BOVINE LEUKOCYTE ADHESION DEFICIENCY - CLINICAL COURSE AND LABORATORYFINDINGS IN 8 AFFECTED ANIMALS

The clinical course of Bovine Leukocyte Adhedsion Deficiency (BLAD) in eight Holstein Friesian cattle is described. Affected animals were pr esented with a history of poor thriving and recurrent bacterial infect ions. Five of these animals had to be killed because of severe respira tory disease shortly after admittance. Three affected animals survived calfhood only as a result of frequent antibacterial treatments. At on e year of age, failure to thrive and stunted growth were still evident , but infections requiring antibiotic treatments occurred only sporadi cally. Clinical manifestations of BLAD were found in the digestive sys tem (gingivitis, periodontitis, alveolar periostitis, diarrhoea), the respiratory system and the skin (impaired wound healing, chronic derma titis). A leukocytosis based on a mature neutrophilia, which persisted during infection-free periods, was observed in all animals. Granulocy tes were substantially deficient of beta2-integrin expression on their membranes. Anaemia which was noted in four animals, may be related to the Anaemia of Inflammatory Disease Complex (AID). The serum total pr otein content increased with time and was associated with elevated gam ma-globulin levels. We suggest that, at a certain age, animals affecte d with BLAD are able to cope with environmental agents due to compensa tory mechanisms of the immune system.