Tuesday, September 15, 2009

One Study Favors Cage Eggs

I have been searching for a study that compares and ranks egg production systems that puts the cage system equivalent or ahead of cage-free. All the rankings thus far favor cage-free systems, so I have been on the lookout for one that doesn't.

A study in New Zealand may or may not be this contrary study supporting cage egg production.

This study compared cage systems, cage-free systems, and free-range systems, finding that all birds in every system were adapted to the production system and had acceptable welfare standards. The cage system was not considered to be inferior or superior to other systems. This could be considered an important finding, as it is the first real study that did not conclude cage-free systems are superior to cage systems.

However, if you look at how the study was conducted it was perhaps a foregone conclusion. The various sytems were evaluated by mortality rates, feather loss, injuries, physical performance, stress-hormone levels, and the like, and it was already known that cage systems do well on these factors (that is my perception, at least).

What this study did differently was not not assign any credit to cage-free and free-range systems for allowing birds room to walk and express normal behaviors like foraging. Previous studies did give cage-free/free-range systems credit for this, and was largely the deciding factor in determining cage-free was better.

The study indirectly admits this, saying that laying hens have said to suffer in cage conditions by other people because they are unable to perform almost any natural behavior or even walk, and that, "These perceptions of conventional cages will probably not be dispelled by the results of this survey. Nevertheless, a high level of adaptation is, at the very least, a necessary condition for good bird welfare, and the behavioral results of this study show that birds in cages appear as well adapted to their environment as free range and barn hens are to theirs."

It should also be noted that, according to a personal source who is an expert in animal welfare and intimately involved in the welfare issue, that the findings of reports like the Laywel Report were also a foregone conclusion. This person told me that the people involved with the Laywel Report were going to rank cage-free ahead of cage systems regardless of what the mortality rate in the cage-free system was. When the report was written they made it seem as if the mortality rate realized was "acceptable" in return for the freedom it provides the birds, but in reality, almost any rate would have been acceptable. I may be wrong, but that is what I was told.

I believe that there is no bottom-line in the cage-free vs cage egg debate. I give cage-free systems credit for allowing birds the room to walk and such, and that is why I prefer cage-free, but other people don't. And if you do give credit for this feature, how much? The answers to these questions depends on perceptions, and I have mine, but other people have theirs as well.