This study was conducted to evaluate the effect of pregnancy simulation (placement of 100 lead spheres in the uterus-LEAD) and ovariectomy (OVAE) on traits of carcass and meat of heifers finished in feedlot. Animals not pregnant and with intact ovary were used as the control (CTRL). Nineteen crossbred heifers (½ Nelore x ½ Red Angus) averaging 18 months of age and 257.8 kg of body weight were used. Animals were fed a diet containing (% DM): 41% of corn silage and 59% of soybean meal, corn, and trace minerals. No significant differences were observed for slaughter weight, which averaged 324.1, 323.3, and 303.3 kg, respectively, for CTRL, LEAD, and OVAE treatments. Similarly, there were no significant differences among treatments for the following variables: hot carcass weight (171.1 kg), carcass length (113.8 cm), hind limb length (68.2 cm), cushion thickness (21.0 cm), loin eye area (57.3 cm²), fat thickness (4.0 mm), percentages of muscle (62.6%), bone (16.0%), and fat (21.7%), muscle/fat ratio (3.9), muscle plus fat/bone ratio (5.3), cooking losses (24.3%), freezing to cooking losses (30.9%), tenderness (7.1 points), juiciness (6.6 points), and flavor (6.6 points). The color, texture, and marbling parameters also did not differ averaging 4.0, 4.4, and 3.7 points, respectively, among treatments. In addition, no significant differences were found to contents of ash (1.1%), crude protein (21.8%), total fat (2.9%), and cholesterol (49.6mg/100g) in the Longissimus dorsi muscle. Thus, it can be concluded that estrus did not affect carcass characteristics.
carcass; crude protein; moisture; physical composition; tenderness
