Impairment of coagulation function during aflatoxicosis in young chickens

Abstract

Reports of hemorrhagic episodes and high incidence of bruising in poultry during aflatoxicosis prompted an investigation of the effect of aflatoxin on parameters relating to hemostatic competence in chickens. Three-week-old broiler chickens fed dietary aflatoxin (0, 0.625, 1.25, 2.5, 5.0 and 10 μg/g of feed) were tested for specific coagulation responses. Tissue thromboplastin was found to possess two active components, one of which was lost during aflatoxicosis. Thromboplastin protein content was unaltered but lipid content was depressed at 10 μg/g. Factors VII and V activities and fibrinogen were reduced at 2.5 μg/g and above. Factor X activity was depressed at 5.0 and 10 μg/g. Prothrombin, the most sensitive factor tested, was reduced by 0.625 μg/g, the lowest dose fed. In addition, clot retraction in whole blood was measured, and it was found to increase with growth-inhibitory levels of aflatoxin. These data suggest that severe impairment of extrinsic and common clotting pathway functions occurs during aflatoxicosis in the chicken and that prothrombin is primarily affected during this coagulopathy.