Dairy producers have a new management option for managing anestrous cows. Zoetis announced that Eazi-Breed™ CIDR® Cattle Insert now has a label indication for inducing estrous cycles in anestrous lactating dairy cows.

Anestrus is a cow’s failure to show signs of heat (estrus) or estrous cycles. Incidence of anestrus during the postpartum period can negatively influence fertility.

“Anestrous cows are difficult to detect and can be a significant problem for dairies, leading to delayed breeding, longer intervals to calving, longer days in milk and ultimately, lower profits.” said Jerry Olson, DVM, Dairy Technical Services, Zoetis. “When cows fail to cycle, it can be an expensive problem.”

Today, the prevalence of anestrous cows in U.S. dairy herds is estimated at 20% to more than 40%.1 Each additional day a cow is past her Voluntary Waiting Period could cost more than $3.00 per cow per day.2

“At a time of less than favorable milk prices, producers need to capitalize on all possible efficiencies on the dairy,” said Dr. Olson. “When cows spend more time in early lactation, they produce more milk. Managing cows for successful production requires a solid reproduction program to shorten calving intervals, which is the key to keeping cows in peak milk production.”

Eazi-Breed CIDR helps improve the effectiveness of reproduction programs by tightening estrous synchronization so groups of cows and heifers begin cycling, come into heat sooner and can be bred in a narrower window.

In a multisite field study, the efficacy and safety of Eazi-Breed CIDR was evaluated in postpartum cows at nine commercial dairies:3 Of the enrolled cows:
· 426 anestrous cows received Eazi-Breed CIDR for seven days
· 430 anestrous cows received no treatment

During a 42-day observation period, cows that received Eazi-Breed CIDR showed a 37.5% relative improvement in the rate of estrous cycling induction, a significant improvement (P < 0.0001) over controls. Additionally, of those inseminated in the Eazi-Breed CIDR group during days 1 to 21, 78.3% were inseminated on the second and third day following removal of Eazi-Breed CIDR.