Interesting article in The Poultry Site dated July 2007 by A. Bruce Webster, Extension Poultry Scientist, University of Georgia College of Agricultural and Environmental Sciences. He concludes that there does not appear to be a good method at present for mass depopulation of commercial caged layer flocks in situations where humans could be infected by a disease carried by the birds.
Existing methods described briefly in this article either require extensive human-bird contact, which would probably be refused by the people assigned to remove the birds, or are likely to be impractical in the time frame required. Should an emergency arise that calls for mass depopulation of commercial caged layer flocks, it is difficult to think what might actually happen.
Although a mass depopulation event would be hard for any poultry company to cope with, it would be particularly devastating for an egg company with flocks concentrated in a complex of houses on one property. This and the lack of a good depopulation procedure make biosecurity a special imperative for the layer industry; even more so than for other sectors of the poultry industry. If an AI outbreak occurs in the vicinity of a commercial layer flock, vaccination of the flock may help contain the outbreak without going to the extreme of mass depopulation, provided biosecurity procedures have kept the flock shielded from the virus. Egg companies should seriously consider upgrading their biosecurity efforts.
This month, we started a project in China to develop a new method for mass depopulation of commercial caged layer flocks using the Anoxia method. This project is interesting because most industrial layer farms in China still use cages. With the current H7N9 outbreak in China, the development of such system is more than needed because depopulation of the layer hens on these farms would probably lead to situations where humans could be infected.
Read the article: Depopulation Methods for a Commercial Layer Flock