Sample Collection Day

Yesterday was day 35 of my first feeding trial. For several reasons that I won't get into here, my advisor and I decided to terminate the trial after five weeks, not six. In commercial production settings, broiler chickens would have been euthanized on day 42; that loss of a week of mostly fat production won't affect our results. We got a final weight on all the pens and remaining feed. We also selected eight birds from each of the three diets from which to collect samples.

Despite the tone of the title of this post, collecting samples from poultry feeding trials is not benign. In fact, it requires that the chickens be euthanized and cut up, with specific parts removed, weighed, and bagged for later analysis. Since the weight of the parts is normalized to the weight of the individual chicken, we got a final "live weight" on each bird and euthanized them separately, one by one. The most humane method, and in fact the method required by the university laboratory animal protocol, for euthanizing small animals (mice, rats, birds) is with CO2 gas. While the trauma isn't zero, it is much less than the animal would experience from other more, well, let's say, hands-on methods.

You can do the math--we processed 24 birds today. Thankfully, my advisor wrangled a couple of undergrads into helping us. We assigned B* the very important job of recorder: he wrote down weights of everything on prepared spreadsheets. He also helped us keep track of which bird was being worked on and which bird was in the CO2 box waiting to be processed. I started out weighing parts, putting them in ziplock bags then into a cooler filled with ice, but when the second undergrad showed up, I was promoted to the job of parts collection. My advisor took considerable time to show us all the various organs and some unusual variations that turned up in one or two of the birds. She also showed me how to quickly disassemble a whole chicken.

When I was a kid, you could still get your meat from a butcher, but those styrofoam-plated parts wrapped in shiny plastic, lined up so neatly in the supermarket, were quickly becoming the norm. In short, I've never had the opportunity to cut up an entire chicken--one that still had guts, feathers, skin. One that was still warm. One that died after I put it in a metal box and turned the valve on a gas cylinder. It was quite an experience. There is of course a method but there isn't a lot of finesse. A fair bit of hacking and cracking is involved.

It was a tiring, messy morning. A shower and a good meal were necessary before the metallic taste left my nose and throat. And to be honest, it might be a few days, maybe a week or two, before I can eat chicken again. In fact, I think this is what surprised me the most about this morning. The birds weren't pets but I have cared for them daily for weeks. They weren't individuals. Still, they were living creatures. We were all appropriately respectful (no chicken corpse dance routines or chicken head ventriloquism, for example), but there is no escaping the fact that we killed and cut up 24 chickens this morning.

On the other hand, knowing how to humanely kill and butcher an animal is a perfectly respectable and useful skill. My research has fairly direct applications to human and poultry health and welfare. It wasn't a pointless exercise, or one done with glee or pleasure.

There are pictures but I have put them below the fold. If you are squeamish, DO NOT click the "read more" link. I won't force anyone to look at the reality of broiler chicken research. 

* It feels weird, not using full names. Echoes of living and blogging in the Magic Kingdom. But there are plenty of people who have radical ideas about animal research. No need to stir the flames.

I'm removing the spleen. It's a very small organ, easy to miss in the general chaos of the GI tract.

The CO2 box is in the background. The cutting boards got really messy after four or five birds; it was necessary to clean them often. I'm removing the right thigh.

My advisor and I removing parts that L will clean in saline solution, weigh, and bag. She is almost done with her bird; I am just getting started on mine.