Getting first-calf heifers bred back early in the breeding season is essential to successful beef cow reproduction and herd performance. When first-calf beef heifers are bred later than the rest of the herd, it can have a negative effect on their reproduction for a lifetime.
Late Calving for a Lifetime
It takes time for a beef cow to start cycling again after giving birth to a calf. If a first-calf heifer is 21-days or more behind the rest of the herd in getting bred, she may not be fully cycling again at the start of the next breeding season and will more likely calve late throughout her life.
Lower Weaning Weight
Many operations wean most, if not all, calves at the same time, so if a heifer calves 21 days later than the rest of the herd, that calf is going to be younger and lighter at weaning. Figuring two pounds (0.9 kg) of weight gain per day, the calf could have 42 pounds (19 kg) less saleable weight at weaning.
Reduced Herd Longevity
Research conducted by the United States Meat Animal Research Center (USMARC) and South Dakota State University (SDSU) show that heifers that calved with their first calf during the 21-day period of the calving season have increased longevity in the herd, compared to heifers that calved in the second 21-day period or later. In the USMARC herd, average herd longevity dropped by seven percent for heifers who calved in the second period and 21-day calving period by 12 percent for those that calved in the third calving period. In the SDSU herd, heifer herd longevity dropped by 24 percent for heifers that calved in the second or subsequent 21-day calving period.
Reduced Cow Profitability
While economics vary, research shows that heifers don’t offset the cost of their own development and become profitable until they’ve weaned at least to 3 to 5 calves. While it’s necessary to cull cattle in order to advance genetics within herds, there are lost profit opportunities in terms of weaning weights and herd longevity if heifers are not bred in the first 21-day breeding period.
How Performance Trace Minerals Help Improve Beef Cow Reproduction
It is critical for a beef cattle producer to have cows that are calving on a calendar-year basis. Anything you can do to help a cow breed back early during the breeding season is going to make her a more profitable and more efficient cow in terms of her lifetime production.
In a study that was conducted at the University of Florida’s Range Cattle Research and Education Center in Ona, Fla., cows 3 or 4 years of age fed performance trace minerals from Availa® 4 had increased pregnancy rates and lower calving intervals than cows that were fed inorganic trace minerals. Over a 3-year period, the cows that were fed Availa-4 had a pregnancy rate that averaged 18 percent higher than the cows that were fed inorganic trace minerals. The calving interval for cows that were fed trace minerals from Availa-4 was more than 16 days shorter on average over the same 3-year period.
Feeding cows performance trace minerals early in their life is essential, as younger first and second calf cows undergo greater production stress than mature cows. The response to trace minerals during this time in their development is often more prominent.