By Ryan Sterry
Raising replacement heifers costs money. When done correctly, the payoff is an improvement in your herd’s productivity and longevity. Post-breeding management is crucial, but often overlooked in a heifer development program.
Post-breeding management begins with performing a pregnancy diagnosis to identify non-pregnant heifers. Identifying open heifers sooner rather than later allows you to make decisions to market them as heavy feeders or transition to feed on your own farm. Delaying this decision may result in marketing heifers that are discounted due to heavy weights and large frames before they are placed on feed. To learn more about pregnancy diagnosis methods and timing, read the UW-Madison Extension Livestock article “Determining Cattle Pregnancy Status”.
Recording breeding dates or having fetal aging estimated by a veterinarian can inform decision-making in retaining or marketing bred heifers. A compilation of season-long heifer pregnancy rate data by Moorey and Biase (2020) found a range of 64 to 95%, with an average of 85%, throughout the first breeding season. Looking closer, first-cycle conception rates are often between 60 and 70%. A study by Cushman et al. (2013) observed 7% of heifers conceiving during their third breeding cycle, despite being exposed during their first and second cycles. When the number of pregnant heifers exceeds the number of replacements needed, timing of conception (early or late in breeding season) can be added to the list of selection criteria. In this example, the 7% that conceived in the third cycle would be the first heifers to be scrutinized more closely for marketing.
The advantages of selecting heifers that conceive early versus late include:
- Weaning heavier calves
- Greater fertility in their second breeding season
- Having greater lifetime productivity
- Tighter grouping to manage calving
Source : wisc.edu