Optimizing Seasonal Operations and Bull Management in Spring-Calving Herds: Insights from Kansas State University Experts

By Trish Svoboda

In agriculture, whether farming or ranching, operations follow seasonal shifts. For spring-calving commercial herds, summer sees cows, calves, and bulls grazing on pastures while cows conceive next year’s calves. Kansas State University’s Beef Cattle Institute advises a 50- to 70-day calving window, as discussed on a recent Cattle Chat podcast.

Even though the aim is a brief calving season, K-State veterinarian Bob Larson emphasizes the value of bred cows over open ones (ones who haven’t conceived). Keeping bulls in breeding pastures beyond 60 days maximizes pregnancy rates, though late-bred females may be culled. Phillip Lancaster, K-State beef cattle nutritionist, acknowledges occasions when bulls must be removed from pastures.

In mid to late summer, Lancaster recommends separating younger bulls for supplementary feeding as forage quality declines, preventing them from becoming too thin, crucial during their growth phase. He also advises reducing the number of bulls in pastures with multiple males to avoid fighting, suggesting leaving one or two older bulls to breed remaining open cows, balancing value retention with injury risk reduction.

Another factor to consider is the availability of labor to remove the bulls from the pasture, Larson pointed out. He suggested evaluating the bulls during routine herd movements, like applying fly control, to efficiently utilize available labor.

Larson emphasized flexibility in bull management, noting that while a 60-day calving season is preferred, the breeding season doesn’t necessarily need to be constrained to 60 days.

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