Veterinary Services

Four layers were submitted from a free-range unit experiencing elevated mortality. A combination of vent pecking and egg yolk peritonitis was found at post mortem examination. Sudden deaths of two adult layers from a different unit resulted from anaemia caused by heavy burdens of the red mite Dermanyssus gallinae.

The bulk of the avian submissions received in June were reared game birds. Rotavirus infection was suspected or confirmed in several batches of pheasants in the first two weeks of life. Fibrinous pericarditis, perihepatitis and splenomegaly were consistent post mortem findings in one batch of pheasants aged seven days – heavy growths of E. coli were isolated from the viscera and an underlying rotavirus infection was confirmed by polyacrylamide gel electrophoresis (PAGE). Non-starters and yolk sac infections were seen in pheasants and partridges in the first weeks of life, and unidentified environmental factors leading to failure to feed was considered to be the cause of mortality exceeding 25% in a batch of ducklings aged four days. Coccidiosis was diagnosed in pheasants and red-legged partridges between two and eight weeks of age. The incident involving pheasants aged two weeks occurred in houses in which flooding had occurred previously, and the wooden floor of the house under the litter may still have been damp, allowing greater survival of coccidial oocysts.

Six pheasant poults aged four weeks were submitted from a unit where the birds were reported to be "yawning". Respiratory tract lesions including diffuse lung consolidation, miliary white foci in the lungs and airsacculitis were found post mortem, an Aspergillus species was isolated from the lungs of some of the birds, and histopathology confirmed the presence of a multifocal mycotic granulomatous pneumonitis. Hexamitosis was diagnosed in pheasants aged five weeks, six weeks and seven weeks.

Salmonella Pullorum infection was demonstrated in adult pheasants from a unit where increased deaths and reduced egg production had been reported.