To get into this long-term mindset for reproductive management, let’s look at three important considerations: 1) genetic progress, 2) future production, and 3) efficiency. And let’s keep in mind that reproductive management overlaps with many other management areas. There are close relationships with heifer management, milk production, feed management, and herd health.
Why would you NOT want to make genetic progress in your herd? The specific improvements you’re aiming for may be up for debate, but it only makes sense to aim high. Whether through intentional selection of good sires, or using more advanced technologies with embryos and/or genomic testing, there is plenty of opportunity to make progress.
Natural service is still used to some extent for breeding purposes on many dairy operations around the country. Though there are a number of risks to having breeding bulls around, a dairy owner has the right to decide whether or not to use them. But with a long-term mindset, how much might you be selling yourself short? Where is that bull from and what steps have been taken to make sure he is actually going to benefit the operation? Are the benefits truly outweighing the risks? It might be worth examining current versus potential genetic progress in the herd, including factors such as inbreeding. There may be reasonable justifications for using a particular natural service bull in the herd, but it’s worth making a concerted effort to avoid the “duds” and any complications they might bring to the operation.
Achieving timely conception certainly has an impact on milk production. It also impacts the rate of calves being born to use as replacements or to merchandise for additional income. But this doesn’t just pertain to lactating cows. A significant segment of the herd that often receives less attention is the young stock, both pre- and post-breeding. These heifers are the future of the dairy herd!
General recommendations from Penn State are to breed Holstein heifers when they are 13 to 15 months of age, weigh 750 to 800 pounds (or 55% of mature body weight), and measure 48 to 50 inches at the withers. Accomplishing that, they should be nearing 1300 pounds (or 85% of mature body weight) by 23 to 24 months of age and have already delivered a calf. If heifers are calving later than 23 months of age, there no benefit on milk production—just the added costs of caring for them longer. In today’s economy, it is not often profitable to have average age at first calving of 25+ months.
There are many different strategies that can be used to achieve timely first insemination postpartum. A strategy can be chosen that works well within the operation’s unique conditions, taking into account factors such as labor, equipment, and drug costs. But what about those cows that fail to conceive after the first service? There needs to be a strategy for pregnancy diagnosis and subsequent insemination that minimizes the length of time cows are open. Even in herds where really good conception rates are being achieved, having a good rebreeding strategy is important. It might be the difference between having an average days open of 125 days (good) or 160 days (not so good).
There are several options available for diagnosing pregnancy around 28 days. Having this early information helps manage for rebreeding, but there is a frustrating factor to realize. On average, 10 to 15% of pregnancies are lost between day 17 and 42 in dairy cows. This means that a small but significant percentage of cows diagnosed as pregnant on day 28 will later turn up open. Diagnosing pregnancy at a later stage of pregnancy will avoid the frustration of noticing lost pregnancies after early diagnosis but might hinder the goal of reducing the time window between inseminations.
Regardless of the approach to rebreeding, heat detection can be helpful. There is no need to wait until a synchronization protocol has been completed before rebreeding a cow. If she is exhibiting standing behavior and seems to be cycling normally, she can be bred. If workers on a dairy, regardless of their official role, are on the watch for cows in estrus, these small efforts can go a long way.
There are many benefits to implementing proven strategies for reproductive management. Just remember to be patient and think about the long-term picture. You’re in a position today to make decisions that can benefit you well into the future, even though you might not see all of the benefits immediately.
This article is a preview of what will be presented at the 2015 SW Pennsylvania Regional Dairy Day in Blairsville, PA on March 5th.