Salmonellosis (Pullorum, Bacillary white diarrhoea)

Vertically spread through egg (transovarian) or on egg (by faecal contamination) or by feed and water contamination, contaminated incubators, exploding eggs, and bird to bird (horizontal) transmission. It is species specific (occurs in birds only).

Young birds have a pasted vent. White diarrhoea, huddling, lameness, somnolence (sleepy), laboured breathing and blindness can occur. Mortality peaks at 7-10 days with up to 100% mortality and/or morbidity. Adults are usually subclinical and a drop in egg production, fertility or hatchability may occur. Depression, anorexia (won’t eat), diarrhoea and dehydration are occasionally seen.

Young birds have a red-streaked liver, enlarged spleen and grey nodules in the peritoneum. White caecal plug, misshapen yolk and omphalitis (swollen navel) can occur. White areas on gizzard, liver, heart, lungs, swollen joints and swollen urate filled kidneys may be seen.

Some countries still vaccinate using modified live vaccines. Control rodents and reduce poultry by products in the feed.

It is a notifiable disease. It has been eradicated from most commercial flocks around the world (by testing and slaughter of positive breeder flocks, but is still common in backyard flocks and commercial flocks in third world countries. A few isolated outbreaks of pullorum occasionally occur in broiler breeder and broiler flocks from more developed countries.