Progesterone monitoring improves reproduction efficiency of herd

IXONIA, Wis. — Progesterone is a hormone that can be tracked and monitored to help dairy farmers improve the reproductive performance of their cows.

“At DeLaval, we look at many farm challenges and reproduction is certainly one of them,” said Jason French, commercial portfolio manager for automated milking systems at DeLaval North America.

“About 30% of cows’ heats are silent, so reproduction is a high reason of why cows leave the farm,” said French during a webinar.

“Progesterone is the hormone that stimulates and regulates the reproduction system, prepares the body for conception and maintains the pregnancy through lactation,” he said. “It is one of the hormones that is easier to track and monitor so we call it the gold standard in reproduction.”

DeLaval has developed the RePro system that is used with a VMS V310 robot.

“We can take the sample of milk and measure the amount of progesterone in the milk sample,” French said.

“The threshold is five nanograms of progesterone, and when it gets to that level, there is a heat alarm,” he said. “The heat alarm is the crystal ball, and in 36 to 48 hours, that cow will show physical signs of heat.”

Kyle Zweig, who operates Zweig’s Maple Acres together with his wife, Rachel, their three sons and his parents, Joe and Lisa Zweig, moved their dairy herd into a guided flow barn with a DeLaval robot in 2020.

“It is a tail-to-tail, two-row barn and when the cows come to the selection gate, the milking permission set for the cow determines whether she will go towards the robot to be milked or she is put back into the feed lane,” French explained.

“The guided flow system is really about optimizing the pounds of milk per unit, per day,” Kyle Zweig said. “And the cows’ regularity in milking to keep the range of milkings per day as close to three as possible to maintain a good lactation curve over the cow’s entire lactation.”

On Zweig’s farm, the average is 66 cows through one robot.

“Our average is 108 pounds of milk per cow, with 4.4% fat and 3.3% protein,” he said. “And the cows are currently about 154 days in milk.”

Prior to adding the DeLaval RePro system, the voluntary waiting period at the Wisconsin farm was 70 days.

“After 70 days, we would allow 90 days for breeding to natural heats and at 90 days we would start the cow on a CIDR Synch program,” Zweig said.

“Repro vet checks were conducted every two weeks, pregnancy checks were at 30 days post breeding and a follow-up recheck in the 45 to 60-day range,” he said. “We were right around a 22% pregnancy rate.”

By adding the new progesterone monitoring system, Zweig said, the entire process of reproductive management has changed at his farm.

“It is a completely different way to manage cows when you have solid daily data,” he said.

The voluntary waiting period for the cows has changed drastically.

“When you are testing and finding every heat, you can really push the voluntary waiting period back and condense the breeding days into a very tight window,” Zweig said.

The dairyman started with an 80-day voluntary waiting period, increased it to 85 days and then 90 days.

“We have now settled on 95 days as our voluntary waiting period,” Zwieg said.

“There is no more natural heat voluntary waiting period because 95% of the breedings are off of natural heat,” he said. “All the cycles we were missing to silent heats or the cows not showing any physical symptoms are non-existent.”

For the past nine months, since Zweig started using the RePro system, he has put only four cows on a CIDR Synch program.

“Every other cow was a natural heat pregnancy,” he said.

Zweig has eliminated the vet checks to palpate cows.

“Everything is done by progesterone testing,” he said. “Repro checks can be whenever we want and as often as we want because the progesterone levels will give us the information we need.”

Now the pregnancy rate for the dairy herd has increased to 47%.

“We know that 48 hours after a drop in progesterone in the bovine species that is the point of ovulation,” Zweig said. “So, the cows are breed 48 to 60 hours after that drop below the threshold.”

In the DeLaval RePro system, dairymen can change the testing for progesterone to match their needs.

“It is set up to test cows more frequently as they move closer to their heat cycle, but you can customize that,” Zweig said.

By using this system, the dairyman said, he has learned about the inaccuracy of the relationship between physical signs of heat and ovulation.

“We have cows that are ovulating 48 hours before they are showing physical signs and cows that are ovulating 48 hours after,” he reported. “Physical signs are not as closely correlated to the timing of ovulation as what the industry currently thinks.”

“We think we know who problem cows are, but we were breeding them two days away from where they should have been bred and that’s why they were performing poorly reproductively,” he said.

Now that Zweig uses progesterone testing, the service rate statistic is no use to his operation.

“I know every heat, every time, so the only time I don’t breed a cow is when I choose not to,” he said.

Scheduled herd checks have been replaced by sporadic checks of the data provided by the RePro system.

“You know what is going on inside the cows all the time and you can make the correct interventions at the correct critical moments,” Zweig said. “You can be confident that every animal is cycling at any time during that 95 to 150 days in milk.”

“Progesterone testing is the largest technical advancement since the milking robot,” he said. “We have been doing the same thing in repro management for a long time, but this has totally changed the way we manage cows.”