Veterinary Services

Poultry and game birds

Multiple deaths were reported in commercial goslings aged five months. The birds were housed at night but grazed during the day. The two birds submitted were thin and had fluid intestinal contents, in which large numbers of motile protozoa were present. One of the two birds also had enlarged kidneys with pale streaks on the surface and cut surface (figure 6 - see top right-hand side). Histopathology subsequently showed that the collecting ducts were distended with large numbers of developing coccidial stages suggestive of Eimeria truncata. Initially there was a good response to tetracyclines administered in the drinking water, but mortality rose again two weeks after medication ceased. Further necropsies revealed caecal cores consistent with earlier damage to the digestive tract, but motile protozoa were not detected and there was no evidence of renal coccidiosis. Instead, mixed nematode burdens (Amidostomum species and Trichostrongylus species) were detected. Multiple parasitic problems (motile protozoa, renal coccidia, nematodes) were therefore present on this site, possibly because goslings had been reared here for many years.

Yersinia pseudotuberculosis infection was diagnosed in a unit of housed ducklings on the basis of bacteriology and histopathology. Listeria monocytogenes was isolated from the liver of a hen submitted from a rescue centre. The bird was emaciated, with evidence of diarrhoea Listeriosis in chickens can present as a systemic form or as an encephalitic form. Birds with the systemic form typically show emaciation and diarrhoea, as described in the current case. A range of nervous signs may be seen in birds with the encephalitic form.

Increased mortality was reported in red-legged partridges aged 16 weeks, approximately two weeks following purchase. Submitted birds were thin and many motile protozoa (Spironucleus species and trichomonads) were found in the small intestine and caeca. One bird also had a large focus of liver necrosis and histopathology showed a granulomatous bacterial hepatitis, most likely secondary to intestinal damage caused by the motile protozoa. Heavy burdens of gapeworms (Syngamus trachea) and coccidia were demonstrated in red-legged partridges from another estate, submitted with a history of respiratory distress.

Wild birds

Trichomoniasis caused further deaths among greenfinches (Carduelis chloris) and chaffinches (Fringilla coelebs). Pasteurella multocida was isolated from a house sparrow (Passer domesticus), possibly the result of injury inflicted by a cat. E coli with the profile of E coli O86 was considered to be the cause of death of a siskin (Carduelis spinus). The SAC considers that most cases of this disease occur in the spring and it is unusual to see it in October.