.55±3.80) than those classified as having high AMH concentration (vigor = 3.33±0.19; turbulence = 2.06±0.19; progressive motility = 65.14±3.79). Pre-pubertal AMH concentrations are negatively correlated with SC and are a good predictor of sexual precocity in Brahman and Simmental bulls.

Abstract in English:

ABSTRACT The objective of this study was to compare reproductive performance and progesterone (P4) concentration in serum of synchronized ewes with new and reused (up to five times) CIDR in five-day protocols. Two experiments were conducted in the reproductive season, in two consecutive years. In experiment 1: 125 µg of PGF2α and 200 IU of eCG were applied at removal of the CIDR: CIDR1-200 (new intravaginal devices, control), CIDR2-200, CIDR3-200, CIDR4-200, and CIDR5-200 (groups with CIDR from second to fifth use, respectively). In experiment 2, ewes received the same protocol with a dose of 400 IU eCG: CIDR1-400 (control), CIDR2-400, CIDR3-400, CIDR4-400, and CIDR5-400 (groups with CIDR from second to fifth use, respectively). In the first experiment, estrus rate was 92% in the first and second uses, 100% in the third and fourth uses, and 95% in the fifth use. Pregnancy rates were 85% in first and second uses and 81, 73, and 57% from third to fifth CIDR uses, respectively. In the second experiment, estrus rate was 100, 96, 92, 96, and 95% from the first to fifth uses, respectively. Pregnancy rates were 85, 88, 85, 77, and 62% from the first to fifth uses, respectively. Estrus and pregnancy rates did not differ statistically. Estrus was concentrated between 24 to 48 h in experiment 1 and between 24 to 36 h in experiment 2. Prolificacy index was 1.3 and 1.6 in the first and second experiments, respectively. Progesterone concentration was >2 ng/mL after the insertion of CIDR in all groups. The CIDR (plus PGF2α and eCG) can be used up to four times for estrus synchronization in five-day protocols without affecting reproductive performance.

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ABSTRACT The effect of a dose of GnRH administration at sponge insertion on pregnancy rate and litter size in ewes was investigated. A total of 162 pluriparous, non-lactating Huyang ewes (3–4 years old, 40–50 kg body weight, 120–150 days postpartum) were randomly and equally assigned to three groups (n = 54 each): control, G25, and G50. Estrus was synchronized using an intravaginal sponge impregnated with flurogestone acetate for 12 days, followed by an injection of 330 IU of equine chorionic gonadotropin at sponge removal. At sponge insertion, ewes received an intramuscular injection of either 25 µg (G25) or 50 µg (G50) of the GnRH agonist triptorelin, or saline solution (control). Fixed-time artificial insemination was performed at 52 and 60 h after sponge removal. Pregnancy was diagnosed by transabdominal ultrasonography 45 days post-insemination, and reproductive parameters were recorded after lambing. Pregnancy rate was not affected by GnRH administration (P = 0.3001). However, the multiple birth rate (P = 0.0032) and litter size (P = 0.0012) were significantly increased in the G50 group compared with control. In conclusion, administration of 50 µg of GnRH at sponge insertion increased litter size in Huyang ewes subjected to fixed-time artificial insemination.

Abstract in English:

ABSTRACT The objective was to evaluate the effect of delivery frequency of loose mineral mixtures (LMM) offered to grazing steers on the physicochemical characteristics of the mixture and animal performance. Two experiments were carried out both during the wet-to-dry transition period (March 2021 to June 2021) and during the rainy season (November 2021 to March 2022). Brangus steers (n = 120, distributed in 24 paddocks) were used in experiment 1 and Nellore steers (n = 96, distributed in 20 paddocks) in experiment 2. The LMM contained 8% phosphorus and was delivered at two different frequencies: weekly (DF7d) and every 21 days (DF21d). The paddock was considered the experimental unit, with 12 experimental units in experiment 1 and 10 experimental units in experiment 2. The LMM disappearance was assessed as the difference between LMM delivered mass and orts. Assessments included the chemical characteristics of the LMM orts, the rainfall drained water mineral content and its electrical conductivity, fecal and plasma mineral content, and animal performance. Data were analyzed for outliers and subjected to analyses of maximum restricted likelihood. In experiment 1, drained rainfall water was higher for DF21d. There were differences in plasma and fecal mineral concentrations due to homeostatic balance. There were no significant differences in average daily weight gain (ADG) between treatments during the wet-to-dry transition period (P>0.05); however, the ADG of animals supplemented weekly was 60 g higher than ADG of animals in the DF21d treatment (P<0.04). During the rainy season, there was a greater demand for force to penetrate the mass of the mixture for the DF21d treatment (2.14 vs. 1.63 kg/cm2; P = 0.01). The delivery frequency of loose mineral mixtures changes the physicochemical patterns of the supplement, affecting animal performance, which is more evident during the rainy season.

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ABSTRACT This study was conducted to determine the effects of adding pomegranate peel and oregano pulp at different levels (2, 4, 6, and 8%) on a dry matter basis to sheep rations on methane production and rumen fermentation using the in vitro gas production technique. In the study, nine experimental groups were formed by adding different levels (2, 4, 6, and 8%) of pomegranate peel and oregano pulp to the total ration mixture (control ration). Each treatment group was designed with four replications. Rumen fluid was taken from two sheep that were fed mainly roughage. For each feed treatment, four gas production syringes were used. A trial design was created using a total of 40 gas production syringes, and four gas production syringes for blank samples. The prepared syringes were incubated for 24 h. The additive levels of pomegranate peel and oregano pulp did not change total gas, methane (%), and methane (mL) production compared with the control treatment. The use of pomegranate peel and oregano pulp for in vitro rations significantly reduced rumen fluid volatile fatty acid (VFA) levels, except for 2% pomegranate peel. In vitro organic matter digestibility and metabolizable energy levels of both additives were similar to the control ration. In the study, the addition of pomegranate peel and oregano pulp to total ration mixture at 2, 4, 6, and 8% levels did not change total gas and methane production. Except for the addition of 2% pomegranate peel, the treatments suppressed rumen fluid VFA. Besides, it is thought that the additives used in the study can be used up to 2% in the rations of ruminant animals in regions where they may create waste to reduce feed costs.

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ABSTRACT This study aimed to evaluate the effects of dried or rehydrated corn and sorghum grains on nutrient intake, performance, and economic analysis in high-grain diets (30:70) of Nellore bulls finished in a feedlot system. The experiment was completely randomized and replicated four times (two animals/pen), in which 32 Nellore bulls with an initial body weight (IBW) of 324.8±4.42 kg were fed in 16 pens according to the following treatments: rehydrated corn silage (RCS), rehydrated sorghum silage, dry corn grain, and dry sorghum grain. Dry matter intake, IBW, and final body weight did not differ among treatments, although diets with RCS and ground corn grain had better daily weight gain (1.60 and 1.52 kg/head/day, respectively). Rehydrated corn silage allowed lower daily costs (US$ 2.12/day) in relation to ground corn grain (US$ 2.14/day). Rehydrated sorghum grain silage is recommended instead of dry sorghum grain in beef cattle diets since it provides greater net margin, without affecting the average daily gain. Similarly, the rehydrated corn grain diet presents greater technical and economic efficiency than dry sorghum or rehydrated sorghum silage, indicating greater system profitability.

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ABSTRACT Mathematical modeling is a systematic process that involves identifying key variables and understanding how they interact. This review provides a comprehensive pedagogical framework for new researchers in animal science modeling, addressing the critical gap between general modeling theory and domain-specific applications. While modeling typically begins with conceptualization using visual aids such as causal loop diagrams, stock and flow diagrams, mind maps, and flowcharts to organize relationships among variables, there is a notable lack of resources that effectively bridge theoretical concepts with practical applications in animal science. This process allows scientists to build simplified representations of complex systems while providing structured guidance specifically tailored to biological systems. Modelers must balance simplicity and complexity to maintain functionality while reflecting real-world systems. Simple models, though limited, offer greater usability and interpretability, while complex models can become challenging to apply practically. After translation to mathematical form and computer code, models undergo rigorous parameterization with real-world data, evaluation against independent datasets, and sensitivity analyses. Models challenge our understanding, reveal knowledge gaps, and guide research. By embracing an iterative approach to model development—in which refinement and improvement are continuous—researchers can develop models that are not only accurate and predictive, but also practical and usable in addressing real-world challenges. This continuous development cycle, evaluation, and application ensures that models remain relevant and capable of evolving alongside scientific knowledge and technology advancements.

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ABSTRACT This study aimed to establish the optimal concentration of purified Kraft lignin (PKL) in the diet of finishing lambs. The experiment was arranged in a randomized block design, with four diets and LKR concentrations of 0, 6, 12, and 18 g/kg DM, with eight Poll Dorset × Texel crossbred lambs per treatment. The experiment was conducted with newly weaned lambs, aged 60 ± 10 days, with an average initial body weight of 23 ± 5 kg. The animals were housed in individual stalls for 69 days. Their performance was measured during the experiment, and the carcass, meat quality, and viscera were evaluated after slaughter. An orthogonal polynomial regression study was performed with a 5% significance level. Including PKL did not alter the performance parameters body weight, average daily weight gain, feed efficiency, and dry matter intake. The inclusion of lignin increased the amount of superoxide dismutase and glutathione peroxidase in the blood (P<0.05). In addition, there were no changes in carcass quality parameters hot and cold carcass weight, hot and cold carcass yield, rib eye area, pH, and temperature. The L* content was lower in the treatment with 18 g of lignin (P = 0.0135). Fecal microbiology had a cubic effect (P = 0.0509) with lower values (154.81 CFU/mL) at 18 g/kg DM. The treatment with 12 g of lignin had zero rumenitis index, and the highest occurrence was with 6 g (P<0.0001). There was no difference among treatments for commercial meat cuts and viscera. At the concentrations used, PKL does not alter performance characteristics, carcass and meat quality parameters, but it has an antimicrobial and antioxidant effect.

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ABSTRACT Two studies were carried out to investigate the effects of crude glycerin (CG) levels in feedlot sheep diets as a substitute for ground corn. In the first study, four castrated rumen-canulated sheep were used to assess the effects of CG on nutrient intake, digestibility, rumen characteristics, and blood glucose. In the second study, 40 crossbred female lambs were employed to evaluate the influence of CG levels in the diet on nutrient intake, digestibility, and animal performance. Crude glycerin levels did not affect nutrient intake in either study, except for crude fat (CF) intake, which increased linearly as neutral detergent fiber decreased. However, the digestibility of dry matter, CF, total carbohydrates, and non-fibrous carbohydrates increased linearly, with CF being quadratically affected in both studies. Rumen pH (mean = 6.1) and blood glucose (mean = 61.72 mg/dL) remained unaffected by CG levels, whereas ruminal ammonia nitrogen displayed a quadratic response. Additionally, CG levels did not impact the performance (mean = 204.6 g/d) in female feedlot lambs, suggesting that CG can be included in sheep diets at up to 30% in a mixed forage diet.

Abstract in English:

ABSTRACT The objective of this study was to evaluate the effect of castration and days of feed (DOF) on glucose sensitivity and muscle expression of genes related to glucose metabolism, muscle growth, and fat deposition. Thirty-six Nellore bull calves were either surgically castrated or left intact, then harvested at 0, 100, or 200 DOF. Glucose tolerance tests were performed at 100 and 200 DOF. Longissimus dorsi (LD) samples were taken just after stunning for gene expression. Data were analyzed as a complete randomized design following a two (sexual condition) × three (DOF) factorial arrangement of treatments. An interaction effect was found for carcass fat gain (P = 0.01), showing that steers gained more fat than bulls from 100 to 200 DOF, but both sexual classes had a similar fat gain from 0 to 100 DOF. Basal blood glucose and the area under the curve post-infusion were not affected by castration or DOF (P>0.05). Castration tended (P = 0.08) to upregulate LD expression of Acetyl-CoA carboxylase alpha (ACACA). Interaction effects (P<0.05) were found for LD expression of IGF-1 receptor (IGF1R) and F-box protein 32 (FBXO32) with steers having greater relative abundance for both genes at 100 DOF, while bulls had greater relative abundance at 200 DOF. Despite the greater carcass fattening enhancement by castration and longer DOF, whole-body sensitivity to glucose does not change.

Abstract in English:

ABSTRACT Two experiments were carried out aiming to evaluate the effect of copaiba oil on growth performance, apparent digestibility of nutrients, and rumen fermentation in lambs on feedlot. The treatments were: no additive inclusion (negative control); 8 mg/kg of sodium monensin (MS; positive control); and 250, 500, and 750 mg of copaiba oil/kg dry matter added to a diet with 70% concentrate and 30% forage. In experiment I, five lambs (Dorper × Santa Inês) cannulated in the rumen, 8 ± 1.0 months old and 51.4 ± 0.7 kg of initial body weight (BW) (mean ± SD), were assigned in a 5 × 5 Latin square design to assess ruminal parameters, apparent digestibility of nutrients, and nitrogen balance. In experiment II, 40 lambs (Dorper × Santa Inês), 8 ± 1.0 months old and 37.7 ± 1.6 kg of initial BW, were registered. The experimental design was in completely randomized blocks (five treatments and eight blocks). The treatments were: no additive inclusion (negative control); 8 mg/kg of sodium monensin (MS; positive control); and 250, 500, and 750 mg of copaiba oil/kg dry matter added to a diet with 70% concentrate and 30% forage. The experimental trial lasted 84 days, divided into three sub-periods of 28 days. Additives did not affect growth performance. Total dry matter intake, individual nutrient intakes, and apparent digestibility were not influenced by feed additives. The additives also did not affect the short-chain fatty acids molar concentration, ruminal pH, and ruminal ammonia nitrogen. Feed additives, in the dosages of 250, 500, and 750 mg of copaiba oil/kg of DM used in this experiment, are not effective to modify growth performance, apparent digestibility, and ruminal fermentation in lambs.

Abstract in English:

ABSTRACT This study aimed to evaluate the effects of total replacement of soybean meal and partial replacement of ground corn with licuri cake (LC) in the diet of young Nellore bulls on feed intake, ingestive behavior, nutrient digestibility, nitrogen balance, microbial protein synthesis, animal performance, carcass traits and economic efficiency, including marginal costs and returns. Thirty-two 16-month-old Nellore bulls (346 ± 32.5 kg body weight) were individually evaluated in a completely randomized experimental design with four treatments (0, 7, 14, and 21% dry matter [DM]) and eight replications. The animals were feedlot-finished for 84 days, fed a diet consisting of 60% Tifton-85 hay as roughage and 40% concentrate mixture. The concentrate included ground corn, soybean meal, urea, ammonium sulfate, and mineral mixture. The inclusion of LC in the bulls’ diets linearly reduced (P<0.05) the intake of DM, crude protein (CP), neutral detergent fiber (NDF), total digestible nutrients (TDN), and nitrogen, as well as fecal N, urinary N excretion, and N retention. On the other hand, LC inclusion quadratically increased (P<0.05) ether extract (EE) intake and microbial protein synthesis. In addition, there was a linear increase (P<0.05) in the digestibility of CP, EE, and NDF, as well as in the percentage of bone, muscle, and muscle tissue:fat tissue ratio in the young bulls. In contrast, animal performance, hot and cold carcass weights, fat tissue content, diet cost, and financial returns linearly decreased (P<0.05). Based on the levels tested, the inclusion of LC in bulls’ diets is not recommended, as it reduces feed intake, performance, and overall financial profitability of the activity.

Abstract in English:

ABSTRACT This study aimed to evaluate the effects of backgrounding supplementation, by increasing the levels of energy-protein supplements during the growing phase on the performance and rumen morphometrics of Nellore bulls intensively finished on pasture. Ninety-six Nellore bulls were blocked according to initial body weight (BW) of 385.6 ± 7.3 kg and randomly assigned to one of 24 paddocks of Urochloa brizantha cv. 'Piata' (four animals/paddock). The animals were supplemented during the growing phase as follows: (1) energy-protein supplementation at 0.05% BW, (2) energy-protein supplement at 0.1% of BW, (3) energy-protein supplement at 0.3% BW, and (4) energy-protein supplement at 0.5% of BW for 112 days. Thereafter, all bulls were fed a concentrate at 1.5% BW for 84 days in the finishing phase on pasture. The supplement intake, BW assessment, and average daily gain (ADG) were recorded every 28 days. At the end of the trial, the hot carcass weight was recorded. Rumen and cecum were scored, and morphometric parameters evaluated. Dry matter intake during both the growing and finishing phases increased with higher levels of supplementation (P<0.01). There was a quadratic effect (P = 0.03) during the growing phase, with bulls supplemented at 0.3% and 0.5% of BW showing greater ADG; however, during the finishing phase, a linear decrease effect was observed (P = 0.01). A linear increase effect was observed for final BW, with bulls consuming 0.05% of BW being lighter. In addition, as the level of supplementation increased, hot carcass weight also increased (P<0.01), while no effects were observed on rumen and cecum parameters. Providing an energy-protein supplement during the growing phase is an effective nutritional strategy. Higher levels of supplementation result in greater final body weight at the end of the growing phase and, consequently, improved performance during the finishing phase of Nellore bulls finished on pasture.

Abstract in English:

ABSTRACT This study aimed to assess the ruminal fermentation of various cottonseed (Exp. 1) and peanut (Exp. 2) meals, each processed using different techniques and exhibiting varying levels of rumen undegradable protein (RUP). Six treatments were evaluated for each feed. For Exp. 1 (cottonseed meal): negative control (conventional meal; Ncontrol), microwave-heated (2 min) with 2% xylose, conventional oven-heated (90 min) with 2% xylose, autoclave-heated (8 min) with 2% xylose, tannin treatment (6% inclusion), and a commercial soybean-based product (Pcontrol). For Exp. 2 (peanut meal): negative control (conventional meal; Ncontrol), microwave-heated (6 min) with 2% xylose, conventional oven-heated (60 min) with 2% xylose, autoclave-heated (24 min) with 2% xylose, tannin treatment (6% inclusion), and a commercial soybean-based product (Pcontrol). An in vitro gas production (GP) system was used to evaluate gas production, kinetics, and fermentation patterns, while the in vitro organic matter digestibility (IVOMD) was assessed using an in vitro incubator system. Both experiments consisted of three consecutive 48-hour fermentation batches. The conventional oven exhibited the lowest fermentation rate and the largest gas pool size (P<0.01) in both experiments. Tannin resulted in the lowest total GP at both 24 and 48 hours, IVOMD, and metabolizable energy for both meals (P<0.01). Tannin also reduced branched-chain volatile fatty acid in Exp. 1 (P<0.01). The Ncontrol and Pcontrol treatments showed the highest estimated methane concentration in Exp. 2 (P<0.01). These findings indicate that both conventional oven heating and tannin effectively alter the ruminal fermentation of cottonseed and peanut meals, highlighting their potential as alternative sources of RUP in beef cattle nutrition.

Abstract in English:

ABSTRACT This study aimed to assess the productive performance and carcass characteristics of feedlot lambs fed corn grain silage rehydrated with different solutions. Twenty-eight Santa Inês ram lambs, approximately 75 days of age and with an average weight of 17.05±3.75 kg, were randomly assigned to one of four dietary treatments: dried corn grains (control); whey-rehydrated corn grain silage; water-rehydrated corn grain silage; and water + additive-rehydrated corn grain silage. For animal performance, dry matter intake, average daily weight gain, and feed conversion were evaluated. After 76 days on feedlot, with an average body weight of 31.76±3.44 kg, animals were slaughtered and carcass yield and morphometric measurements were measured. Particle size selection was evaluated by the Penn State Particle Separator for the refusals. Silage samples were also analyzed for pH, buffer capacity, and ammonia nitrogen content. Performance results were not affected by dietary treatments. On the other hand, differences were observed for dry matter intake per unit of metabolic weight, in which whey-rehydrated corn grain silage (69.58 kg/LW0.75) and dried corn grains (76.21 kg/LW0.75) exhibited the lowest intakes. The overall mean for dry matter intake was 0.949 kg/day. Since there were no differences in the results for performance and carcass characteristics of the animals among the experimental diets, the use of rehydrated silage is not recommended, as it could increase production costs when compared with dry corn grain. Regarding the lower feed intake observed when rehydrated corn grain silage with whey was used, further studies need to be carried out.

Abstract in English:

ABSTRACT The objective of this study was to evaluate in vitro effects on ruminal fermentation of by-product from the production of edible mushroom Pleurotus ostreatus. The following by-products were tested: (I) non-colonized sugarcane bagasse (control); (II) sugarcane bagasse from non-enriched mushrooms; and (III) sugarcane bagasse from selenium-enriched mushrooms. A semi-automatic in vitro system was used. The pH and neutral detergent fiber (NDF) residue were determined at 0, 3, 6, 9, 12, 18, 24, 48, 72, and 96 h of incubation. The ruminal ammonia nitrogen (NH3-N) concentrations were measured at 0, 6, 12, 24 and 48 h incubation times and the short-chain fatty acids (SCFA) concentrations after 24 h incubation. The pH and NH3-N were not affected (P>0.05) by the treatments or the treatment × time interaction. However, an effect of incubation time was observed (P<0.05). The production of SCFA was not affected (P>0.05). Non-colonized sugarcane bagasse presented a higher value of the potentially degradable fraction (P<0.05) and a lower value of the undegradable fraction when compared to the other treatments (P<0.05). The results indicate that the by-products do not change the fermentative parameters.