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ABSTRACT The aim of this study is to investigate the morphological characteristics of blood cells and spermatozoa of Chinese monals (Lophophorus lhuysii) and to provide a basis for artificial insemination and physiological research. In this study, blood samples were collected by the wing vein puncture method, and semen was obtained by the massage technique. Blood cells were stained using Wright-Giemsa stain, while sperm were stained with Wright-Giemsa and modified Papanicolaou stain. The morphological and ultrastructural features of blood cells and sperm were observed using optical microscopy and scanning electron microscopy. The results indicate that mature red blood cells of the Chinese monal are oval with a smooth surface, measuring 12.43±0.89μm in major axis length. Immature red blood cells are larger and spherical, with a major axis length of 10.79±0.91μm. Sperm are elongated and rod-shaped, featuring a flagellum, with an average total length of 63.28±1.74μm, including a head length of 16.98±0.41μm and a tail length of 46.30±1.74μm. Scanning electron microscopy reveals a rough sperm surface with clear distinctions between the acrosome, head, and flagellum. Optical microscopy also shows a certain proportion of abnormal spermatozoa. This study elucidates the size and structural characteristics of blood cells and sperm in the Chinese Monal, providing a foundational basis for research in hematophysiology, fertilization, and population breeding, and offers technical support for the construction of genetic resource banks and the expansion of artificial populations.

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ABSTRACT Antimicrobial resistance (AMR) is a pressing global public health issue, driven by the widespread use of antibiotics in both human and veterinary medicine. Tetracyclines, widely used in livestock for growth promotion and disease treatment, have contributed significantly to the emergence of resistant bacterial strains. This study aimed to evaluate the tetracycline resistance profiles of Salmonella spp. and Escherichia coli isolates from the poultry supply chain in Brazil, and identify the primary tetracycline resistance genes involved. A total of 97 Salmonella strains and 195 E. coli strains were analyzed for tetracycline resistance using the disc diffusion method and PCR to detect resistance genes (tetA, tetB, tetC, tetD, tetE, and tetG). The results revealed high tetracycline resistance rates, with 88.66% of Salmonella strains carrying the tetA gene, 4.12% harboring tetB and 1.03% carrying tetD. Among E. coli isolates, 64.62% carried tetA, 65.13% carried tetB, and 43.59% exhibited both genes. The tetE gene was detected in 1.03% of E. coli strains. These findings highlight the widespread presence of tetracycline resistance determinants in poultry-associated bacteria, underscoring the need for stricter antimicrobial use regulations and enhanced AMR monitoring in animal production systems to mitigate public health risks.

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ABSTRACT This research aimed to design, fabricate, and test a prototype of a 1-feed-line automatic chicken feeder, determining the designed functionality and feeding time, and comparing the performance of an automatic feeding system applied to a closed-system broiler chicken farm (Jariya Farm, Nakhon Ratchasima, Thailand) with the traditional feeding method. On-site tests were conducted using both traditional and automatic methods, with 19,200 chickens subjected to each method. After installing the automatic feeder, the results showed that the total number of chicken deaths decreased from 599 to 490 (18% reduction) and the survival rate increased from 96.9% to 97.5%. Moreover, the feed conversion ratio (FCR) improved from 2.6 to 1.7. Test results indicate that the automatic chicken feeder is highly beneficial for managing feed distribution on the farm. Each pan was always full of food, and broiler chickens could eat at all times, avoiding the competition for food that occurs in the traditional system. This reduced congestion and the risk of chickens stepping on each other while feeding, leading to lower death levels, a noticeably higher survival rate, and an improved FCR. Hence, the system offers an effective method for broiler feeding and an opportunity for large-scale industrial applications. The installation of this system allows farmers to break even in less than two months.

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ABSTRACT Despite the substantial increase in egg production and consumption in Türkiye in recent years, price fluctuations remain prevalent. Forecasting consumer prices for eggs is, therefore, a complex endeavor. This study analyzed various factors affecting egg prices, including layer hen feed price, corn and sunflower meal costs, wheat prices, distillers dried grains with solubles (DDGS) prices, the dollar exchange rate, the producer price index (PPI), and agricultural PPI data spanning January 2010 - April 2022. The dataset comprised 148 monthly data points influencing unitary egg prices. Random forest regression analysis was employed to investigate the determinants of consumer egg prices in Türkiye. Results indicated that economic indicators such as the exchange rate, feed price, and producer price index significantly impact egg prices. The random forest regression model exhibited high explanatory power (R2=% 95.2) in predicting egg prices. This study enhances understanding of factors influencing consumer price fluctuations in the egg poultry sector, enabling stakeholders to make more informed and strategic decisions concerning egg prices.

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ABSTRACT This meta-analysis evaluated the effect of emulsifiers or lipase as lipid digestibility enhancers on the yield of breast, thigh, and abdominal fat of broilers during the complete production cycle. Primary studies were obtained from the PubMed, Scielo, Science Direct, Scopus, and Web of Science databases, resulting in a total of 2,669. Of these, 18 were selected for meta-analysis, with information from 9,387 chickens. The average difference between breast, drumstick, and abdominal fat yield of chickens that were supplemented or unsupplemented with emulsifier and/or lipase was adopted as the effect size measure in the meta-analysis. Different weights were attributed to the studies by the inverse variance method. The significance of the general average difference was obtained through the Z test. The heterogeneity among studies was verified by the chi-square test and its magnitude was estimated by the index of inconsistency, with the adoption of a model of random effects. Subgroup analyses were performed to evaluate the level of interference of sex, lipidic source and concentration (%), type of additive and concentration (%), metabolizable energy of the feed (kcal/kg), and poultry lineage on final results. Results show there is evidence that emulsifier or lipase supplementation improves breast yield, though it does not improve drumstick yield or deposition of abdominal fat in broiler chickens during the complete cycle period. Further studies are required regarding this issue to quantify the impact of these additives on the observed results.

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ABSTRACT There is increasing interest among nutritionists in formulating reduced crude protein (CP) diets for poultry. Nearly a century of research has offered biochemical insights into the effects of reduced CP diets in broilers but practical implementation of such diets for laying hens remains limited. Therefore, this study aims to investigate the effect of varying crude protein (CP) and amino acids (AA) levels on growth performance, gas emission, organ weight, and body condition score in laying chicks. n=480, 1d old chicks were allocated into six treatment groups with 5 replicates of 16 birds/pen. The dietary treatments for Phase 1 (0-6 weeks) were as follows: CON - 18.5% CP with 100% digestible AA; TRT1 - 18.5% CP with 100% digestible AA; TRT2 - 18.5% CP with 105% digestible AA; TRT3 - 18.0% CP with 100% digestible AA; TRT4 - 18.0% CP with 100% digestible AA; and TRT5 - 18.0% CP with 105% digestible AA. In Phase 2 (6-16 weeks), the CP level was reduced by 2% in the CON, TRT4, and TRT5 diets, and by 2.5% in TRT1, TRT2, and TRT3 diets, while the AA levels remained consistent in all treatments. Our study demonstrates that slight variations in protein levels and AA have no impact on growth performance, gas emission, organ weight, and body condition score in laying chicks. In summary, we infer that poultry diet can be flexible and potentially reduce protein levels if ensuring sufficient AA, thus optimizing performance without negatively affecting the growth.

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ABSTRACT This study aimed to determine the growth and quality of broiler meat under different treatments. The experiment consisted of four distinct groups: viz. control (UBCONG), biofield energy treatment on eggs (BTEG), biofield energy treatment on chicks (BTCG), and biofield energy treatment on eggs and chicks (DBECG). Body weight, feed conversion ratio (FCR), carcass characteristics, and sensory features score (9-point hedonic scale) were evaluated. FCR was significantly (p<0.001) reduced in biofield treatment groups compared to UBCONG. Edible meat weight was significantly higher in BTCG (p<0.01; 55.23%), and DBECG (p<0.05; 47.67%) compared to UBCONG. Monounsaturated fatty acid (MUFA) was significantly increased by 111.11% in BTCG and 118.52% (p<0.05) in DBECG compared to UBCONG. Polyunsaturated fatty acid (PUFA) was significantly increased by 108.70% (p<0.01) in BTCG and 130.43% (p<0.001) in DBECG compared to UBCONG. Oleic acid was significantly (p<0.05) increased by 172.22% in BTCG and 150% in DBECG compared to UBCONG. Linoleic acid was significantly (p<0.001) increased in BTCG (146.67%) and DBECG (160%) compared to UBCONG. Sensory characteristics were significantly (p<0.001) improved in the biofield treatment group as compared to UBCONG. Overall, the biofield treatment significantly improved growth and quality of broiler chicken meat compared to the untreated group.

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ABSTRACT This study investigated the effects of antimicrobial peptide Q4-15-2A7P on the growth performance and gut health of broilers under Clostridium perfringens toxin challenge. A total of 144 one-day-old broiler chicks (Ross 308) were assigned to four groups: negative control (NC), positive control (PC; phospholipase C [PLC, C. perfringens toxin] challenge), prevention peptide group (PP; PLC challenge + 20 mg/kg Q4-15-2A7P from days 1-35), and therapy peptide group (TP; PLC challenge + 20 mg/kg Q4-15-2A7P from days 23-35). PLC (150 U/mL) was orally administered from days 19 to 21. Results showed that feed intake in the PP group from days 1 to 27 recovered to NC levels, whereas the PC group exhibited severe intestinal lesions. At 35 days, ileal lesion scores in the PP and TP groups were comparable to those of healthy birds. At 28 days, PP and TP groups had lower expression of inflammation-associated genes in the ileum, and the PP group showed increased expression of tight junction genes. The expression of tight junction-associated genes in the ileum were not induced in the TP group at 28 days, as opposed to the PP group. The microbiota in the PP and TP groups closely resembled that of the NC group. In conclusion, both preventive and therapeutic peptide strategies effectively mitigated PLC-induced pathology, with the PP group showing the most pronounced gut health improvement.

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ABSTRACT Pre-slaughter phases of broiler chickens can significantly compromise animal welfare, as conventional catching methods often raise ethical, physical, and moral concerns. Mechanized catching has been emerging as a viable alternative with potential to reduce these issues and improve animal treatment. This study aimed to assess the Brazilian population’s perception of broiler chicken welfare and identify factors influencing preferences for manual or mechanized catching methods, focusing on socioeconomic, demographic, and cultural aspects. A structured questionnaire was administered to a sample of 508 individuals. Variables examined included socioeconomic class, demographic profile, diet type, involvement in poultry farming, and willingness to pay more for products with certified animal welfare. Data were analyzed using Chi-square tests to assess associations between categorical variables. The findings revealed a strong preference for mechanized catching, which was perceived as more comfortable and less physically harmful to chickens. However, it was also associated with perceptions of increased fear and emotional distress. Concerns related to animal welfare and confidence in preserving bird health during and after catching were significantly affected by the place of residence, but not by diet. Although animal welfare is not a primary factor for most consumers at the time of purchase, many respondents (62%) expressed a willingness to pay more for products with certified animal welfare. Mechanized catching remains relatively unfamiliar to Brazilian consumers, but the study suggests that increasing awareness of its benefits could enhance understanding and support the development of public policies and communication strategies to promote better welfare practices in the poultry industry.

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ABSTRACT The Caucasian pheasant (Phasianus colchicus colchicus) is a Phasianidae family poultry species that is an important animal-based protein source. This study aimed to estimate the growth traits of body weight (BW) in pheasants using Logistic (L), Gompertz (G) and Von Bertalanffy (VB) models. A total of 1,765 data records of BW from hatching to 18 weeks of age were collected from the pheasant population in the Alternative Poultry Unit at Prof. Dr. Hümeyra Ozgen Research and Application Farm, Selҫuk University, Türkiye. The results showed that the coefficient of determination (R2) value in each model was 0.94. However, the lowest values for Akaike’s information criterion (AIC) and Bayesian information criterion (BIC) among models were found in the G model. In general, the pheasants had the weight of inflection (Wi) and time of inflection (ti) of 535.11-592.00 g and 9.00-10.01 weeks, respectively. Moreover, about 80-90 g/week of the average weight gain was reached at the inflection point of the pheasants. In conclusion, the parameters of the goodness-of-fit criteria (AIC and BIC) indicated that the G model was the best formula to predict the growth curve of body weight in Caucasian pheasants.

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ABSTRACT This study evaluated the efficacy of an attenuated coccidiosis vaccine containing early-maturing Eimeria strains, combined with a nutritional additive, as an alternative to anticoccidial drugs in broilers. A total of 672 male Ross chicks were allocated in a 4×2 factorial design (4 control programs: anticoccidial, additive + anticoccidial, vaccine and additive + vaccine vs. challenged or not with live coccidiosis vaccine and Escherichia coli), totaling eight treatments with six replicates of 14 birds. Data were analyzed using ANOVA (GLM procedure, SAS software). Challenged birds showed reduced productive performance (p<0.05) regardless of treatment, with no differences between control programs. The vaccine improved jejunal morphometry, notably villus width and crypt depth, and was associated with enhanced regenerative capacity at 28 days. No significant effects (p>0.05) were observed for mitotic index. Serum FITC-d levels were lower (p<0.05) in challenged birds, and foot coloration was higher with the vaccine plus additive. These findings support the use of an early attenuated vaccine as a viable and effective alternative to traditional anticoccidials, especially when paired with nutritional additives.

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ABSTRACT Artemisia vulgaris (mugwort) and Ipomoea aquatica (water spinach) are rich in nutrients and phytochemicals, yet their combined effects with multi-probiotics on laying hens remain unexplored. This study evaluated the effects of fermented mugwort and water spinach juice (FMW) on performance, physiological traits, and gut microbiota in laying hens. Sixty 67-week-old Lohmann Brown hens were randomly allocated to three dietary treatments for four weeks, with five replicates of four birds each: a control diet, 0.1% FMW, and 0.2% FMW. FMW supplementation had no significant effect on laying performance, organ weights, tibia traits, or cecal CFU counts. However, average egg weight (AEW) was higher in the control and 0.1% FMW groups than in the 0.2% group (quadratic, p<0.01). Yolk height was greater in the 0.1% group than in the control (quadratic, p<0.05), while the 0.2% group had the highest eggshell strength (linear, p<0.05; quadratic, p<0.001) and thicker shells than the 0.1% group (quadratic, p<0.01). Serum total cholesterol was higher in the 0.1% group than in the 0.2% group (quadratic, p<0.05), and HDL-cholesterol was also higher in the 0.1% group than in the control (quadratic, p<0.05). The 0.2% group showed reduced ileal villus height versus control and 0.1% (linear, p<0.01), and a lower VH/CD ratio than the 0.1% group (quadratic, p<0.01). Both FMW groups increased Bacteroides abundance (linear, p<0.05), and Mediterraneibacter tended to increase (p=0.059). These results suggest that FMW has potential as a functional feed additive for improving egg quality, enhancing HDL-cholesterol levels, and modulating gut microbiota in laying hens.

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ABSTRACT The current study aimed to evaluate the effects of nutritional selenium (Se) supplementation on the hatching characteristics, chick quality traits, and selenium retention of Japanese quails. A total of 250 adult Japanese quails were randomly assigned to five dietary treatments: sodium selenite (SS, 0.30 ppm), selenium methionine (SM, 0.30 ppm), selenium yeast (SY, 0.30 ppm), selenium nanoparticles (SNPs, 0.30 ppm), and a control group without Se supplementation, with five replicates of 10 birds each (7 females and 3 males), under a completely randomized design. Hens fed SY and SNPs produced significantly more settable eggs compared to the other groups. Supplementation with SNPs improved fertility, hatchability, and reduced embryonic mortality. Chicks hatched from SNP-fed hens exhibited greater body weight, longer chick length, and longer leg lengths, with similar leg length benefits observed in the SY group. A higher proportion of A-grade chicks was recorded in the SM, SY, and SNP groups compared to other groups. Birds fed SNPs retained more selenium in the breast muscle, feathers, liver, and heart, whereas selenium retention in the kidney was highest in the sodium selenite-fed group. Plasma selenium levels were notably higher in the SNP-supplemented group, and hens receiving SNPs laid eggs with the highest selenium concentrations in the albumin, yolk, and shell. It was concluded that dietary supplementation with organic selenium, particularly SNPs, is a highly effective strategy to enhance hatching traits and minimize embryonic mortality in Japanese quails.

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ABSTRACT This study investigated the effect of spraying duck hatching eggs with distilled water or apple vinegar solution on the hatching and post-hatch performance. 120 eggs from breeder Pekin ducks at 64 weeks of age were used. The eggs were weighed using a scale with a precision of 0.1 g and divided into three groups with 40 eggs per group. The eggs of group 1 (Non-sprayed, NS) were incubated without any spraying practices. The eggs of group 2 (Water-sprayed, SW) and group 3 (Sprayed with apple vinegar, SA) were sprayed with distilled water and a solution of distilled water (250 mL) + apple cider vinegar (5 mL) between embryonic days (ED) 8 and 24, respectively. The eggshell temperature, hatchability of set and fertile eggs, and chick yield were significantly higher in the SW and SA compared to eggs of the NS eggs (p≤0.05). However, the best hatching traits, eggshell temperature, and chick yield were identified in SW. Body weight and body weight gain at 14 days of age and the total average body weight were significantly highest, and lowest in ducks of the SW and SA, respectively (p≤0.05). In addition, the metatarsal temperature was significantly lowest and highest in ducks of the NS and SW, respectively (p≤0.05). The hot carcass weight and breast weight were higher in ducks of the SW and SA groups compared to NS ducks (p≤0.05). The thigh and wing yield were significantly higher in SA ducks compared to ducks from the other incubation treatments. However, the back weight and yield were significantly higher in NS ducks than in ducks in the SW and SA treatments (p≤0.05). Spraying duck eggs with water and apple vinegar solution between ED 8-24 improves embryonic heat loss, hatching traits, chick yield, and chick weight at hatch. Moreover, spraying with water is more beneficial for improving post-hatch growth performance, while the application of both apple vinegar solution and water during incubation seemed beneficial for adaptation to post-hatch stress conditions. Additionally, spraying eggs with water and apple vinegar solution had the potential to improve most of the carcass and organ traits. It also tended to increase most of the texture profile values of the breast meat, cooking loss, and meat pH, as well as improve breast meat color traits.

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ABSTRACT This study was conducted to determine the effect of different anti-stressors on the performance and physiology of cyclic heat-stressed laying quails. Three hundred 7-week-old laying quails were randomly assigned to six treatments of five replicates, which were restrictedly fed the same basal diet for 6-weeks. Treatments were: Negative Control (NC), drank tap water with no additive; Positive Control (Vit C), tap water plus Vit C at 0.35g/L; OPE 1, tap water plus aqueous orange peel extract at 2cc/L; OPE 2, tap water plus aqueous Orange peel extract at 4cc/L; VeO 1, tap water plus VeO Premium at 2cc/L; VeO 2, tap water plus VeO Premium at 4cc/L. Growth and productive performance were measured weekly, egg quality indices biweekly, and serum biochemical and jejunum morphometrics were measured at the end of the trial. Compared to NC group, birds of all the supplemented groups had significantly better feed conversion ratio (FCR); laid more and heavier eggs with thicker shells, higher Haugh units, and darker yolks; had significantly lower serum levels of glucose, aspartate aminotransferase (AST), and low-density lipoprotein (LDL); and higher serum levels of globulin, calcium, triiodothyronine (T3), and immune titers against NDV and IBDV. Birds given all the anti-stressors showed significantly increased Jejunum villus height (VH), villus to crypt depth ratio (VH: CD), and villus surface area compared to the NC group. This suggests that OPE and VeO Premium are good tools to eliminate the negative effects of cyclic heat stress on layer quails.

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ABSTRACT This study examined the effects of palm oil supplementation on the performance of laying hens, egg quality, and yolk fatty acid composition. A total of 120 Lohmann LSL-Lite layers aged 25 weeks were assigned to four dietary treatment groups (T1-T4), each receiving varying levels of palm oil supplementation (0%, 1.5%, 3.0%, and 4.5%). Each treatment had three replicates with 10 hens per replicate, following a completely randomized design. The T3 group exhibited the highest feed intake, while the final body weight was best in the T1 and T4 groups. Weekly egg production improved in T2, while T3 had the highest average egg weight, egg mass, and improved feed conversion ratio. Hen-day egg production was enhanced in T2, T3, and T4, whereas hen-house egg production was higher in T2 and T4. In terms of egg quality, T3 had the highest egg weight, while T2 and T3 had superior eggshell thickness. Additionally, T2 showed greater eggshell weight, albumen height, and yolk index, whereas yolk height was highest in T4. The T3 group also had the highest Haugh unit, yolk diameter, and yolk color, while yolk and albumen weight were greater in T1 and T3. Saturated fatty acids increased with 4.5% palm oil, while unsaturated fatty acids were significantly higher in T3. Among the groups, omega-3 fatty acids were highest in T2, whereas omega-6 fatty acids were highest in T4. In conclusion, 3.0% palm oil supplementation effectively improved egg production, feed efficiency, egg quality, and yolk fatty acid profile.

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ABSTRACT In this study, the effects of adding phytase to quail diets at different rates on performance parameters, carcass parameters, and liver, intestinal cells, and intestinal villi lengths were investigated. A total of 180 1-day-old quails (Coturnix coturnix Japonica) were used as the animal material of the study. The animals in the study were divided into 3 groups: control and experimental, and groups were allotted into cages with 6 replications containing 5 males and 5 females each. In the experiment, quail chicks were fed with one of three experimental diets from the first day of the experiment: the first group was fed with a normal phosphorus diet without any additives. The second group was fed a 150 FTU/kg phytase added diet. The third group was fed a diet with 300 FTU/kg phytase added to it. The experimental period lasted 6 weeks. The phytase used in the study was produced by the researchers. At the end of the study, the animals with the highest body weight gain and feed consumption were in the 300 FTU/kg group, while those with the lowest body weight gain and feed consumption were in the control group. However, there was no difference between the groups in terms of feed conversion ratio and cold carcass, thigh, and wing weights. In addition, the longest villus length was observed in the diet with the addition of 300 FTU/kg of phytase. As a result, phytase supplementation was shown to have a positive effect on both growth performance and the intestinal health of quails.

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ABSTRACT Mycoplasma gallisepticum is a common cause of chronic respiratory disease in commercial poultry, affecting both egg and meat production. The infection is often complicated by secondary bacterial and viral pathogens, adding complexity to the diagnosis. Administration of antibiotics to mitigate clinical disease outcomes and reduce production losses poses threats of increased antimicrobial resistance. PCR-based diagnostic techniques are of paramount significance for early and sensitive detection of M. gallisepticum, in-time management for disease therapeutics. So far, a number of molecular techniques have been devised for quick, efficient and cost-effective detection, including insulated isothermal PCR (iiPCR). The current study was performed to validate iiPCR in comparison with real-time PCR (qPCR) and conventional PCR (con-PCR). Analytical sensitivity was evaluated by preparing 10-fold diluted concentrations of M. gallisepticum F (live vaccine), and three field isolates in M. gallisepticum broth (100-107 CFU/ml). Diagnostic performance of iiPCR was assessed using 95 field samples. The analytical and diagnostic performance of the assays was evaluated and compared with the gold standard that is qPCR. In the present study, the detection limit of iiPCR was found to be comparable with that of qPCR. Statistical analysis and comparison of reliability of different PCR-based techniques for detection of M. gallisepticum provided almost perfect agreement between all techniques. It was found that iiPCR can be a good, efficient and relatively cost-effective alternative to qPCR. It can be employed for initial detection of infectious organisms, leading to effective management strategies.

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ABSTRACT This study aimed to investigate the feed intake, feed conversion ratio, growth performance, first laying age, and egg quality of Japanese quail lines. The study material consisted of Yamtar-I and Yamtar-II Japanese quail lines bred on a private farm in Karaman province, along with a control group derived from these lines. From 0-5 weeks of age, Yamtar-II showed higher live weight than the control group at 5 weeks, though averages were similar during the first four weeks of age (p<0.01). Growth and fattening analysis revealed significant differences in live weight gain and daily live weight gain between 3-4 and 4-5 weeks of age (p<0.05), while feed intake and feed conversion ratios were similar. Egg production was monitored from first laying to 93 days of age, with quails housed in 1:2 (male/female) single mating cages. At 10 weeks of age, egg quality characteristics were analyzed using 20 quail eggs per group. The control group showed delayed egg laying (p<0.01), and lower egg production (p<0.05) compared to the other groups. Significant differences in egg and yolk weights (p<0.01) were found among the groups. On the other hand, shape index, shell thickness, shell ratio, yolk ratio, Haugh unit, albumen weight, and albumen ratio were similar. In conclusion, Yamtar-I and Yamtar-II lines, which were obtained by selection by the breeder, showed no significant differences in fattening. Moreover, Yamtar-I have demonstrated better egg production and quality characteristics compared to the control group. These findings suggest that applying a conscious selection strategy could enhance commercial quail breeding potential.

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ABSTRACT The type of carbohydrate diet is an important factor in methane (CH4) emission from livestock. In this study, a structural carbohydrate (rice hull) was tested as a feed ingredient and compared with the use of a non-structural carbohydrate supplemented to cecal contents to study the effect of carbohydrates type and levels on methane production from the caecum content of White Roman geese. Four experiments were conducted to determine the methane production in the cecal material from White Roman geese. In Experiment I, the methane production in vitro from cecal content from the basal diet supplemented with 8% rice hull did not increase compared with the basal diet. In Experiment II, non-structural carbohydrates such as glucose, starch, and sucrose could increase the methane production of cecal contents in vitro (p<0.05), and the mean methane production was such that glucose > starch > sucrose. In Experiment III, the cumulative methane production in cecal contents added with glucose in White Roman geese for different incubation times showed that the methane production had the largest increase 0.5 hour after adding the glucose treatments. It also indicated that glucose could be fermented and converted into methane after half an hour of incubation. In Experiment IV, methane production from cecal contents increased with the quantity of glucose (p<0.001) in a dose response manner of additives, whereas methane concentration did not increase with the dose of glucose in geometric progression. These results suggest that rice hulls can substitute part of the feed of White Roman geese to reduce methane emissions. Methane production rates from cecal contents depend on the type of carbohydrate and the additional glucose in cecal can cause issues by increasing methane emission from birds. To conclude, it is suggested that the speed of decomposing polysaccharide into monosaccharide by digestion may be a key to determine methane production rate from cecal content in goslings.