Hypocalcemia, immunosuppresson, negative energy balance — they’re all part of the early-lactation experience.
But what about trace mineral deficiency? Do early-lactation cows experience this problem, as well? There isn’t much research on this, according to Rodrigo Bicalho, assistant professor of dairy production medicine at Cornell University. His hypothesis is yes, cows are trace-mineral deficient in early lactation, particularly the first seven days postpartum. So, he set out to prove this hypothesis in a research experiment with more than 1,500 Holstein cows from four commercial dairy farms in upstate New York.
Treatment cows received three shots of a commercial trace mineral supplement. Injections were given at dryoff, 15 days pre-partum and 35 days post-partum. This was on top of the fact the farms were already providing trace minerals through the feed. Control cows didn’t receive any injections. It turned out there were some significant differences. Treatment cows had a significantly lower incidence of clinical mastitis, clinical endometritis and stillbirths than the control cows. And, “the older cows had a bigger benefit of treatment compared to the younger cows,” Bicalho told those attending the Dairy Cattle Reproduction Council meeting in Sacramento, Calif., in early November.
He also pointed out that injections are a supplemental strategy and should not be considered a replacement for trace minerals in the feed. “This should be considered on top of a good feeding strategy,” Bicalho said.
With the injections, treatment cows received trace minerals in excess of National Research Council recommendations.
The research is now under review for publication in the Journal of Dairy Science.