PROGESTERONE MONITORING IN ROBOTS

Sometimes reproductive management can be a guessing game. “I guess she’s pregnant, but I thought I saw her in standing heat.” “I guess she’s on the ‘high activity’ list, but I just inseminated her last week.” “I guess she should have been in heat by now, but I haven’t seen anything.” A progesterone monitoring system in your robots can take away some of that guesswork. DeLaval’s V310* robot automatically collects regularly scheduled milk samples, and tests them for progesterone. Success depends on understanding progesterone, understanding the system, and adjusting your program to use the information.

What is progesterone?

Progesterone is a hormone that is produced on a cow’s ovary by the Corpus Luteum (CL). If you have heard the vet say that your cow has a CL, that cow has elevated progesterone. If you have ever given a cow prostaglandin, you have made the CL go away and her progesterone level went down. A cow will have high progesterone when she is between heats or when she is pregnant. The graph shows progesterone rising and falling through 3 normal cycles. The green line is progesterone gradually increasing to a peak, and falling rapidly before the cow comes into heat. The orange triangles indicate that progesterone has dropped, she is coming into heat, and could be inseminated soon. If progesterone stays high after a cow is inseminated, she is likely to be pregnant.

Understanding the system

To minimize cost, the frequency of sampling is based on where the cow is expected to be in her cycle. Progesterone increases slowly after a cow has been in heat, so the system waits several days for the first test. Testing becomes more frequent as progesterone increases. Once progesterone starts to drop, every milking will be sampled to predict the time to breed. Testing will stop when a cow is confirmed pregnant. If hormone injections initiate a progesterone drop at a point when sampling is less frequent, the system might miss that heat. Hormone use should be limited to treatment of cows that are not cycling normally.

Adjusting your program

Progesterone monitoring shows whether cows are cycling normally. Progesterone will not increase for cows that do not cycle after calving, and those cows can be identified and treated. Normally cycling cows can be inseminated according to progesterone. Visual observation or activity monitoring may help to pin point the best time to inseminate. Synchronization programs should not be used on cows that are cycling normally. Cystic cows can be identified and treated because progesterone will either stay high or low for an extended time. If progesterone stays high for an extended period of time after insemination, the system will suggest that the cow is likely to be pregnant and prompt to enter a pregnancy diagnosis in the herd records. Some herds have eliminated palpation or ultrasound for pregnancy diagnosis.

Does it fit your farm?

Progesterone monitoring can facilitate targeted reproductive management and eliminate guesswork for individual cows. It can help to minimize the amount of time spent in the pen, handling the cows, and disrupting cow flow. The system does require management and it is important to identify the person who will take ownership before the system goes online. Understand the limitations of your present reproductive management system and determine whether progesterone monitoring will address those limitations. Cow Corner can help with an unbiased evaluation.

*V310 is a trademark of DeLaval. Cow Corner is not affiliated with DeLaval and does not endorse the V310.