We’re just finishing up the breeding season on our operation, utilizing artificial insemination (AI) and estrus synchronization (ES) to get heifers and cows bred. We’ll then turn out our bulls for summer clean-up. Over the years, we’ve tried a lot of different protocols, with varying degrees of success.
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Of course, hindsight is 20-20, and we’ve made plenty of mistakes along the way. Looking back, we can see why certain protocols didn’t work, and it just goes to show that each operation is unique and has its own set of challenges when trying to synchronize females for breeding.
For example, we’ve used the melengestrol acetate (MGA) protocol, which is a feed additive that is inexpensive and promises to work for both cycling and anestrus cows. Following all of the directions, we ended up with a bust, and very few heifers coming into heat after the protocol was complete. We ended up heat detecting and AIing the heifers that way. We suspect we used the protocol before those heifers had reached pubertal maturity, and that’s why we had issues.
We’ve had mixed luck with Controlled Intra-vaginal Drug Release (CIDR) protocols, as well. It worked great some years, while at other times, such as a few years back during a particularly wet and muddy spring, performance fell off. We surmised that the weather and muck were factors in our lower conception rates.
In choosing an ES protocol, there are many factors to consider, including the percentage of heifers and cows detected in heat and inseminated on time; the fertility level of those cows; body condition score of the cows; and the semen quality. Additionally, things like the cost, labor required, facilities available and experience will determine which ES protocols should be used.
No matter which protocol a rancher chooses, there are definite benefits to synchronization, for both purebred and commercial operations. Brent Plugg, University of Nebraska Extension agent, says that “no matter when you calve, controlling the breeding and the subsequent calving season has many benefits.”
He lists four benefits in a recent Ohio State University (OSU) Extension Beef Team newsletter.
1. “A shortened calving season provides producers a better opportunity to offer improved management and observation of the cow herd, which should result in fewer losses at calving,” he says.
2. “Shortened calving periods also facilitate improvements in herd health and management, such as uniformity in timing of vaccinations and routine management practices resulting in decreased labor requirements,” he adds.
3. Plugg explains, “Another benefit is that cow nutrition can be improved by grouping cows according to stage of gestation and feeding each group accordingly.”
4. Finally, he says, “An additional benefit is that the calf crop will be more uniform in age and size which can lead to an advantage in the market place.”
He explains in more detail the benefits of estrus synchronization, tips for success and resources to assist ranchers in choosing the best protocols here.
Which ES programs have you had the most success with? Which ones haven’t worked? Share your experiences in the comments section below.
The opinions of Amanda Radke are not necessarily those of Beefmagazine.com or the Penton Farm Progress Group.
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