Friday, February 19, 2010

Pregnancy tests

Pregnant? no!

Pregnant? Probably not.

Pregnant? Yes!

Most of my sheep are pregnant. I’m quite sure of that. But I’m not exactly sure when they are due. I know the date I planned to put the rams in with the ewes. They should begin lambing about February 23 if we actually did put the rams in with the ewes that day. But I have this little niggling feeling in the back of my mind that we were late by a day or two.

What’s a day or two? Well, two days is twelve trips out to the barn to check for new babies – at least four of those trips at night. So, it would be nice if I could remember the exact date that we put them together.

Barring that, it would be nice that we had a pregnancy test that could tell us how far along the fetuses have developed. I know there are portable ultrasound machines that University shepherds use on their big flocks. But I’ve never actually known a shepherd who used anything beside the calendar, observation, and some common sense.

145 to 156 days is the normal gestation period for sheep. So we expect lambs to be born anytime between February 23 and March 27. When I look at the flock, Cedar is the animal that looks the most obviously pregnant. Unfortunately, he has never been pregnant and he never will be. He is just fat.

Most of the ewes have barrel shaped bodies right now, not showing much fetal development, like a woman at 5 months rather than 7 months. And I have learned that barrel shaped bodies might mean the sheep are pregnant or it might mean that they have been eating like a pregnant ewe all winter but aren’t actually pregnant.

The next clue I look for is a developing udder. Older pregnant ewes definitely have udders. Those I can pick out. But the yearlings and the two year olds often don’t have much udder development until just before or even after birth. When I look at my flock as they file past me on their way to the corn feeders, I see older ewes who are definitely pregnant and young ewes who may or may not be pregnant. I won’t know about those ewes until the end of lambing.

It’s nice that winter has moderated. Without a pregnancy test, I’ll just have to walk out to the barn six or seven times a day, to see who looks pregnant, and who has lambs – the best pregnancy test of all.

No comments:

Post a Comment