Bacillary white diarrhea, also referred to as pullorum disease, is an acute highly fatal disease of young chicks due to
Salmonella enterica subsp.
enterica Gallinarum-Pullorum. Symptoms of the disease can appear at any time after hatching, until the birds are 3 weeks old.
Affected birds have little or no appetite, can barely sit or stand without swaying, and appear drowsy, droopy, and uninterested in their surroundings. Their droppings are a distinctive white-cream color, sticky and shiny, and may be mixed with a brownish material. This causes what's known as 'pasty butt'. If the dried up fecal material isn't cleaned from their vent, it can cause a fatal blockage. Sometimes passing the droppings is painful for the chicks, resulting in cries of distress when they defecate. The chicks rapidly grow weaker, have a harder time breathing, and eventually die a day or two after signs are first observed.
Most chicks will not survive the course of the disease. Some chicks may recover, however they will remain carriers of
S. pullorum, and during times of stress may shed the bacteria in their feces. If the chickens are used for breeding or egg laying purposes, they will pass
S. pullorum vertically through their eggs, and to their offspring.
In the United States, many commercial chicken breeders participate in the
National Poultry Improvement Plan (NPIP). The program was established in the early 1930s to coordinate State programs aimed at eliminating PD and other egg-transmitted diseases of chickens and other poultry, to offspring. Flocks that participate in NPIP are required to conduct periodic blood testing on adult breeding birds, to ensure that they aren't carriers.
Transmission
S. pullorum can be transmitted to chicks multiple ways:
- From laying hens to their offspring
- Direct or indirect contact with infected flock members (bird-to-bird contact, cannibalism or feather pecking of infected flock members, contaminated wounds, shed in feces that contaminates the environment, feeder, and waterer)
- Contamination of incubator or associated equipment
- Wild birds, rodents, wildlife, and insects (such as flies)
Incubation period
The incubation period is from a day to ten days.