Egg-laying hens
As bad as conditions are for chickens raised for meat, they are even worse for birds in the egg industry. Erik Marcus, making a comparison to the better-publicized cruelty done to veal calves, says in his book
Meat Market: Animals, Ethics, and Money:
I personally believe that the average battery hen has it worse than the average veal calf. I think it’s probable that a forkful of egg comes at a cost of greater suffering than a forkful of veal… For people making a gradual switch to vegetarianism out of concern for animals, I therefore believe that the first food to give up should be, not meat, but eggs.
There are about 300 million laying hens in the United States; of these, some 95 percent are kept in wire battery cages, which allow each hen an average of 67 square inches of space—less than the size of a standard sheet of paper. For perspective, a hen needs 72 square inches of space to be able to stand up straight and 303 square inches to be able to spread and flap her wings. There is no room even for the hens to perform self-comforting behaviors such as preening and bathing. Hens are usually kept eight or nine to a cage; long tiers of these cages are built one upon another in sheds that hold tens of thousands of birds, none of whom has enough room to raise a wing. Excrement falls from the top cages to the lower ones, causing the same “ammonia burn” problem as in the broiler houses. Like chickens raised for meat, laying hens are debeaked as chicks. The hens are deprived of the ability to create nests for their eggs, which instead drop through the wires of the cage for collection. This inability to engage in instinctive behavior causes great frustration.
A sad side effect of the egg-production industry is the wholesale destruction of male chicks, who are useless to the egg industry. These chicks are not used in the meat industry either, because they have not been genetically manipulated for meat production. Male chicks are ground up in batches while still alive, suffocated in trash cans, or gassed.
The methods used to maximize production include manipulation of lighting to change the hens’ environment and hence their biological cycles; unnaturally long periods of simulated daylight encourage laying. Periodic forced molting creates an additional laying cycle: during this time, the hens are kept in darkness and put on a “starvation” diet (reduced-calorie feed) or starved altogether for up to two weeks.
Caged in this way, hens are unable to exercise, and constant egg production leaches calcium from their bones; these two factors cause severe osteoporosis, which leads to broken bones and great pain for the hens. The syndrome is called Cage-Layer Fatigue. Additionally, the wires of the cage injure the feet of the chickens, as the hens must sit in essentially one position their whole lives with their feet pressing into the wires. They rub against the sides of the cage, which causes severe feather loss and skin abrasions. In essence, hens who would normally be able to use their whole bodies and have lives as full as those of any other animal in nature are reduced to immobilized egg-laying machines, existing for that one purpose only.
The hens live like this for about two years or less, until their bodies are exhausted from the stresses of constant laying and their egg production decreases. At that point, they are shipped to slaughter to be turned into animal feed or sometimes human food or are simply discarded. In 2003 a public outcry brought attention to a California ranch that was reported to have discarded thousands of live hens using a wood chipper; no charges were brought because, as it turned out, this is a common industry practice.