Date of this Version
Roman L. Hruska U.S.Meat Animal Research Center. Agricultural Research Service. U.S. Department of Agriculture. Clay Center. NE 68933; Standardization Branch. Meat Quality Division. Food Safety and Quality Service. U.S. Department of Agriculture; Kansas State University. Manhattan; and the University of Nebraska. Lincoln. cooperating (October 1981).
This report provides reproduction and maternal performance data for cows in each cycle and phase of the Germ Plasm Evaluation Program.
The cattle Germ Plasm Evaluation Program has been conducted in three cycles. Cycle I involved breeding Hereford, Angus, Jersey, South Devon, Limousin, Simmental, and Charolais bulls by artificial insemination (AI) to Hereford and Angus cows to produce three calf crops (Cycle I, Phase 2) in the spring of 1970, 1971 and 1972.
Cycle II. initiated with the 1972 breeding season involved the Hereford and Angus cows used in the first cycle. These cows were bred by AI to Hereford, Angus, Red Poll, Brown Swiss, Gelhvieh, Maine Aniou, and Chianina sires to produce two calf crops (Cycle II. Phase 2) in the spring of 1973 and 1974. In addition, in Cycle II, Phase 2, Red Poll and Brown Swiss cows were added to the program and mated to Hereford, Angus, Red Poll, and Brown Swiss sires in a four-breed diallel crossbreeding experiment.
Cycle III was initiated during the 1974 breeding season. In Cycle III, the Hereford and Angus cows used to initiate Cycles I and II were mated by AI to Hereford, Angus, Pinzgauer, Tarentaise, Rrahman, and Sahiwal sires to produce two calf crops (Cycle III. Phase 2) in the sprinq of 1975 and 1976.