Veterinary Services

Viral haemorrhagic disease of rabbits was tentatively diagnosed on a farm premise. Mortality was reported to be 87 per cent. Examination of two female rabbits that died suddenly revealed extensive pulmonary congestion in both rabbits. There was evidence of pulmonary haemorrhage and ‘nutmeg’ liver in one animal and multifocal micro-abscessation throughout the liver parenchyma of the second animal. Moderate to large numbers of coccidial oocysts were detected in the intestinal contents and faeces of both. Histopathology of tissues from the first rabbit revealed extensive hepatic portal necrosis with individual necrotic cells scattered throughout the parenchyma, diffuse pulmonary congestion and oedema. Histopathology of tissues from the second rabbit revealed extensive necrosis of individual hepatocytes throughout the hepatic parenchyma. Major bile ducts were hyperplastic, dilated and fibrosed with coccidial forms in the epithelium and lumen. There was extensive portal fibrosis and biliary hyperplasia. Viral haemorrhagic disease was diagnosed, with hepatic coccidiosis in the second rabbit, on the basis of the history, gross findings and histopathology findings. 

Exotic animals

Intermittent vomiting and mucoid diarrhoea were reported in two ferrets in a multi-ferret household a few weeks after the introduction of a new ferret. One of the affected ferrets died and was submitted for postmortem examination when histopathological examination confirmed some changes typical of epizootic catarrhal enteritis of ferrets. Electron microscopy of faeces is in progress for evidence of coronavirus. The second ferret made an uneventful recovery.

Fish

A rainbow trout was submitted from a pond stocked with trout for over 10 years. Over the preceding four days, one dead fish had been found each day. Although postmortem degeneration limited examination of the fish, water analysis confirmed the presence of an ammonium-nitrogen level in excess of the upper acceptable limit and consistent with environmental enrichment.