imagePremier 1 Supplies has started blogging, and I’ve been enjoying reading about their sheep operation. Today’s post was interesting: Premier Farm Diary: Scanning Data describing their use of ultrasound to assess conception rate and separate twin- and triplet-bearing ewes as well as cull poor producers. The folks at Premier are doing some intriguing experiments with hair sheep productivity compared to wool breeds, and low-input pasture lambing systems; trying to duplicate some of the findings at US MARC. I’m looking forward to seeing their results.

Since I have worked in medical ultrasound for many years, I was curious about some of the details of this process, and looked a few things up.

First, I wondered about the machine the person is using in the photo on Premier’s blog. It looks like fairly old technology (from the early nineties maybe?), but that’s often true of veterinary applications. Usually its only affordable to use re-purposed for-human devices long after they have become obsolete for human use. But there are a few companies who manufacture veterinary-specific devices too. Here’s a website that sells a few, and boy, they are pretty expensive!

I’ve seen inexpensive “Doppler scanners” advertised in dog magazines before, in the several-hundred-dollar price range. They don’t image, they just produce an auditory signal; but perhaps with practice, it would allow you to get an idea of how many heartbeats are present. This veterinarian’s website implies that he must be using a fairly sophisticated for-sheep application and machine, because he can estimate fetal age based on image measurements. Who knew they made fetal growth tables for lambs? 😀

I enjoyed stumbling across this article on a professional sheep sonographer– I love how dirty the ultrasound machine in the photo has gotten! Maybe they need to manufacture them with windshield wipers! 😀 And wow, the sonographer in that article can do 2,500 scans per day-whoo, wouldn’t hospitals love it if they could bill that many human procedures in a day? I guess they’d need to get some chutes and a border collie to push the patients through that fast! 😉 And this blog mentions sheep scanning too, the poor machine has been taped back together with duct tape!

I also wondered how much it costs to pay a talented person to ultrasound sheep? In  Premier’s application it seems especially justified, where they don’t anticipate being able to tag or label lambs and ewes in the pasture lambing scenario in order to select for twinners for future years. This way, they can segregate them before lambing.  This useful fact sheet gives some of the math to justify paying for scanning (about $2/ewe), both in being able to sell the open ewes earlier and not feed them so long, and also in increased lambing survival rates, if pregnant ewes are fed most optimally for the number of fetuses they are carrying.

I wonder what is the diagnosis accuracy rate? (At the company where I used to work, some sonographers used to jokingly tell would-be parents “I  guarantee a 50% rate of accuracy when determining the sex of a baby…” :-D) I’d love to see some images of triplet and quad lambs in the womb, all entangled together! I couldn’t find much on google images in the way of decent lamb fetus images, however.

I wondered if the sheep are scanned on their bellies or if they are done intra-vaginally? The first website I mentioned above seems to imply abdominal scans; and that the sheep need to be “empty” (just like people!) to ensure that the sonographer isn’t trying to look through a full or gassy rumen. It sounds like maybe they don’t even need to shave them (to facilitate coupling of the transducer to the skin)- I think they do it in that “pocket” area where the thigh meets the abdomen, which I think is naturally bare on many mammals?

Lastly, I wonder if we have any livestock pregnancy scanning specialists in the Pacific Northwest? A quick search didn’t render any obvious results. Anyone know? What an interesting career that would be, sheep fetal sonography! I bet that technician has a few stories to tell!

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