|Mayeux Jr, Herman|
Submitted to: American Society of Animal Science Southern Section Meeting
Publication Type: Abstract Only
Publication Acceptance Date: October 15, 2003
Publication Date: February 14, 2004
Citation: Phillips, W.A., Coleman, S.W., Riley, D.G., Chase, C.C., Mayeux, H.S. 2004. Evaluation of Romosinuano as straightbreds and crossbreds with Angus and Brahman: Stocker and feedlot gains [abstract]. American Society of Animal Science Southern Section Meeting. Paper No. 21. Technical Abstract: Genetic adaptation to tropical conditions is an essential component of beef herds in the Southern US. Calves generated from these herds are transported to more temperate climates for growth and development. The objective of this experiment was to compare stocker and feedlot performance of steers from temperate (Angus) and tropical (Brahman and Romosinuano) breeds reared in a semitropical environment, but grown and finished in a temperate environment. In the fall of 2002, steer calves (n=143) of Angus (A), Brahman (B), Romosinuano (R), and all two breed crosses (AB, AR, BA, BR, RA, and RB) born and reared at Brooksville, FL were transported 2025 km to El Reno, OK. Steers grazed winter wheat pastures from November 13 through May 6 before entering the feedlot. Data on all purebred calves and crossbred calves sired by A bulls is presented in the table below. SWT WADG SADG FLADG FLFWT Breed (kg) (kg/d) (kg/d) (kg/d) (kg) BB 247a 0.58c 1.06b 0.97b 269b RR 212b 0.71bc 1.09b 1.08ab 355b AA 229b 0.95a 1.25ab 1.06ab 408a AB 276a 0.79b 1.29a 1.13a 439a AR 255a 0.83ab 1.28a 1.17a 421a SEM 9.9 0.05 0.06 0.08 10.4 At the beginning of the grazing period (SWT), purebred R and A calves were lighter (P < 0.05) than purebred B and crossbred calves sired by A bulls. Rate of gain (WADG) during the winter grazing period (November through Mid-March) was lower (P < 0.05) for purebred B and R calves than for purebred A calves. Rate of gain (SADG) during the spring (March and April) followed a similar trend among breeds to those observed during the winter. During the feedlot phase, calves were fed for an average of 123 d. Feedlot ADG (FLADG) of purebred R steers was intermediate to purebred B and crossbred calves sired by A bulls, but similar to purebred A calves. Final feedlot BW (FLFWT) was higher (P < 0.05) for A and A sired calves than for purebred R and B calves. Purebred R and B calves had similar stocker and feedlot performance. Angus sired calves from R and B dams performed as well as purebred A calves.