Viral enteritis in certain galliformes - Literature review and own investigations in pheasants

SUMMARY Background: The efficient utilization of nutrients depends on a healthy GI tract, therefore in food animals, the integrity of the GI tract is of paramount importance. This is especially true for the young of the species. Damage to the GI tract early in life could result in irreversible damage to the flock.Objectives: The authors overview the viral enteritis of young chickens and turkeys and they report macroscopic, microscopic, bacteriological and PCR results in nine cases of acute enteritis in Hungarian pheasant farms.Materials and Methods: The pheasants were necropsied for post-mortem examinations. Appropriate tissue samples from the affected organs were fixed in 8% neutral-buffered formalin for 24 hours at room temperature, embedded in paraffin wax; and 3-4μm tissue sections were stained with haematoxylin and eosin for light microscopy examinations. Further samples were collected from the intestines for PCR assays to detect nucleic acid of enteral viruses. These samples were stored at -80 °C until completion of the assays. Samples were tested for rotavirus, reovirus, parvovirus, turkey astrovirus, and avian nephritis virus. For routine bacteriological examinations, small intestine content samples were aseptically collected and incubated for 24 hours at 37 °C under aerobic con-ditions on Columbia blood agar and Drigalski lactose agar.Results and Discussion:Of the nine pheasant flocks tested, four were nega-tive for PCR. Presumably, the overgrowth of Escherichia coli has caused disease and death in these flocks, due to poor hygiene conditions. Three of the other five flocks were detected with turkey astrovirus (TAstV), one with rotavirus, and one with avian nephritis virus. The macroscopic and microscopic findings were similar to those found in young galliform poultry species. Based on the results, the authors think that in addition to farm hygiene, various viruses play an important role in the enteritis of young pheasants. For uncomplicated viral enteritis, vitamins and probiotics may be recommended instead of antibiotic therapy