Hello this is classical salmonella pullorum disease of poultry.
It has high mortality in young chicken , while adults birds are mostly carriers and may die without any sign of illness. The disease has a white paste diarrhoea on the vent, birds tend to move near a source of heat.
It is common in free range poultry or backyard garden poultry.
On slaughter there are white hepatitic spots as shown on the liver, yellow deposits around the heart and the birds are emaciated.
Treatment is not recommended.
We advocate for prevention as a way to eliminate the disease.
Ensure you have biosecurity measures on the farm such as disinfectant and maintain hygiene.