This study was conducted to evaluate the effects of lead spheres placed in the uterus to simulate pregnancy and of growth promoter on carcass weight, carcass conformation, carcass and leg lengths, beef round and fat thickness, percentages of bone, muscle, and fat, and thawing and cooking losses. Twenty Murrah buffalo heifers averaging 20 months of age were randomly assigned to one of three treatments: control (non-pregnant heifers but with ovarian activity - NP), lead (100 lead spheres placed in the uterus - L), or growth promoter (GP). After 84 days in feedlot the average slaughter weights were 414.8, 451.8, and 422.6 kg for heifers on NP, L, and GP treatments, respectively. No significant differences were observed among treatments for slaughter body weight (429.8 kg), hot carcass weight (209.0 kg), carcass conformation (8.2 points), carcass length (122.9 cm), legs length (68.1 cm), cushion thickness (25.0 cm), loin eye area (57.1 cm²), fat thickness (4.8 mm), percentages of muscle (60.6%), bone (18.9%), and fat (20.5%), muscle/bone ratio (3.2), muscle plus fat/bone ratio (4.3), thawing loss (9.3%), cooking (23.4%) and freezing to cooking losses (30.5%), tenderness (7.8 points), juiciness (7.0 points), and flavor (6.7 points). It was concluded that the use of growth promoter or lead spheres in the uterus had no significant effects on the studied variables.
beef round; cooking; physical composition; tenderness
