Monday, August 10, 2009

The Great Egg Debate - Are Cage Eggs Better?

Most of the research on hen welfare contends that layers possess a higher state of welfare when raised on cage-free versus cage egg farms. However, in my upcoming book I provide some evidence as to why someone might prefer cage eggs even if they believe birds suffer less in cage-free egg production.

In Chapter 8, titled Your Eating Ethics, I create a farm animal welfare model which describes the consequences of various food choices in terms of farm animal welfare using a mathematical model. The model allows me to consider the welfare impacts of consuming cage or cage-free eggs. My research indicates that it requires more laying hens to produce an egg in a cage-free system than a cage system. The breed of bird used is less efficient, they suffer higher mortality rates, and they burn more energy walking. This simple fact has important implications for whether cage or cage-free eggs are more ethical.

Suppose that you must describe the overall welfare of laying hens on a scale of -10 to 10. A negative number indicates that the bird experiences more negative than positive emotions, and would be better off if it had never existed. A positive number indicates that its life was worth living, and the higher the welfare score the happier (or less miserable) is the bird.

Suppose that you assign birds in a cage egg facility a welfare score of -8 (negative eight, that is), and birds in a cage-free facility receive a welfare score of -6. You believe hens to be better off on a cage-free farm, but only slightly, and you believe both systems to provide miserable standards of care.

When I crunch the numbers, I find that you shoul prefer that people consume cage eggs. The reason is that each cage-free hen suffers less than their caged counterparts, but each egg produced requires more cage-free hens than a cage eggs, leading to a greater number of birds that suffer.

Consider an example. We start with 200 million hens in a cage system. Pretend that all of the U.S. converts to cage-free eggs and consumes the same amount of eggs. My calculations suggest it would require 324 million hens to produce the same amount of eggs. While the 200 million initial hens are given a better life, there are 124 million extra hens that lead miserable lives. The mathematics of my welfare model suggests the bad outweighs the good, and that cage eggs are more ethical, if eggs are going to be consumed.

Which is better: 200 million hens living in a cage system or 324 million hens living in a cage-free facility? See the tradeoff? Of course, if I alter the welfare score for cage-free hens to equal -4, cage-free eggs then become the ethical choice. The morality of cage versus cage-free eggs depends on the productivity of the birds and perceptions about bird welfare under each system.

I am not writing this in order to promote cage eggs, but to articulate the complexity of farm animal welfare. The morality of various food items depends on more than the welfare of each animal in the food system. I know that this added complexity may frustrate some readers who wish to discover an ethical diet but find the task daunting.

Better to accept the truth of complexity than a simple but false notion.