V. Benetka

Subclinical Infection with Avian Influenza A H5N1 Virus in Cats

Infection without disease may occur under natural conditions after contact with infected birds.

Prevalence of feline coronavirus types I and II in cats with histopathologically verified feline infectious peritonitis.

Abstract Feline coronaviruses (FCoV) vary widely in virulence causing a spectrum of clinical manifestations reaching from subclinical course to fatal feline infectious peritonitis (FIP). Independent of virulence variations they are separated into two different types, type I, the original FCoV, and type II, which is closely related to canine coronavirus (CCV). The prevalence of FCoV types in Austrian cat populations without FIP has been surveyed recently indicating that type I infections predominate. The distribution of FCoV types in cats, which had succumbed to FIP, however, was fairly unknown. PCR assays have been developed amplifying parts of the spike protein gene. Type-specific primer pairs were designed, generating PCR products of different sizes. A total of 94 organ pools of cats with histopathologically verified FIP was tested. A clear differentiation was achieved in 74 cats, 86% of them were type I positive, 7% type II positive, and 7% were positive for both types. These findings demonstrate that in FIP cases FCoV type I predominates, too, nonetheless, in 14% of the cases FCoV type II was detected, suggesting its causative involvement in cases of FIP.

Detection of Bovine Torovirus in Neonatal Calf Diarrhoea in Lower Austria and Styria (Austria)

Summary Faeces of 230 calves with and without diarrhoea collected during the winter period 2004/2005 in 100 Austrian farms (Styria and Lower Austria) were examined for viral, bacterial and parasitic enteropathogens. Torovirus‐specific nucleic acid confirmed by reverse transcriptase‐polymerase chain reaction was found in 12 of 230 calves (5.2%). Ten of these calves were clinically ill, several of them showing signs of dehydration and abnormal faecal consistency at the time of sampling. Computer assisted analysis of two nucleotide sequences obtained from Austrian bovine samples revealed 93% similarity to Breda strain, but only 71% or 52% similarity to Equine Berne or Porcine Markelo torovirus strains respectively. Phylogenetic analysis grouped Austrian torovirus samples into the Bovine torovirus cluster indicating the first detection of Bovine torovirus in Austria. In addition, the following agents were detected in bovine faecal samples: Bovine coronavirus, 25.7%; Escherichia coli, 17%; Cryptosporidium spp., 11.7%; Eimeria spp., 10.4%; Rotavirus, 9.1%; Clostridium perfringens, 9.1% and Giardia spp., 6.1%. Salmonella spp. was not detected.

Influence of communal Alpine pasturing on the spread of pestiviruses among sheep and goats in Austria: first identification of border disease virus in Austria.

The purpose of this investigation was to determine the influence of communal Alpine pasturing on the spread of pestivirus infections among sheep and goats. The study included 481 sheep from 23 farms and 131 goats from 26 farms pastured on separated Alpine meadows in the western part of Austria. At the starting of pasturing on the sheep meadow, 325 (67.6%) animals were seropositive, on the goat meadows in 16 (12.2%) samples antibodies to pestiviruses were detected. At the end of pasturing, 74 seronegative sheep and two seronegative goats had seroconverted. Between the beginning and the end of pasturing the seroprevalence in sheep increased significantly from 67.6% to 83% (P < 0.05). Moreover, in the peripheral blood mononuclear cells of four sheep, pestivirus‐specific RNA was detected before as well as after pasturing; these animals remained serologically negative throughout the investigation. They were, therefore, identified as persistently infected. Sequence analysis in the Npro region revealed that the detected pestiviruses were the same at genetic level and they were grouped into the Border disease virus (BDV)‐3 genotype. No pestivirus RNA was found in goat samples. The results of this survey indicate that communal Alpine pasturing does play a key role in the spread of BDV. Moreover, BDV has been identified and characterized for the first time in sheep in Austria, which until then had been regarded as being free from BD.

Pestivirus Exposure in Free-living and Captive Deer in Austria

During the hunting season of 2001–02, blood and spleen samples from 59 red deer (Cervus elaphus), 77 roe deer (Capreolus capreolus), four fallow deer (Dama dama), and five chamois (Rupicapra rupicapra) were collected from nine hunting districts (n=133) and one deer farm (n=12) in southern Austria. Sera were tested for antibodies against bovine viral diarrhea virus (BVDV) with an enzyme-linked immunosorbent assay (ELISA) and virus neutralization tests against three BVDVs and one border disease virus strain. Reverse transcriptase polymerase chain reaction was used for detection of pestivirus-specific RNA in spleen samples. Antibodies were detected in one serum sample when using ELISA and virus neutralization tests. Results of the virus neutralization tests of this sample provided strong evidence for the exposure to the BVDV-1 genotype. The spleen samples were negative for pestivirus-specific RNA.

Simultaneous Canine Distemper Virus, Canine Adenovirus Type 2, and Mycoplasma Cynos Infection in a Dog with Pneumonia

The present case is the first description of a triple infection with canine distemper virus (CDV), canine adenovirus (CAV) type 2, and Mycoplasma cynos in a dog. The 5-month-old female Miniature Pinscher was euthanized because of dyspnea, croaking lung sounds, weight loss, and lymphopenia. Pathologic examination revealed a fibrinous necrotizing pneumonia with large amphophilic intranuclear and acidophilic intracytoplasmatic inclusion bodies in different lung cells. Immunohistochemically, CDV antigen was present in lung and many other organs. In situ hybridization for detection of CAV nucleic acid showed positive signals in the lung only. Polymerase chain reaction of lung tissue and consecutive sequencing of the amplification product identified CAV type 2. Bacteriologic examination of lung tissue yielded large amounts of M cynos. This infection was confirmed by immunohistochemistry detecting abundant positive signals in the lung tissue.

Canine adenovirus type 2 infection in four puppies with neurological signs

Four nine- to 11-week-old puppies developed respiratory and neurological signs due to an infection with canine adenovirus type 2 (CAV-2); three of these were euthanased. They had moderate, diffuse pneumonia but there were no histological abnormalities in the central nervous system. Adenovirus-specific nucleic acid was detected by PCR in samples of lung and brain and the amplified product was 99·8 per cent homologous with the CAV-2 reference strain Toronto A26/61. The positive PCR result was confirmed by in situ hybridisation in samples of lung, liver and spleen, but not in brain, and CAV was isolated in cell culture from lung material; PCRs for canine distemper virus and canine herpesvirus-specific nucleic acids were negative, but large amounts of Bordetella bronchiseptica were isolated from lung material.

M gene analysis of atypical strains of feline and canine coronavirus circulating in an Austrian animal shelter

Coronavirus-positive samples of faeces collected in an Austrian animal shelter from 12 cats and 10 dogs were analysed by reverse transcriptase-pcr with primers amplifying a segment of the M protein gene, and by sequence analysis. In addition, the samples were subjected to S gene typing, using primers that differentiated between feline coronavirus (fcov) types I and II. A phylogenetic analysis of the M gene sequences revealed not only clearly segregating canine coronavirus (ccov) in the dogs, typical ccov sequences and the recently described fcov-like ccov, but also at least two genetic clusters of fcov in the cats, one species-specific, the other more closely related to fcov-like ccov. The M gene sequences of these new feline strains had at most 88 per cent identity with the fcov-like ccov strain 259/01 and only up to 85 per cent with any fcov sequence available in GenBank. In the phylogenetic tree they occupy an intermediate position between feline and canine coronaviruses.

Coronavirus infection of spotted hyenas in the Serengeti ecosystem

Abstract Sera from 38 free-ranging spotted hyenas (Crocuta crocuta) in the Serengeti ecosystem, Tanzania, were screened for exposure to coronavirus of antigenic group 1. An immunofluorescence assay indicated high levels of exposure to coronavirus among Serengeti hyenas: 95% when considering sera with titer levels of ≥1:10 and 74% when considering sera with titer levels of ≥1:40. Cubs had generally lower mean titer levels than adults. Exposure among Serengeti hyenas to coronavirus was also confirmed by a serum neutralisation assay and an ELISA. Application of RT-PCR to 27 fecal samples revealed viral RNA in three samples (11%). All three positive fecal samples were from the 15 juvenile animals (<24 months of age) sampled, and none from the 12 adults sampled. No viral RNA was detected in tissue samples (lymph node, intestine, lung) from 11 individuals. Sequencing of two amplified products from the S protein gene of a positive sample revealed the presence of coronavirus specific RNA with a sequence homology to canine coronavirus of 76 and 78% and to feline coronavirus type II of 80 and 84%, respectively. Estimation of the phylogenetic relationship among coronavirus isolates indicated considerable divergence of the hyena variant from those in European, American and Japanese domestic cats and dogs. From long-term observations of several hundred known individuals, the only clinical sign in hyenas consistent with those described for coronavirus infections in dogs and cats was diarrhea. There was no evidence that coronavirus infection in hyenas caused clinical signs similar to feline infectious peritonitis in domestic cats or was a direct cause of mortality in hyenas. To our knowledge, this is the first report of coronavirus infection in Hyaenidae.

Use of latissimus dorsi and abdominal external oblique muscle for reconstruction of a thoracic wall defect in a cat with feline osteochondromatosis

A 4-year-old, male castrated European shorthair cat was presented with a firm mass palpable on the right caudal rib cage. Lateral and ventrodorsal radiographs of the thorax revealed a 4×3×2 cm large, expansile and radiodense mass originating from the distal part of the 13th rib. After removal of the tumour, which was histopathologically confirmed as feline osteochondromatosis, the diaphragm, omentum, external abdominal oblique and latissimus dorsi muscles were used to reconstruct the defect. Feline osteochondromatosis is induced by retroviruses, eg, feline leukaemia virus, for which the cat tested positive. The tumour was removed for palliative reasons, because such tumours have the tendency to transform into osteosarcomas. Six months after the surgical excision the cat showed no clinical signs of reoccurrence.