Use voluntary waiting period data to set cows up for success

This article originally appeared in Progressive Dairy September 5, 2024.

At a glance: Gathering and analyzing data during the voluntary waiting period can help you find fertility and health challenges early, allowing for timely interventions and greater cow performance.

By Steven Pavelski , Nedap Large Herd Application Expert

A dairy cow’s voluntary waiting period (VWP), the time after calving until breeding, is a flurry of internal activity. During the transition from pregnancy, cows are challenged with a slew of physiological processes, including metabolic changes, an increase in energy demand, rebalancing of their immune system and hormonal stabilization.

Eventually, this results in the resumption of cyclicity, an important fertility indicator for the next breeding. Perhaps the VWP should be considered a preparation period.

Historically, the VWP for many farms has been about 60 days. However, the length of your dairy’s VWP does not necessarily matter as long as it is consistent and fits within your management parameters. And cow performance remains optimal.

The most profitable VWP has been found to be less than 70 days, but it is still profitable as long as it is greater than 42 days. It is most important you abide by it and track what is happening with cows during this timeframe.

Monitor cows during the VWP

Even though reproductive protocols are on hold during the VWP, progressive dairies monitor estrous during this time to ensure a cow’s cycle returns to normal.

Simply waiting until the VWP expires before tracking estrous activity often results in missed opportunities for timely interventions to correct fertility challenges before they result in extended lactations, reduced pregnancy rates or culling due to reproductive failure.

Routinely monitoring for signs of heat during the VWP has many benefits. Research shows:

• Estrous expression from day seven until 60 days postpartum is associated with the length of estrous and estrous intensity at first artificial insemination (AI).
• Cows showing no heat in the first 60 days after calving have a lower pregnancy per AI at first service (42.5%) than cows showing one heat (50.9%) or two heats (55.4%) during the VWP.

Another study indicates cycling before the end of the VWP is also valuable for herds following timed AI protocols. Data shows that for cows enrolled in timed AI, those with no heat activity alert (38.8%) resulted in lower pregnancy per AI compared with cows with low (54.2%) or high activity increase (61.8%).

Cows that show one or two heats in the first 60 days also need 30 fewer days to become pregnant.

Peek under the hood

Understanding the data during this time is essential because the VWP is a period of vulnerability for cows. About 75% of metabolic diseases and reproductive challenges occur in the three weeks after calving.

The underlying cause may be:

• Nutrition (negative energy balance, vitamin or mineral deficiency)
• Body condition (too low or too high)
• Diseases (mastitis, metritis, ketosis or other)
• Management factors
• Hormonal imbalances

Regardless of the source, these factors often have lingering effects beyond the VWP.

Knowing what you cannot see goes a long way toward preventing and overcoming these issues. Actionable, accurate data about a cow’s activities and return to cyclicity during the VWP offers you important insight into future fertility and performance.

Put actionable data to work

Accurate individual cow data allows farmers to detect when the animal is in heat and how intense the heat event is, beginning during the VWP. It also eliminates the need for manual heat detection, freeing up employees for other tasks.

Plus, fewer days open equals higher milk production per cow per year and lower AI costs. Assuming the cost of an open day (outside of the VWP) is $4, reducing the number of days open by five days equals $20 per cow. For a herd of 1,000 cows, the cost reduction would be $20,000.

Use VWP estrous expression information to identify cows with irregular cycles or non-cyclic cows. Include them on the work list for further examination before breeding protocols begin.

With proper intervention, nutrition or management adjustments cows can return to cyclicity, increasing the likelihood of positive pregnancy outcomes following the VWP.

Additionally, data can be used as the basis for selective, targeted breeding protocols. For example, cows with the best genetic potential showing multiple heats can be selected for insemination with sexed semen, since these animals have a significantly higher conception rate than those not cycling regularly.

Ultimately, actionable data can be used to fine-tune your herd’s reproductive performance and overall efficiency. Stop waiting to see how cows come through the VWP and start acting to improve outcomes.

Visit nedap-livestockmanagement.com to learn more.