Greener Pastures Breeding Service

How do I tell when my cow is in heat?

1). In order to determine the proper time for insemination, we need to know when the cow is first in "standing heat." The most accurate method of determining when a cow is in heat is WATCHING the animal. In order for this method to be effective, the cows need to be observed for 10 or 15 minutes at least twice each day MINIMUM. Observing your animal four times each day provides more than a 95% chance that you will acurately detect heat.

 

2). A cow's estrus cycle may range from 17 to 24 days, but average cycle lasts 21 days. Of this time, most cows are in heat for about 24-36 hours, 8-12 hours of which is "standing heat."

 

3). What is "standing heat?" In order to detect standing heat, you need to have at least one other mature bovine in the same pen as the cow you want to breed (steers usually provide the best results). As the cow begins to come into heat, you will notice an increase in activity. This usually starts with the animals resting their chins on each other's hips and gradually increases until they attempt to mount each other. "Standing heat" occurs when the cow stands still and allows the other animal to mount her. Ideally, we would like to inseminate this animal about 10-14 hours after the first time she is seen in standing heat in order to ensure the highest success rate.

 

4). What if I do not see my animal in "standing heat"? Can I still  tell when she is in heat? There are secondary signs of heat in cattle, but it is important to remember that they can be unreliable. Here are some secondary signs of heat in cattle:

•       Sudden changes in behavior including:

  •  Bellowing

  • Walking fencelines

  • Frequent urination

  • Restlessness/ Nervousness​

•       Decrease in milk production

•       Mucus discharge from vulva

•       Attempting to mount other animals

Remember that heat detection aid products (such as the ESTROTECT or KAMAR stickers) are only supplements to a solid visual heat detection program!

 

5). Still can't tell if your animal is in heat? There are other options! Some animals only display "silent heats"- so heat detection is no good. Or, you may have only one animal that doesn't display any obvious secondary signs. In these situations we recommend using a timed AI program:                                                   These programs usually provide a good success rate in situations where heat detection not possible.

What kind of success rate can I expect with AI?

Here are our average AI success rates:

Natural Heats: 85-95% success rate

Estrus Synchronization with Timed AI: 65-80% success rate

 

Do you guarantee your services?

While our success rates are typically higher than the national average (which is about 2.1-2.5 breedings per pregnancy), we cannot guarantee that each insemination will result in a pregnancy. 

AI success rates depend on a variety of factors, most of which are outside of the control of the AI technician.

Some factors affecting success rates are:

• Stage of lactation

• Body condition

• Time since last pregnancy

• Age of the animal

• Breed of the animal

• Breed of the chosen bull

• Time of year (extreme heat or cold)

• QUALITY OF HEAT DETECTION!

Why AI instead of natural service?

 More Coming Soon!