Enriching The Broiler Chicken

One of the big buzzwords in animal science these days is "enrichment." This is sort of ironic because our feeding trials are attempts to enrich poultry meat with health-positive omega-3 fatty acids, but we are talking about two different kinds of enrichment.

It's no longer sufficient to provide research animals (or zoo animals, for that matter) with clean bedding, water, and food. The researcher is also required to provide additional items in the animal's environment that will stimulate it physically or mentally. Even so, enrichment can't of course interfere with any particular experimental goals.

There is a slight disconnect since enrichment is not used in commercial production settings. If your experiment is supposed to mimic that commercial setting, you probably shouldn't provide enrichment. But wouldn't it be better if we turned that argument around? Why not provide enrichment in commercial facilities? I think this could be an interesting area of research. 

Broiler chickens are typically kept in buildings that house hundreds of thousands of birds and there is an accepted mortality rate of 2 to 5 %. If you could show that enrichment could reduce the average mortality by even 1%, it might be possible to convince commercial producers to give it a try. Of course, whatever enrichment you put in place must have a total cost of implementation and management that is less than the profit that a producer would get from that additional 1 % of birds that survive. 

All universities and companies who do animal research and who receive federal research dollars to do so are subject to intensive, repeated reviews and site visits by IACUC, Institutional Animal Care and Use Committees. The IACUC-specific paperwork associated with live animal experiments is thorough and time-consuming to complete.

Currently, the OSU IACUC has a bee in their bonnet about enrichment. I decided to give it a try. Our second feeding trial began 17 days ago. About one week in, I added stalks of celery to the pens. The chicks weren't too interested. Last weekend, a large tree branch from my neighbor's tree fell into my yard. I cut it up and hauled leafy branches to the barn, enough for each pen. The chicks didn't seem too interested. Keep in mind that modern broilers have been genetically selected for many generations to be eating, breast-meat-growing machines. Plus we keep them on a 23/1 light cycle: 23 hours of light, one hour of dark. Chickens don't eat when it is dark. So whenever they wake up from a nap, they start eating again.

My next enrichment experiment was straw. This morning, I divided a bale of straw into the 16 pens. According to the farm manager, "IACUC loves straw!" I won't really know how well the straw works until tomorrow or Friday.

A flake of straw, the dried out leafy branch, the wilted celery stalk. Enrichment. The chicks are more interested in the fresh water I gave them. They will be using the line watering system by the weekend.

We will be switching the chicks over to different diets next week. Once they settle into those, I'll put whole carrots in their pens. And I have a final enrichment experiment: shiny balls which I will make from aluminum foil. Apparently the farm manager has heard that ping pong balls can be used but I don't have any of those. I do have some foil in the cabinet.

The straw may be the only effective enrichment feature because they can climb on it, nest in it, and move it about by scratching in it (they can do this with their litter too but the straw is a different texture and composition). I at least have given enrichment for broiler chickens a try.