I found out about this interesting article at vegan.com. The article was written for the Scientific American blog by Julia Galef, a New York based writer with a B.A. in statistics who covers issues regarding science, philosophy and rationality.
In a nutshell, or maybe I should write “in an eggshell” Galef does some number crunching and concludes that from the perspective of deaths per calorie, eating fewer eggs kills is the second best food to eat less of to kill fewer animals. The first best is chicken:
The most striking result that falls out of this calculation is that eating eggs, as many vegetarians do, kills more animals than eating red meat
That might seem like an odd question for a vegetarian to have to concern himself with, but producing foods like eggs, milk and cheese – all of which are permitted on a typical vegetarian diet – does kill animals. Harvesting eggs and dairy doesn’t, in theory, require us to kill the laying hens or dairy cows, but in practice, modern factory farms do kill their hens and cows, at whatever point in the animals’ life cycles the farm considers to be the most profit-maximizing. For dairy cows, that’s usually at age 3-5, out of a natural 20-25 year lifespan. For egg-laying hens, it’s usually after one or two laying cycles. And since the male chicks of the laying species are useless to the egg farmer, they’re killed right after they hatch.
Number of animals killed to produce 1 million calories:
Chicken : 251