PAP Testing

Last week, my favorite vet in the world came out to PAP test some of our cattle. I took these pictures last year, because the manual chute makes Wacey cry, so if you've already seen these, I do apologize.

PAP testing is to determine an idea of survivability at higher altitudes, because not all cattle are well-adapted to the rigors of lower oxygen availability and will die if left too high. This gives us an idea of cattle who are predisposed to become ill, so we can sell them. Sometimes we take them to the sale barn, and sometimes we sell them to ranches at lower altitudes where the animals should do just fine.

The vet who does our PAP testing (and who also did the PAP testing for the ranch we worked for in Montana, which is where I first met him) is Dr. Holt. He's a pioneer in his field, so we're very lucky that he is able to come out the the ranch. I can't say enough good things about him! He's so smart it boggles your mind, and is also the coolest vet I've ever met. Dr. Holt is an excellent teacher, and always loves to tell you and show you what he's doing so you can learn. He's full of tips and facts about every animal species ever, and is so enthusiastic it's contagious. He's a professor at CSU (where Bert met him) and he makes me want to go back to college--I would just follow him around all the time with a notepad if I could.

Maybe I should ask.

Anyways. PAP testing. The way the test is conducted is by inserting a catheter into the right ventricle of the animal's heart via the jugular vein. We always put a halter on the animal, because they need to stay still and the vet needs good access to their vein. Whoever gets the job of haltering needs to be pretty strong, and they usually wear lots of plastic because of all the slobber and blood.

The vet sticks a large-gauge needle into the jugular vein--you can tell because blood will spurt out. Sort of gross, but true. Then, the vet will insert a plastic tube through the needle all the way to the right ventricle of the heart, and connect it to a special machine that is hooked up to a computer thing that tells him the numbers he needs to know. That's what he's looking at in those pictures. Then, he pulls the tube out, throws it in sterile solution and does it all again on the next animal! Someone is always assigned to write down each animal's numbers, which all have a significance, but the PAP score is the one we're most concerned about--the lower the better. Our cutoff is pretty standard, about a 40, 45 at the highest.

Sometimes high-PAP animals will simply die of a heart attack, or sometimes they will die slowly, usually of brisket disease, also called pulmonary hypertension, high-altitude disease, or dropsy. We call it brisket because when they have a high PAP, the right ventricle pumps blood too slowly, and basically slows down the entire body's blood flow. Because everything isn't working efficiently, the liver and the kidneys are not able to process fluids as quickly, and so fluid (plasma) accumulates outside the organs. Because the brisket of a cow (the dangly part between their front legs) is the lowest fleshy part, sometimes the fluid will accumulate there. So, a cow with brisket will look pretty poor, and may have a big ole swollen brisket. Sometimes you can save them by taking them down to a lower elevation, but not always, which is why we do our best to relocate them before they become ill.

Obviously, we would rather not have animals dying of brisket. It's awful for them, and hurts the ranch's bottom line. So, we try to eliminate dams and sires with known PAP issues, or matings that seem to result in high-PAP calves, as well as relocate high-PAP animals before they become sick.

Now, just because an animal is high-PAP doesn't mean they'll get sick or die prematurely, but high-PAP animals are considered high-risk for developing brisket disease, so we usually do not keep animals with PAP issues on our ranch. The reverse is also true, but in those cases we just try to minimize suffering. In the spring, we will PAP test all of the replacement heifers for that exact reason, and all of the bulls we keep will be tested, too.

We test every year, because every animal is different, but also because the genetics involved with high-altitude sicknesses aren't understood very well yet. It seems that these issues can skip generations, so we try to stay on top of it.

For further reading, try this article!

Long story short, I love PAP testing--it's so interesting!--and I have grown to really appreciate good vets. They're very hard to find, and so if you have a good big-animal vet (or a small-animal vet that doesn't rob you blind and is good at their job), give them a Christmas card and some cookies, because they're so, so rare, and kind of a dying breed. We appreciate them so much!