Ew, That's Gross! Hold On, Let Me Get A Picture!

How do you know when you are working with animal science students? When confronted with slimy body parts or stinky, sticky body fluids, their first response is just like yours: ew, that's gross. But their next response is to touch it, pick it up, turn it over, and of course take a picture.

Yep, a bovine placenta. It is a sac that surrounds the calf. The red blobs are on the outside surface. They link to similarly sized blobs on the cow's uterus (caruncles) and are the connection points between cow and calf. This strange arrangement means that cows don't transmit certain things to their fetuses in utero, but only through colostrum after birth. This cow had given birth just a couple of hours before. The stress of moving through the chute caused her to drop her placenta pretty quickly. Usually they are dropped in the pens so are covered with bedding and poop. This one was nice and clean, well, relatively so, and was very photogenic.

Don't even get me started on the evolution of feces in newborn calves or the various states of vulval prolapse in pregnant cows.

We went 9 days at the barn without a birth. Some of these last 17 cows aren't predicted to be due until next week, some are past due. That is, if you actually believe the predicted birth dates. I made a graph of predicted versus actual to date: two cows birthed on their predicted date, half a dozen birthed after their predicted date, and the rest birthed up to two weeks earlier than their predicted date. In sum, predicted birth dates were not terribly useful.

Nine days of nothing except really nice spring weather, and suddenly in about 12 hours we had 4 calves on the ground. I watched another one being born this morning, my sixth, I think. 

Newborn calves are pretty fun to watch. As mother licks them dry, they fluff up and warm up. Eventually they begin to attempt to stand, usually within 15 minutes of birth. This is the most amusing part of the process because their legs and their brain are not communicating too well and each of their legs can end up going in a different direction. I've seen some calves do spectacular face plants and somersaults. But most of them are standing within another 15 minutes, wobbly to be sure but standing. They will often start to frisk and gambol about the pen within a couple of hours. Happy to be on this earth.

Cow licking the calf stimulates hormones and endorphins in both of them. Calf nursing stimulates hormones in cow that assist with release of the placenta and increased milk production. These are called neuroendocrine reflexes: a physical sensor (touch) generates a response in the hypothalamus in the brain which then sends signals to hormone-releasing tissues. And there are pheromones present, at least for a few minutes after birth. But I've been wondering about another thing the cows do: they moo very loudly at an oddly low frequency right at their calf's head, over and over, especially in the first few hours. It is not a normal cow vocalization and seems to be restricted to cows with newborn calves. I wonder if the frequency of the sound is also creating some neuroendocrine reflex.

The supervisor on the shift before mine called me at midnight--I was deep asleep. But she couldn't get a blood sample from a newborn and it is fairly critical to the research study that the zero hour blood sample be drawn before the calves begin to nurse. I managed to stumble in by 1am, an hour before I was supposed to be there, and got the calf weighed and blood drawn in 15 minutes (with the help of two students). Thankfully, that calf hadn't started nursing yet. Sometimes it takes cow and calf a few hours to get it together. With all of the blood draws and cow/calf management this morning, I wasn't able to sit down until 4:30am. Whew!

Getting a colostrum sample from a beef cow. They can still kick even when in the squeeze chute so you have to be careful.