Pathological findings in broiler chickens with malabsorption syndrome in Zimbabwe

A year-long study of pathological manifestations in broiler chickens with the malabsorption syndrome (MAS) was undertaken. A total of 52 cases comprising 368 chickens including formalin-fixed specimens were analysed. Gross and microscopic lesions were common in the pancreas and the intestines. Over 80% of the birds had pancreatic lesions characterised by fibrosis, while 75% had thin, dilated and mucus-filled intestines associated with villi sloughing and cellular infiltration in the duodenum and goblet cell hyperplasia in the jejunum. The severity of stunting was associated with intestinal bacterial infections, management systems, and the time during the course of the study period. Severe stunting and rickets were present during the first quarter of the study period, suggesting a vertical transmission during that period, while milder stunting was seen as the disease incidence subsided, suggesting a horizontal transmission and a gradual build-up of immunity by broiler parents.