Demonstration of Ornithobacterium rhinotracheale in pheasants (Phasianus colchicus) with pneumonia and airsacculitis.

Outbreaks of respiratory disease were investigated in reared pheasants (Phasianus colchicus) aged approximately 18 to 32 weeks, released into the semi-wild on four shooting estates in southern England. The clinical signs in the affected birds included swelling of the face and eyes, loss of condition, gasping respirations and coughing. The gross pathology findings included sinusitis, airsacculitis, pleural oedema and lung lesions. The histopathological findings in the affected lungs were characterized by a granulomatous pneumonia. Ornithobacterium rhinotracheale (ORT) was isolated from respiratory tract tissues, and 16S rRNA gene sequencing on three isolates revealed two distinct genotypes, one previously associated with some electrophoretic type (ET) 1 strains and the other a novel genotype that clustered among sequences previously associated with ET 3, ET 4, ET 5 and ET 6 isolates. The localization of ORT within the lung tissue was demonstrated by fluorescent in-situ hybridization in the bronchial exudate of three cases, although not within the granulomatous lesions themselves. In each case, ORT was identified as part of a complex of other respiratory agents including avian paramyxovirus type 2, avian coronavirus, Mycoplasma gallisepticum, Mycoplasma synoviae and other Mycoplasma species, Escherichia coli, Pasteurella multocida, other Pasteurellaceae and Syngamus trachea, suggesting synergism with other agents. Exposure to other intercurrent factors, including adverse weather conditions and internal parasitism, may also have exacerbated the severity of disease.

Investigations into an outbreak of corvid respiratory disease associated with Pasteurella multocida.

The possible cause of disease and mortality in corvids on an outdoor pig unit in the north of England between August 2007 and March 2008 was investigated. Nine carrion crows (Corvus corone corone) and nine rooks (Corvus frugilegus), comprising five live-caught birds with clinical signs of respiratory disease, one live-caught bird without respiratory disease, and 12 birds submitted dead were examined. Clinical signs, gross and histopathological examination, microbiology and toxicology indicated that Pasteurella multocida infection was the cause of disease. Molecular and serotyping analyses showed that P. multocida isolates (obtained from live-caught birds with clinical respiratory disease) were all capsular type F with a mix of somatic serotypes 3, 4 and 7. Immunohistochemistry increased the diagnostic sensitivity of the analysis and detected P. multocida within the pulmonary lesions of all affected live-caught birds and 10 of 12 birds found dead. These findings suggest that wild corvids in the UK can suffer from lung pathology associated with P. multocida and, as potential vectors of P. multocida, may pose a risk to domestic poultry.

Detection of a coronavirus from turkey poults in Europe genetically related to infectious bronchitis virus of chickens.

Intestinal contents of 13-day-old turkey poults in Great Britain were analysed as the birds showed stunting, unevenness and lameness, with 4% mortality. At post mortem examination, the main gross features were fluid caecal and intestinal contents. Histological examination of tissues was largely unremarkable, apart from some sections that showed crypt dilation and flattened epithelia. Negative contrast electron microscopy of caecal contents revealed virus particles, which in size and morphology had the appearance of a coronavirus. RNA was extracted (turkey/UK/412/00) and used in a number of reverse transcription-polymerase chain reactions (RT-PCRs) with the oligonucleotides based on sequences derived from avian infectious bronchitis virus (IBV), a coronavirus of domestic fowl. The RT-PCRs confirmed that turkey/UK/412/00 was a coronavirus and, moreover, showed that it had the same partial gene order (S-E-M-5-N-3' untranslated region) as IBV. This gene order is unlike that of any known mammalian coronavirus, which does not have a gene analogous to the gene 5 of IBV.The gene 5 of the turkey virus had two open reading frames, 5a and 5b, as in IBV and the coronaviruses isolated from turkeys in North America. The turkey/UK/412/00 also resembled IBV, but not mammalian coronaviruses, in having three open reading frames in the gene encoding E protein (gene 3). The percentage differences between the nucleotide sequences of genes 3 and 5 and the 3' untranslated region of turkey/UK/412/00 when compared with those of IBVs were similar to the differences observed when different strains of IBV were compared with each other. No sequences unique to the turkey isolates were identified. These results demonstrate, for the first time, that a coronavirus was associated with disease in turkeys outside of North America and that it is a Group 3 coronavirus, like IBV.

Renal neoplasia in coypus (Myocastor coypus).

Renal neoplasia is described in coypus (Myocastor coypus) from a feral population of the species in East Anglia. A population control campaign was started in 1962, and in 1981 this became an eradication scheme. From 1976 onwards, a research programme included the postmortem examination of 9400 wild caught and captive coypus. During the period 1980-91, 15 cases (0.16%) of renal neoplasia were detected. The tumours were found in both sexes between estimated ages of 25 months and 13 years with no significant sex prevalence. There was no clear evidence that renal tumours were more common in older animals. Tumours were most common in captive coypus and were bilateral in approximately half of the animals. In all cases, the tumours were of epithelial type resembling adenomata and adenocarcinomata of other animals. Most were clearly benign, and, although some showed evidence of malignancy, no unequivocal evidence of metastasis was established. The prevalence of renal tumours in this series is greater than that recorded in previous published surveys of coypus and other rodents. This may relate to the origin of the coypus population, differences in age structure in animals examined, and the varied conditions under which the rodents lived. Aetiological factors remain undetermined.

Pheasant ataxia: a new condition in pheasant poults.

Between 1995 and 1997 a neurological condition in pheasant poults from 24 sites in England and Scotland was investigated. Affected birds showed varying degrees of ataxia and incoordinated movements and, in severe cases, recumbency, but generally remained alert with their heads held upright. The condition characteristically affected poults from seven weeks of age and the incidence on any one site was low. No significant bacteria were isolated consistently from brain tissue. The condition was characterised histologically by a non-suppurative meningoencephalitis, in which lesions were found predominantly in the cerebellum in 61 of 81 samples examined (75.3 per cent). A non-suppurative myelitis was recorded in 16 of 20 spinal cords examined. No lesions were recorded in peripheral neural tissue and lesions were rare in other tissues. The condition appeared not to have been recorded previously in pheasants. A viral aetiology was suspected but Newcastle disease virus was not involved.