Mature Weight in Hereford Range Cows—Heritability, Repeatability, and Relationship to Calf Performance

Abstract
Data on cow weights and calf weights and scores collected at the United States Range Livestock Experiment Station, Miles City, Montana were used to study mature weight of cows and its relations to calf production. Cow weights increased with age up to 8 years, and then declined slightly. Heritabilities of average spring and fall weights of cows were estimated at 0.75 and 0.73, and heritabilities based on single records were estimated at 0.57 and 0.62, respectively. Although fairly small, correlations between cow weights and their calves' weights and gains indicate that heavier cows tend to produce heavier, faster-gaining calves. There were some indications that increases in cow weight over the winter months were positively associated with heavier, faster-gaining calves, whereas increases in cow weight during the suckling period were negatively correlated with calves' weights and gains. Copyright © . .