Over the weekend we had a new experience – drawing blood from tails for pregnancy tests. Dairy Farmers of America (DFA) is offering a new blood pregnancy test, and it’s really convenient. The lab sent us supplies to get the samples through FedEx, and we just send them in with our milk hauler, who comes every other day to get our milk anyway.
Until this year, we were determining pregnancies the old fashioned way…we waited. If a cow didn’t show signs of heat after her most recent breeding, we waited until her calf was big enough to “bump it” or feel it from the outside. You can first bump a calf at about 6 months, so it was a pretty long wait to be sure. Many farmers palpate, or preg check, their cows, but this isn’t something we had been doing. A veterinarian can identify a pregnancy by palpating at 60-90 days, but David didn’t feel comfortable until 4 or 5 months doing it himself, and we don’t have a vet come to the farm regularly. We do have a vet that we call for emergencies and who supplies us with needed medications, but David does the majority of our veterinary work.
These new blood tests claim to determine pregnancies accurately at 28 days – that’s a huge improvement from 6 months. We drew blood from every animal that we had bred between Jan 1st and Feb 11th that hadn’t shown a heat since her breeding; the total was 26 cows and 3 heifers. We sent the blood samples with our milk hauler Monday morning, and we got the results emailed to us this afternoon.
Out of 29 tested, 25 were bred!!
One of those that wasn’t bred actually showed signs of heat Monday and has already been rebred. There were several other animals that had been rebred prior to testing, and some of those tested had been bred twice in that time frame, so 25/29 isn’t our overall conception rate. We added everything up tonight and looked at several angles.
Our overall conception rate for that 6 weeks was 25 for 40, or about 63%. Below is a look at pregnancies/attempts for each bull that we use:
The jist: we’re going to have 25 calves in a 6 week span this fall, and around here that’s quite a few! Can’t wait!