As of 6am this morning, there were still 5 cows yet to calve. Another one was born on my shift on Thursday morning, a really cute red Hereford bull calf. The student named him Duke. He came out weighing 92 pounds--that's a big calf.
One of the many interesting things I've learned during this project is how wide the range is for normal calving. The entire process can take five minutes or two hours (the average duration is one hour). The water sac usually comes first but it might follow the calf. The mother might do the entire thing laying down, she might calve standing up. Some cows give you lots of warning signs that they are in early labor: standing at the back of the pen, or even standing at all (the cows are usually laying down sleeping during my shift), switching their tail back and forth, lifting the head of the tail where it attaches to the spine, arching their back. They will stop ruminating. Some cows become somewhat anxious, repeatedly lying down and standing up, not able to settle. You can see them having contractions once labor begins but this is not very visible in the early stages. And when the calf is moving through the birth canal, the cows will relax their pelvic ligaments, causing their entire pelvis to rotate so that the opening that the calf passes through is more perpendicular to their path and less oblique, which makes their hip bones suddenly stick way up. Sometimes they even look "less" pregnant, a sign the baby is moving into the birth canal. But some cows give you absolutely no warning of any kind. We've had at least three calves born in which people were standing around IN THE BARN when they heard a whoosh of fluid then a plop and there was a calf on the ground. They had no idea at all that the cow was in labor.
Cows that have a snack on remnants of the evening feed ration are probably not going to calve in the next few hours. In fact, one of the first things I do when I arrive at the barn for my shift is go down the aisle and sweep the scattered alfalfa hay remnants back up to the pens. Cows that don't come up for this are the ones I watch most closely. It's proven a reliable test for weeks now--I've in fact predicted which cow was going to calve next probably half a dozen times based on this and my other observations.
I have a bit of an advantage over the students and other supervisors. I'm the only person who is at the barn every single day at the same time. The PI of the project is at the barn every day but she isn't there at the same time. Cows have routines just like we do, and by observing them at the same time, I am able to notice even small changes in behavior. However, it's taken me all of these five weeks to compile a relatively complete catalog of possible early labor signs because no cow exhibits all of them.
Getting the blood samples has also involved an evolution of process. When I had to draw blood on the calves back at the start of the project, I would often close my eyes when feeling the vein. Closing my eyes narrowed my focus and I would visualize the vein in 3D, its diameter and orientation, whether it seemed "rolly". Sometimes the vein will roll a bit under the needle and you will nick the vein instead of hitting it in the middle. I'd release the pressure to let it deflate then hold it off again two or three times to make sure I was going for the vein and not some ligament in the neck or, dog forbid, the artery. I might hold off on both sides before choosing the side I preferred, although to be honest, as I am left-handed, I prefer to bleed from the calf's left side, which is on my right as it faces me. Even so, if the vein is better on the calf's right, I'll go for that one. The process was somewhat theatrical, to be sure. I'd usually verbalize continuously, I feel it here, this one looks good, etc. It's an oddly intimate thing to do--I'm on my knees in front of the calf (I prefer to do this in a pile of grass hay if possible to provide a cushion for everyone) while the student is kneeling over the calf's shoulders, holding its head firmly but not too tightly against them. The calf might have its front feet folded under or straight out in front, and its hind feet turned to the side or tucked under. Anyway, what I'm getting at is that I can't see the face of the holder. I am sure there were many eye rolls at my dramatic performance but I don't care. It worked for me, forced me to take my time, be patient, know exactly where that needle had to go before I ever uncapped it. And I have become pretty good at getting blood from jugular veins of calves. It usually takes longer to get the calf settled on the ground that it does for me to get the sample.
So to close, I have a small brag. One of the supervisors called me to the barn for a blood draw (he remains unwilling to even attempt one). When I showed up, the PI was there too. She was surprised to see me but I told her quietly that I had been called in. She said, okay, since you're here, we need to get blood from that cow too. Into the chute the cow went, halter put on her head, head tied off to the side. Jean handed me the tubes and the cuvette (we have to fill three tubes from the mothers), and while she and I were jibber-jabbering about something, I proceeded to do the blood draw. No drama, no problems, nothing but three tubes full of purple venous blood. As I was withdrawing the needle, I suddenly realized that I had done the procedure entirely on auto-pilot. Jean realized this at the same time, and said, well, it looks like you can draw blood from just about anything now. Wow, that made me feel really good that she not only recognized my accomplishment but that she let me know it.
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