Submitted to: Journal of Animal Science Supplement
Publication Type: Abstract Only
Publication Acceptance Date: 3/15/1995
Publication Date: N/A
Technical Abstract: Spring born steer calves sired by either Angus (A), Brahman (B), Senepol (S) or Tuli (T) bulls were used to determine the effect of sire breed on feedlot performance and carcass characteristics. Angus cows were used as a common dam for the calves, which were reared in a semiarid range environment, weaned in the fall and transported to El Reno, OK (800 km). Upon arrival the calves were blocked by sire breed and randomly assigned t one of three the following stocker treatments for the winter grazing period: 1) Native range plus protein supplement; 2) Winter wheat pasture; 3) Limit fed a high concentrate diet. During the spring/summer grazing period, all calves were managed as one group and grazed cool season annuals and warm season perennials until entering the feedlot in July of each year (1993 and 1994). Steers were fed a high energy diet containing 1.66 Mcal of Net Energy for gain/kg of DM for 113 d. Calves sired by B bulls were heavier (P<.01) at the initiation and at the end of the feeding period tha the other three sire groups. Average daily gain was poorest (P<.01) for the T sired calves and greatest for the A and B sire calves. Dressing percentage average 62.6 and was not different among sired breeds. Hot carcass weights reflect the differences in final finish weights. Yield grade and fat thickness show that the B sired calves had more finish than the A, S, or T sired calves. These data show that Senepol and Tuli sired calves have carcass characteristics similar Angus sired calves, but lower feedlot performance.