What’s new in research?
Our experts participate in conferences around the world to keep up with new knowledge and tools developed in dairy production. Here is an innovative research project from the 2022 American Dairy Science Association annual meeting. Let’s take a look at this compelling new study related to calves and heifers.
Is gestation length the same for dairy and crossbred calves?
Insemination of dairy cows and heifers using semen from beef breed sires is gaining in popularity. Field observations suggest that the genetic of beef cattle can affect calving performance, but there was little research on this subject.
A group of researchers at the University of Pennsylvania (Basiel et al.) analyzed thousands of data points from dairy farms in their state to determine whether gestation length and dystocia in Holsteins were influenced by beef breed sires versus Holstein sires. They found that the use of beef breed sires did not cause a higher incidence of dystocia or stillbirths than the use of Holstein sires. When grouped per breed type, it was reported that crossbred calves had 2 more days of gestation than dairy calves.
However, when gestation length was analyzed by breed, the researchers observed that Holstein calves had the shortest gestation (276 days), while Charolais (277 days), Angus (277 days), Simmental (279 days) and Wagyu (285 days) calves had longer ones. These results are relevant because, depending on the breed of the beef sire and the intensity of its use to breed cows, adjustments could be made based on the length of the dry period and related practices, such as the transfer of cows to the close-up group*.