A.I. & Breeding

It’s been nearly 75 years since the introduction of frozen semen for artificial insemination (A.I.) and 10 years since genomic selection. During those years, the U.S. has catapulted itself to the position of world leader in bovine genetics, which is a comfortable position to be in.

During the 2019 Vita Plus Dairy Summit, Vita Plus Dairy Specialist Randall Greenfield teamed up with his counterpart on the beef side, Chad Howlett, to tackle the topic of using beef semen to manage dairy heifer herd inventory, and the opportunities and challenges that come along with the resulting crossbred calves.

In 2018, U.S. Holstein cows in the Dairy Herd Improvement (DHI) program remained in the milking herd for an average of 28.4 months. Looking back to those born in 1975, they stayed an average of 34.4 months – a full half a year longer. This interval, coined Productive Life, runs from the day of calving in the first lactation to the day the cow left the herd. Some have suggested cows aren’t staying as long because “they are subjected to more stress.”

CDCB announces updates alongside the December genetic evaluations. These announcements relate to updated crossbred evaluations, as well as foreign fertility evaluations.

Dairy cows that become pregnant within a reasonable time frame produce more milk over their lifetime and are less likely to be culled from the herd. Thus, the goal is to have as many cows pregnant as possible by the time they are less than 150 days in milk.

Achieving an appropriate calcium balance in dairy cows is critical near calving, but not only to ensure a healthy transition to lactation. According to a new study from the University of Illinois, calcium added to acidified prepartum diets can improve a whole suite of postpartum outcomes, including lower rates of uterine infection and quicker return to ovulation.