Twin Calves

This time of year is so busy for us. It’s calf season! We have a fine bunch of mamas this year. Anyone who has cows knows a couple of things about mama cows. One, they like to hide their babies from us. Two, they are extremely protective of their babies with some mamas becoming outright homicidal when you get too close to their babies. This time of year can be stressful, as we try hard to keep track of who has had their babies and get them tagged while also trying to get eyes on the calves every day.

Seeing the calves every day can sometimes be easier said than done. We do our best, but we currently have the cows in a wooded field. Mamas who like to play hide and seek with their babies will pull their babies off into the wooded area to hide them from us. So far, we have been able to put eyes on each calf at least once per day, and we are checking them twice daily.

Yesterday morning, B went to check cows and found that one of our mamas had twins! She was missing when we checked cows the night before, and he found her yesterday morning with her two babies. Immediately he knew that she was not producing enough milk to support both babies. With the help of a friend, he was able to catch one of the calves and brought her to the house to bottle feed. The mama will produce enough milk for the other calf. We don’t have twins on the farm often. Here are some interesting twin facts for you:

In beef breeds, twins occur about 1% of the time. There is a higher rate of twins in dairy breeds.

In other farm animals (sheep and goats) it is extremely common to have twins. In cows, however, having twins can be a bad thing. Having twins is hard on the body, and a cows body is only made to have one baby at a time. Having twins means a higher rate of abortions (miscarriages in cows are called abortions) both in early pregnancy and in late term pregnancy.

Cows that are carrying twins have problems during delivery more commonly than single calf pregnancies. These mamas will generally need help during delivery. Cows that are carrying twins will more frequently go in to preterm labor, and the calves aren’t mature enough to survive.

It is pretty rare to have identical twin calves. In twin calves, you are 25% likely to have two bull calves, 25% likely to have two heifer calves, and 50% likely to have one bull and one heifer. 90% of the cases where you have one bull and one heifer calf, the heifer is infertile.

An infertile female twin is called a Freemartin. When a female and male calf share a uterus, the male hormones will cross through the blood supply to the female calf and that will cause abnormalities in her reproductive organs, making it nearly impossible for her to have babies. There are ways to check if she will be infertile, including a blood test. Typically a Freemartin cow would be raised for beef.

Twins are genetic. Twin heifers are more likely to have twins.

When we have twins on the farm, we always pull one calf off of the mama in order to ensure that each calf gets his best chance. In twins, it is common for one calf to be a lot stronger. This will mean that the stronger calf will get all the mama’s milk, and the weaker calf will likely starve to death. The alternative is that each calf will get half the milk produced by mama, but it will not be enough for them. Mamas to twins rarely produce enough milk to support two babies.

We look forward to seeing our babies grown this fall and winter. Calf season is tough, and can be stressful, but it is worth it.