Gangrenous dermatitis is a subcutaneous infection in poultry. It is often due to clostridial organisms of various species, but can also be caused by Escherichia coli and staphylococcus.
Gangrenous dermatitis has become a major health problem among broiler flocks in the United States, resulting in high mortality, carcass condemnations and trimmed parts. Economic losses have been estimated to be as much as US$1.31 per affected bird.
Recent experience and trials suggest that late coccidial cycling predisposes birds to the development of gangrenous dermatitis. The disease tends to occur in flocks on chemical-to-ionophore and straight ionophore programs, which allow late coccidial cycling.
In contrast, flocks that are vaccinated against coccidiosis at one day-of-age have lifelong immunity against coccidiosis; they do not experience late coccidial cycling and tend not to develop gangrenous dermatitis.