Date of this Version
Agricultural Research Service, U.S. Department of Agriculture (March 1974).
The cattle germ plasm evaluation program at the U.S. Meat Animal Research Center is designed to characterize breeds representing different biological types in the full spectrum of economic traits relating to growth, feed efficiency, reproduction, maternal ability and carcass and meat traits. The basic objective of this program is to develop an understanding relating to optimizing such biological factors as cow size, milk level, etc., in different feed environments and production situations.
The program was started with the 1969 breeding season. The first cycle involved breeding by artificial insemination (AI), Hereford, Angus, Jersey, South Devon, Limousin, Summental and Charolais bulls to Hereford and Angus Cows. The three calf-crops for Cycle 1, Phase 1 of the program were born in March, April and early May of 1970, 1097, and 1972 and were weaned in October or November at approximately 200 days of age. All male calves were fed out as steers and slaughtered to evaluate growth, feed efficiency and carcass and meat traits. All female progeny were retained for evaluation of reproduction and maternal traits (Cycle 1, Phase 2). Mating plans are given in the appendix tables on the part of the program for which results are presented in this report.