Is my herd's pregnancy rate keeping up?
The beginning of a new year is a good time to reflect on the past year’s performance and commit to doing better in the upcoming year. Am I keeping up with my peers? One area of management that has greatly improved over the past several years is pregnancy rate. A few years ago a 20% pregnancy rate was something to be admired. I used DairyMetrics to generate an annual pregnancy rate graph of Minnesota DHI herds over the past 5 years (Figure 1). DairyMetrics is a benchmarking system available through Dairy Records Management Systems (DRMS). This site allows benchmarking of herds and even allows users to set parameters against which to benchmark. It shows that the average pregnancy rate across Minnesota herds is currently about 18.5%. This is up from under 15% just 5 years ago.
Figure 1. Minnesota DHI herds annual pregnancy rate.
Table 1 looks closer at different parameters that could be affecting pregnancy rate. Not surprisingly, herds with higher pregnancy rates average lower days open. Even though the voluntary waiting period is similar for all groups at 60 days, herds above a 20% pregnancy rate inseminate cows an average of about 2 weeks earlier than average herds. These higher pregnancy rate herds also have higher submission rates and conception rates.
|Item||Average||>20% pg rate||>25% pg rate|
|Rolling herd avg (lbs)||22,770||24,803||25,617|
|Avg pg rate (%)||18.4||25||28.8|
|Days to first service||90||76||73|
|Submission rate (%)||46||59||64|
|Conception rate (%)||38||42||43|
Economics of reproductive performance
There are many ways that improved reproductive performance improves profitability including:
- Decreased average days in milk for the lactating herd
- Decreased culling of productive cows because of reproductive failure
- More calves born to be sold or raised as replacements
- Improved genetic gain
- Less variability in lactation and dry period length
Dr. Victor Cabrera (University of Wisconsin) developed a dairy reproductive economic analysis tool to examine the economic impact of improved reproduction. Using average herd parameters, increasing the pregnancy rate from 16 to 22% results in an increased annual profit of $104 per cow. There is a diminishing return as pregnancy rates increase so increasing the pregnancy rate from 22 to 26% only results in about $42 increased profit per cow annually. Even though this is lower, it is worth achieving higher pregnancy rates.
How to achieve high pregnancy rates
It is not easy achieving high pregnancy rates, but herds that achieve these high pregnancy rates also do not use any magic. These herds make excellent reproduction a priority and develop a systematic plan to make it happen.
Some keys to have consistently high pregnancy rates include:
- Transition cow programs that minimize risk of disease after calving
- Nutrition programs that minimize cow body condition losses; cows begin cycling shortly after calving
- Systems that get cows inseminated rapidly after the end of the voluntary waiting period
- Systems that allow rapid identification and re-insemination of open cows
- A well-designed vaccination program
There are currently many tools available to assist with these goals. Newer, well-designed synchronization programs can result in higher conception rates. Many farms have had success using activity monitoring systems to help identify cows in estrus. Other farms use low tech, but proven successful tools, like tail paint. Herds that are achieving the highest pregnancy rates are often using a combination of tools. The key is to work with your veterinarian and reproductive advisors to develop a system that works on your farm. Then use records and adjust your program accordingly.