Veterinary Services

Avian tuberculosis was diagnosed in adult hens from two small backyard flocks. Multiple focal lesions were present in the liver and spleen of the two birds examined and Ziehl-Neelsen stained smears demonstrated numerous acid-fast bacilli with the morphology of Mycobacterium avium. The classical form of Marek’s disease resulted in paresis and paralysis in two hens aged approximately one year from a backyard flock and the acute form of Marek’s disease was diagnosed in an 18-month-old chicken that became dull and died.

Respiratory infections were noted in hens from several hobby flocks, often associated with mucoid or purulent sinusitis. Infection with Mycoplasma gallisepticum was considered to be the most likely cause. Affected birds were often in poor body condition and some had concurrent infectious diseases – one bird had a severe necrotising typhlitis consistent with histomoniasis, and one bird from a different flock had a thickened crop from which Candida albicans was isolated, a very thickened proventriculus from which C. albicans and "megabacteria" (avian gastric yeasts) were demonstrated, and fluid caecal contents in which many trichomonads were present.

Four turkeys aged eight weeks were submitted from a flock of 250 birds, with a history of yellow diarrhoea, deterioration in litter quality, poor appetite, ill-thrift and increased mortality. Lesions typical of histomoniasis (blackhead) were present in the liver and caeca of the birds.

Problems seen in younger turkeys included starveouts and yolk sac infection in the first week of life. On one unit losses due to yolk sac infection continued into the second week of life with an associated peritonitis. Deaths in turkeys aged five weeks were the result of "round heart disease" or spontaneous turkey cardiomyopathy – the cause of this condition is unclear but may reflect damage to the heart muscle in the first week of life.

The number of gamebird submissions fell, as expected, during October. Coccidial infections were detected in four-month-old pheasants and five-month old partridges submitted with histories of lethargy and not feeding. Significant numbers of gapeworms (Syngamus trachea) and intestinal hairworms were found in red-legged partridges aged four months, and heavy gapeworm burdens were also found in pheasants aged five months from a different site.