Influence of first calving date on stayability and productivity in Bos indicus-Bos taurus crossbred cows

Authors: Engle, Bailey; GILL, CLARE - Texas A&M University; SAWYER, JASON - East Foundation; RILEY, DAVID - Texas A&M University; SANDERS, JAMES - Texas A&M University; HERRING, ANDY - Texas A&M University

Submitted to: Translational Animal Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/15/2026
Publication Date: 4/28/2026
Citation: Engle, B.N., Gill, C.A., Sawyer, J.E., Riley, D.G., Sanders, J.O., Herring, A.D. 2026. Influence of first calving date on stayability and productivity in Bos indicus-Bos taurus crossbred cows. Translational Animal Science. Article txag051. https://doi.org/10.1093/tas/txag051.
DOI: https://doi.org/10.1093/tas/txag051

Interpretive Summary: Reproductive longevity, or how long a cow remains reproductively capable, is one of the most important influences on herd profitability. Therefore, it would be advantageous to identify traits correlated to longevity that can be measured and used for selecting the next generation of herd sires and dams. Here, a herd of B. indicus–B. taurus crossbred cows (n = 293) were used to characterize the effect of first calving season period on measures of future cow productivity. Calving period was assigned by designating each of the calving seasons into four 21-d periods, and each cow was assigned a score of 1-4 for the relative time period of her first parity. There was a clear advantage to heifers calving within the first 21 d of their first calving season. These females were more likely to meet reproductive longevity benchmarks, had significantly higher average lifetime calf crop weaned, and their first calves were significantly heavier at weaning. Due to the advantages to both maternal productivity and calf performance, calving within the first 21 d of an annual calving season is expected to increase the herd longevity of these females, and may be considered as an early-in-life evaluation criterion when selecting for longevity or lifetime productivity in B. indicus-B. taurus crossbred beef cows.

Technical Abstract: Reproductive longevity is directly related to a cow’s lifetime productivity and cumulative economic value, making it one of the most important influences on herd profitability. Therefore, it would be advantageous to identify component traits correlated to longevity that can be measured and used as selection criteria in young replacement prospects. A herd of Bos indicus–Bos taurus crossbred cows (n=293) were used to 1) characterize the relationship between first-parity calving season period with subsequent longevity and cow productivity and 2) assess the influence of the cow’s birth period on her potential for stayability and productivity. Calving period was assigned by designating each of the calving seasons into four 21-d periods, and each cow was assigned a score of 1–4 for the time period of her first parturition and her own birth. The relationship between calving period and stayability to ages 3, 4, 5, 6, and 7 yr of age, first and lifetime average calving intervals, first-calf weight, lifetime average calf weights, and cumulative calf weight weaned were evaluated. There was a clear advantage for heifers calving within the first 21 d of the calving season as their calves were heavier at weaning (P<0.05) and demonstrated greater preweaning weight gain (P<0.05). This was further reflected in terms of long-term productivity, as cows that calved in the first 21-d period of their first-parity calving season produced greater average calf crop weaned (P<0.05) and greater cumulative calf crop weaned (P<0.05) than cows that calved later in their first season. These early-calving heifers were more likely to meet stayability benchmarks at 3, 4, 5, 6, and 7 yr than heifers calving at later periods in the season (P < 0.05). Earlier born cows had a higher probability of heifer pregnancy (P < 0.05) and were heavier at first-calf weaning (P < 0.05), possibly because they were older at first calving (P < 0.05). Due to the advantages to both maternal productivity and calf performance, calving within the first 21 d of an annual calving season is expected to increase the herd longevity of these females, and may be considered as an earlier-in-life evaluation criterion when selecting for longevity or lifetime productivity in B. indicus-B. taurus crossbred beef cows.