Morphometric evaluation of "dysbacteriosis" in broilers.

In consequence of the withdrawal of products that assisted animal production, such as antimicrobial growth promoters, once-controlled enteric diseases have returned and new multifactorial diseases causing gut disorders of unknown origin have emerged in broilers. One of these widespread syndromes causing intestinal health problems in broilers is in the field referred to as "dysbacteriosis". During the present study, the histopathology of the intestinal tract of broilers affected with dysbacteriosis was analysed. Commercial broilers were given a macroscopic dysbacteriosis score by experienced veterinarians during necropsy. Samples from the duodenum and caecum were taken from each broiler for histopathological analysis. An increase in the macroscopic dysbacteriosis score coincided with increased villus atrophy, a decrease in the thickness of the tunica muscularis and an increase in T-lymphocyte infiltration in the gut mucosa. Also more and larger goblet cells were observed in the animals with high macroscopic dysbacteriosis scores. Although the exact aetiology still remains to be identified, dysbacteriosis in broiler chickens thus coincides with an inflammatory reaction in the gut mucosa.