It is easy to measure the impact certain decisions on your dairy have to your profitability. Changing the number of cows you are milking has a direct impact to the pounds of milk produced, changes to rations have a direct impact on feed costs, and high animal health incidents directly increase the vet and drug bill, just to name a few.

Other decisions throughout your dairy are not as easily quantified, especially when it comes to the efficiency of the reproductive program. As with any area on the dairy that is monitored and evaluated, both record-keeping and data are key to making good financial and managerial decisions for your reproductive program.

Here are common matrixes for monitoring the efficiency of the reproductive program for your dairy.

1. Days open

Days open is one of the best indicators of your dairy’s current reproductive efficiency. A good goal for days open is between 90 and 110 days open. Excessive days open (greater than 110 days) can result in $2 to $5 per day of cost to the dairy.

2. 21-day pregnancy rate

The 21-day pregnancy rate (PR) goes hand-in-hand with the days open. A higher PR will mean fewer days open and a higher overall milk per day production. The sooner a cow becomes pregnant in her lactation, the more time she spends in front of the lactation curve, where production is higher.

3. Services per conception

Services per conception (SPC) also directly affects the days open. If a cow does not conceive on a breeding, she may not be bred again for 21 days or the next estrus. It is estimated that for every 0.1 point of SPC over 1.5, it will cost the dairy $1.50. While $1.50 doesn’t seem to be a large number, when you multiply that over your herd, it can add up. For example: The estimated extra cost for a 1,000-cow dairy that has a SPC of 1.9 would be $6,000 per year.

It is very important for dairies to identify problem breeders early in their lactation. Once a cow is identified, either make her a “do not breed” (DNB) or cull her. If a cow is a known problem breeder, and is not identified early, she can inflate the dairy’s SPC quickly.

4. Dry periods

A short dry period will not allow the cow the time she needs to rest and for her mammary system to regenerate, while long dry periods will result in higher feed costs without any production in return. In addition, long dry periods can result in “fat” cows that have more dystocia and breeding problems. It is estimated that for every day over 60 days of dry period, it will cost the dairy approximately $3 per day – and for every day under 40 days, it will cost $2 per day.

5. Calving interval

The calving interval is directly affected by the days open and the gestation length, and is a good indicator of past reproductive efficiency. Try not to get too caught up in managing by this number alone, as the calving interval looks at too much historical data to get a true picture on your current reproductive performance. It is still a good number to monitor, as the goal should be to keep your calving interval as close to 365 days as possible.

Don’t forget about your heifers

The reproductive efficiency for heifers is just as important as it is for cows. Remember: Heifers are the future of the herd. Using the same matrixes as the cows for SPC and PR in combination with average age of freshening and average age at first breeding, you will be able to fine-tune your heifer reproductive program:

1. Average age at freshening

Studies have shown that heifers with calving events between 23 and 25 months old have a higher lifetime milk yield and are overall more profitable when compared to heifers that calve outside of that age. With the average cost of raising heifers from birth to calving ranging between $1,200 and $2,400 per heifer, the sooner the heifer starts her lactation, the more profitable she becomes.

2. Average age at first breeding

To be successful at calving heifers between 23 and 25 months old, conception must be achieved between 14 and 16 months old. Your heifer program needs to raise heifers so they start reaching puberty between 11 and 13 months old.

Knowing what bulls to use can affect your bottom line

The overall goal of your breeding program is to keep your cows in a healthy cycle of rest time (dry period) and lactation, with a calf as close to once a year as possible. The second-most-important goal for your breeding program is to maintain your replacement dairy heifers.

Right-sizing your heifer inventory for your dairy can make a large impact on the overall profitability of your dairy. As mentioned before, the cost of raising a heifer from birth to calving can range between $1,200 and $2,400 per heifer. With a depressed market for dairy sales, there is only a small marginal chance you will be able to recover the cost of raising excess heifers.

To optimize the number of heifers being born to only those that the dairy needs, start by evaluating cows and determining which cows have the very best genetics you want to keep in the herd. Identify those cows to breed to dairy bulls. When determining how many cows to breed to dairy, remember that your heifers will be some of your best genetics, and the majority of them should all be bred to dairy as well.

The remaining cows in your herd can then be bred to a terminal sire (beef bulls). This still produces a calf every year, allowing those cows to remain in the milking herd and still stay profitable. In addition, the calf that results from the terminal breeding will generate another revenue stream, adding to your dairy’s overall profitability.

Monitor, measure and review often

Like all areas on your dairy, reproductive efficiency needs to be monitored and reviewed frequently. Small changes can have big impacts, both positive and negative, and the only way to identify them is by looking for them.

A successful reproductive program is much more than just getting your cows and heifers pregnant. Your reproductive program will affect everything on your dairy and can promote or hinder your overall profitability.