Friday, April 15, 2011

Sheep school

Yesterday was one of the twice-a-year days when the Womerlippi Farmers host first year students from Unity College's Captive Wildlife Care and Education degree program for training in animal handling using sheep.

The sheep need the handling, while the students need the experience, so this is a good trade for all of us. The sheep, for their part, get all their shots, their hoofs trimmed, their dung tags removed, and so on, the 3,000 mile service.

While the students get what we believe is exceptionally good experience, handling large, balky and even hostile animals.

Timing is everything, and in this case the timing was great for the students, but not so good for the sheep. We had hoped to get the students in before lambing, but as usual the stupidity of the college schedule defeated our plans.

If I ever happen to meet the absolute moron it was that decided one fine day that something useful to humanity could be learned in a fifty minute class, and then filled up students', and faculty members' days with these classes, carefully spaced apart so as to allow only a minimal amount of time for practicing difficult things or concentrating hard on tricky jobs, or, well, just plain thinking about things, well, I'll have something to say to that person.

My idea of a good class is at least a half a day, maybe more, of practical application solidly linked to theory.

We had two hours and ten minutes, and made the best of things. I had everything set up ahead of time, and we worked our way though the animals as methodically as we could in the time available.

We started with a good scrubbing of student's welly boots in disinfectant, to remove or kill any disease organisms from other farms, or the zoos and wildlife centers that these students regularly visit.

We then had a good briefing, in which their major professor, Cheryl Frederick and I emphasized that what we were about to do would be hard work, dirty, unpleasant, risky to the animals, and based on hard science. This is an important moment because the students in this particular program sometimes arrive with what I call the "Animal Planet" mentality, which is something along the lines that cute, fuzzy animals are entertaining, and that because I'm in this degree program and not, say, straight biology, I don't have to take the hard biology classes that are required, or at least, I don't have to take them seriously.

These students, along with the Marine Biology students, I'm sorry to say, routinely get the worst grades in genetics, cell biology, and similar "hard" courses, as well as in math. They often see these more abstract courses as unpleasant and unnecessary.

(This is particularly frustrating to Aimee, who often comes home quite angry about it.)

Whereas in reality, all serious modern animal care and medicine is applied biology, and if students don't pay attention in genetics or cell biology, they may not fully understand procedures, and, in their future careers, at best they'll have to resort to the use of rote systems and depend on others to actually work out systems of care, being handicapped in doing it themselves by their ignorance of the biological basis of care.

At worst, they'll kill animals.

Which we nearly did yesterday, more of which later.

So the students got a five minute briefing in which we connected the systems of care they would learn to the biology in classes, emphasized the hard work and need for grit and guts in handling the animals. Seeing a few glazed eyes and minds already wandering (which is normal for first years, but not good, a sign of poor high-schooling and short attention spans and the like), we made eye contact, and I made sure they were paying attention with a mild but gruff warning.

Once we had their full attention and minds on task, we got stuck in.

With only two hours to go, everything had to be set up ahead of time. Earlier I had penned the sheep into the back of the barn, where they spend the winter. This is a safe place for them and they were quiet and settled. I stepped in and started handing out lambs, one by one. Each lamb got a subcutaneous injection of tetanus vaccine. The students gave the shots. They had earlier been told how to do it, and then we showed them how, with the first lamb; after that each student got to inject a lamb, and later, the ewes.

The best place to inject a sheep with tetanus vaccine or any other subcutaneous medicine is in one of the four "armpits," the area of bald, loose skin on the inside where the limb meets the body. It's easy to pinch up a flap of this skin, insert the needle, and inject the medicine right under the skin layer, avoiding muscle tissue and blood vessels.

The students had been warned that as soon as the ewes were separated from the lambs all kinds of noise would break out, making it hard to concentrate, and this duly occurred as babies were separated from mothers.

Each lamb was then returned to the lambing pen, still isolated from the mothers.

The next job was to work on the mothers themselves, and just naturally the angriest mothers presented themselves first at the gate of their pen, very hostile, and bleating for their babies. It was a simple matter to let them out one at a time, catch them, and take them outside into the sun for their routine work.

A romantic notion of sheep handling might have left the lambs with the mothers, but this might have resulted in lambs getting crushed while mothers were caught.

Again, students need to learn to let go of soppy sentiments and plan out systems of handling and care that are best for the animals and realistic of the difficulties involved.

Taking the angriest mothers first this way was good, because that meant we got all the most difficult sheep done first. And of course, first of all was Nellie, then Tillie, then Molly, then Poppy.

Tillie is probably our Number One best mother, and most experienced. But Nellie is the most caring mother we have. Molly is an easy third, and Poppy is just learning, so the order in which the angry sheep appeared at the gate was just naturally the exact order of their ranking of motherly ethic.

Our Corriedale-Romney cross sheep are big, solid and very strong, no pushovers. A Corriedale ewe is just naturally one of the finest and feistiest mothers in the animal world. All the mothers wanted very badly to be back with their babies.

It was no mean feat to catch each one, give her a shot, trim hooves and dung tags.

Once fixed up, the mothers could then go back to the paddock,, and each set of lambs could then be brought out, given five cubic centimeters of vitamin paste (containing selenium for protection against white muscle disease), and then released to the mothers.

The noise level slowly dropped.

A moment of quiet drama ensued when a student accidentally nicked one of Tillie's arteries with the needle while giving the tetanus shot. Bright red blood leaked out of the wound under the skin, making a bulge.

This might easily have caused Tillie's death. What happens is that the slug of liquid medicine in the blood vessel becomes in effect an embolism, and if it enters the blood vessels of the heart, can stop that organ beating.

This is called thrombosis, and humans get it too, when we have a "stroke."

Luckily it was one of Tillie's arteries that was hit, not a vein, based on the bright red color of the blood that we saw.

Arterial bleeding from a puncture wound will usually stop, so I wasn't worried about Tillie bleeding to death. But I was worried about a thrombosis.

But again we were lucky in that it was an artery and not a vein, and so any medicine that made it into the vessel would have had to have been pushed through capillaries and the tissue they serve, and so necessarily dispersed before making it to a vein, then to the heart. In addition, the pressure in an artery is greater, so it's harder to push the medicine in to the blood vessel. More likely the arterial pressure pushed the medicine out, and we had instead a bulge of blood mixed with medicine under the skin, which would go away eventually, and the medicine would still be effective.

This accident was partly my fault for not mentioning as positively as I should have that it was important to get the medicine just under the skin, and not in a muscle or blood vessel.

I showed the students how to do it, but I didn't tell them this last part.

And not all students were perhaps paying full attention to the demonstration.

Again, if we could only have them for longer periods, so things weren't so rushed, this kind of mistake would be harder to make.

Once we realized what we had done, we just stopped work, let Tillie go, found her lambs and gave them back to her, and then just watched her for a few minutes to make sure she didn't keel over.

And she didn't.

Phew. Good lesson for students, better lesson for instructor.

One way to be sure that you haven't nicked a blood cell is to pull back on the syringe after the needle is inserted but before depressing the plunger, but this is usually not needed for a simple subcutaneous shot like this one.

Next time I'll be even more gruff about getting everyone's attention, and make sure each student sees the demonstration before doing the job themselves. Also, when I was training to be a military medic we practiced on skin/muscle analogs -- loose skinned oranges, actually, but I'm sure we can buy something bespoke from a hospital supply warehouse.

The student that gave the faulty shot was very surprised when we assigned her to give the very next shot. But you have to get right back on the horse that threw you while the adrenaline is still in your system. If you don't fear may take over, and you may never succeed at learning the job.

She did a much better job of the next injection. Well done.

After a while all the mothers were happily reunited with their lambs and the mayhem quieted. The remaining sheep got quite a bit of attention, except for Jewel, the second oldest ewe, who characteristically fought us all off, and went into the paddock without treatment.

This may not be such a bad thing, as it may soon be time to take her to the butchers.

I perhaps should have mentioned this too to the students, but an old retired ewe like Jewel will die eventually, either as her teeth wear out, or as she gets one or more of the hundreds of dread diseases of sheep. Jewel herself took ill last year, to Listeriosis or "circling diesease" and nearly died.

It's much better for them to die quickly in the slaughterhouse and for us to get the meat (which I usually have ground up for shepherds pie and sausage), than it is to die of starvation from worn-out teeth, or from some dread disease.

Cheryl and her academic partner in this program, Sarah Cunningham, make sure to prepare students for this kind of eventuality. The very first lecture the students get is on death, an immediate inoculation against the "Animal Planet" mentality.

And the first (lesson) shall be the last (lesson).


Melissa said...

It was so nice of you to let us come to you and your wife's farm. I enjoyed helping out, even though I was slightly nervous about giving a shot. My fear soon passed as I listened and watched you tell and show how it was done. This was defiantly an experience I will never forget.

Mick said...

We aim to please, and to serve the mission of getting you guys trained up to be the best animal caregivers you can be.

Plus, truth be told, it's a lot easier to get the job done when there are that many people to help out. We've come to rely on the help.