Zentralblatt fur Veterinarmedizin. Reihe B. Journal of veterinary medicine. Series B最新文献

A third component of complement (C3) capture enzyme-linked immunosorbent assay was used to determine the concentration of IgG circulating immune complexes (CIC) in 91 dogs with naturally acquired leishmania infection and in a control group of 24 healthy dogs. Results were expressed as a percentage of a reference standard. Mean concentrations of CIC were significantly (P < 0.001) higher in leishmania-infected dogs (228.725 +/- 14.283%) than in controls (74.542 +/- 12.614%). An increase in CIC concentration was found in 57.1% of the leishmania-infected dogs. No significant differences could be recorded in CIC levels between males and females in either group. Infected dogs showing hypercreatininemia rendered a statistically significant (P < 0.030) higher serum CIC concentration than sick dogs with normal creatininemia. When hypercreatininemia (> or = 1.30 mg/dl) was used as an indicator for CIC increase, the positive predictive value obtained was 0.9 indicating that renal function impairment was associated with high serum CIC concentration in 90% of the infected dogs.

Adherence of an encapsulated (UT 101) and a non-encapsulated (UT 102) strain of Streptococcus uberis to a bovine mammary epithelial cell line (MAC-T) and to extracellular matrix proteins (ECMP) including fibronectin, collagen and laminin was investigated. S. uberis was co-cultured at 4 degrees C with MAC-T cell monolayers. Both strains of S. uberis adhered to MAC-T cells. However, the non-encapsulated strain of S. uberis adhered better to MAC-T cells than the encapsulated strain. Preincubation of MAC-T cells with lipoteichoic acid (LTA) and/or treatment of S. uberis with antibodies directed against the carboxyl-terminal half of type 24 M protein reduced adherence of both strains of S. uberis to MAC-T cells. Adherence to ECMP was measured by incubating bis-carboxyethyl-carboxyfluorescein acetomethyl ester (BCECF-AM) labelled S. uberis in 96-well plates coated with fibronectin, collagen or laminin. Both strains adhered to ECMP, however, the encapsulated strain adhered better to ECMP than the non-encapsulated strain. Results of this investigation demonstrated that both strains of S. uberis evaluated were capable of adhering to bovine mammary epithelial cells and to ECMP. Adherence of S. uberis to mammary epithelium may be an extremely important mechanism in the establishment and progression of bovine intramammary infections.

The genus morbillivirus presently comprises measles virus of man, rinderpest virus (RPV), peste des petits ruminants virus (PPRV), and canine distemper virus (CDV). 'Emerging' morbilliviruses, such as phocid distemper virus (PDV) of seals, dolphin (DMV) and porpoise morbillivirus (PMV) have probably been present for a long period of time and outbreaks are possibly related to introduction into a highly susceptible population and/or be the result of interspecies transmission. In this review some comparative aspects of morbillivirus infections, particularly with respect to rinderpest and canine distemper viruses, are presented. Topics include pathogenesis, epidemiology, molecular phylogeny, diagnosis and prophylaxis. Recent developments in molecular biology have created tools which have enabled us to achieve a better understanding of morbillivirus infections at the nucleic acid level ('molecular epidemiology') while recombinant DNA technology has allowed new bivalent recombinant vaccines with improved heat stability to be produced.

Tumour necrosis factor-alpha (TNF alpha) and interleukin-6 (IL-6) were detected in the intra-carpal synovial fluids collected from aborted and recently dead young calves. Five out of seven TNF-alpha positive joint fluids were bacteriologically positive and two were sterile. Only one out of 20 TNF-alpha negative joint aspirates was infected (P = 0.0014). Sixteen of the synovial fluid samples were examined for the presence of IL-6. In 12 samples IL-6 was detected, six of which were bacteriologically contaminated. Four out of the 16 samples were IL-6 negative. These findings indicated the possible association between TNF-alpha and the intra-articular inflammatory processes in young calves, which in the present study were either found in combination with or without IL-6.

Brain samples were collected from 514 voles and wild mice in Estonia, and examined for rabies. The samples were tested with antigen ELISA, and 8.6% of them additionally by virus isolation assay. The results were negative. Our data show that in areas of north-eastern Europe, where rabies is endemic in raccoon dogs and red foxes, populations of smaller mammals may remain free of rabies.

Investigations into optimal culture conditions for Bacillus cereus in order to detect bacterial toxins in a cell culture system showed that Dulbecco's modified Eagle's medium supplemented with 5% fetal calf serum is the medium best suited for this purpose. The highest toxicity levels were seen when bacteria were cultured at 21 degrees C. In 42 of 43 Bacillus cereus-strains isolated from milk and milk products, toxin formation was detected using the MTT-test. In 11 strains, toxin formation was even shown when bacteria were cultured at 4 degrees C. When culture supernatants were examined in a commercially available ELISA, all cytotoxic strains were shown to form diarrheal toxin.

The establishment of two indirect sandwich polyclonal ELISAs for the virological diagnosis of rabbit haemorrhagic disease (RHD) and European brown hare syndrome (EBHS) is described. Each assay uses rabbit and guinea pig antisera raised to RHD or EBHS purified virus particles. The tests are sensitive and specific, but cross-reactions between rabbit haemorrhagic disease virus (RHDV) and European brown hare syndrome virus (EBHSV) are observed. Most rabbit liver homogenates identified as RHDV-positive by ELISA do not haemagglutinate human red blood cells at room temperature.

The European brown hare syndrome virus (EBHSV) and the rabbit haemorrhagic disease (RHDV) virus were inoculated in hares and rabbits to discover whether the homologous and heterologous host could be infected. The aims were to confirm the results of previous studies that showed the existence of antigenic differences between these two viruses, and also to define the role attributed to the hare in transmission to rabbits of a disease, EBHS, initially mistaken for RHD. During the trials, clinical symptoms and pathological lesions were noted, and virological and serological analysis were conducted, using specific tests set up for both diseases. The hares infected with EBHSV died of an acute form of EBHS, whereas the rabbits remained healthy. The low serological response in these rabbits towards the EBHSV did not protect them against RHDV. Similarly, hares inoculated with RHDV remained healthy and showed a low anti-RHDV antibody titre but died when challenged with EBHSV.

Lung samples from pneumonic lesions in cattle and goats, naturally or experimentally infected with strains of the Mycoplasma mycoides cluster, were fixed in formalin and embedded in paraffin. An immunohistochemical technique using monoclonal or polyclonal antibodies was performed on tissue sections in order to detect Mycoplasma antigens. Four monoclonal antibodies (MAbs), one (2A3) raised against M. mycoides ssp. mycoides small colony (SC) and large colony (LC), two (1D3 and 5E5) against M. mycoides ssp. capri, and one (5A10) against M. bovis, were used. A range of polyclonal antibodies, raised to the individual subspecies of the M. mycoides cluster, and one to Pasteurella haemolytica, was also used. The MAb 2A3 showed positive immunostaining in lung sections from cattle and goats naturally and experimentally infected with M. mycoides ssp. mycoides SC and LC, but not with pneumonic lesions of cattle and goats due to other members of the M. mycoides cluster, M. bovis or Pasteurella spp. The MAb 1D3 showed immunostaining in lung sections from goats naturally and experimentally infected with M. mycoides ssp. capri, but again not with pneumonic lesions caused by other members of the M. mycoides cluster, M. bovis or Pasteurella spp. The MAb 5E5 immunoreacted in sections from pneumonic lesions from all animals infected with one of the three M. mycoides cluster subspecies used in the study, but not with M. bovis or Pasteurella infected tissue. Immunoreaction was mainly found in the cell debris around necrotic areas, as well as in macrophages, neutrophils and epithelial cells. The localization of antigens of the M. mycoides cluster using polyclonal antisera followed basically the same pattern as that obtained with the monoclonals. However, a wide cross reactivity was found between different antisera and relatively high background immunostaining was also seen, especially in necrotic areas. The results suggest that immunohistochemical methods using monoclonal antibodies are useful tools for the diagnosis and study of the pathogenesis of pneumonia caused by the Mycoplasmas of the M. mycoides cluster.

Prototheca sp., a colourless algae, is quite common in dairy environments, particularly in wet areas contaminated with manure. The main purpose of this paper is to describe an outbreak of clinical bovine mastitis in an 86-cow dairy herd in the State of Säo Paulo, Brazil. Prototheca sp., an achlorophyllous algae, were isolated on blood agar (incubated for 24 h at 37 degrees C) from 11 quarters of seven lactating Holstein cows, and from one quarter of a cow at the end of the dry period. Treatments were applied, but there was only a microbiological cure, not a functional one. Diagnosis of Prototheca sp. in any of the cows in the herd indicates a herd problem. Infected animals usually have markedly reduced milk production and granulomatous changes often occur in the mammary gland. All sources of contact between the teat ends and drainage water or damp areas should be corrected. An all-out effort for strict sanitation, including during milking, should be made so that the teat ends will not become contaminated.