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81.
Cattle infested with all parasitic life-stages of Boophilus microplus (Canestrini) and B. annulatus (Say) were sprayed with 0.0125 or 0.025% active ingredient (AI) Amitraz. The detachment pattern of engorged or partially engorged females indicated that both concentrations of Amitraz caused premature detachment, with at least 90% of all females detaching within 24 h post-treatment. A large portion of the females collected during the first 24 h post-treatment were not fully engorged. The 2 tick species were equally sensitive to both concentrations tested. At 0.0125%, control of Index of Reproduction (IR) of B. annulatus was 98.9% while control of B. microplus was 97.8%. At 0.025% control of IR was 99.2 and 98.0% for B. annulatus and B. microplus, respectively. Amitraz adversely affected size and oviposition of females and the hatchability of eggs laid by treated females. Based on known detachment intervals of females after infestation, it appeared that Amitraz-treated animals were protected against larval reinfestation of both species for ca. 7 days at 0.0125% and for ca. 10 days at 0.025%. 相似文献
82.
Mycoplasmas identified as Mycoplasma canis were isolated from nine dogs with clinical signs of urogenital disease in Norway over a period of 20 months. Some of the dogs had been treated unsuccessfully with antibiotics, and three were euthanased as a result of severe persistent disease. Seven of the dogs had a urinary tract infection, one had chronic purulent epididymitis and one had chronic prostatitis. Overt haematuria was frequently observed among the dogs with cystitis. M canis was isolated in pure culture from seven of the dogs and in mixed culture from the other two. In three cases the mycoplasma was cultivated only from urinary sediment, and it was typically obtained in smaller numbers than would be considered indicative of a urinary tract infection. In contrast with most mycoplasmas, the M canis isolated from all the dogs grew on ordinary blood agar plates used for routine bacteriological cultivation. Specific mycoplasma media were not used and the presence of other Mycoplasma or Ureaplasma species cannot be excluded. 相似文献
83.
84.
Johnsen CK Jensen AN Ahrens P Andresen LO 《Veterinary immunology and immunopathology》2003,96(1-2):13-18
CCL27 (also named CTACK, ALP, ILC and ESkine) is a CC chemokine primarily expressed by keratinocytes of the skin. The cognate receptor of CCL27 named CCR10 (GPR-2), is also expressed in skin-derived cells, and in addition by a subset of peripheral blood T-cells and in a variety of other tissues. In this paper, we report the cloning of porcine CCL27 cDNA and investigation of CCL27 mRNA expression in Staphylococcus hyicus infected piglets. At the protein level, 77 and 74% homology was found to human and mouse CCL27 sequences, respectively. The results of the expression analyses show that CCL27 mRNA is upregulated in the skin of infected piglets and to a lesser extent in piglets recovered from disease and without clinical signs of infection, indicating a role for CCL27 both during inflammation and after recovery from an infection. 相似文献
85.
86.
Nicotinamide adenine dinucleotide (NAD)-dependent Pasteurellaceae other than Actinobacillus pleuropneumoniae and Haemophilus parasuis are frequently isolated from the respiratory tract of pigs. The taxonomic classification and relevance for pathogenicity of these bacteria deserves further attention. In the present study, 107 of these NAD-dependent isolates from the porcine respiratory tract, primarily from lungs with pathological changes, were investigated. On the basis of phenotypic criteria, such as haemolysis, urease, catalase, and indole formation as well as other fermentative activities, 50 of the isolates were assigned to Actinobacillus minor, 36 isolates to Actinobacillus porcinus and 21 isolates to Actinobacillus indolicus. However, many isolates among the three species showed fermentative activities differing from those of the respective type strain of the species. Serotyping on the basis of heat-stable polysaccharide antigens and 16 rDNA sequencing also revealed substantial heterogeneity within each of the three species although they clustered together in three distinct groups in the phylogenetic analysis. These three groups of NAD-dependent bacteria are different from, or in a borderline position, to the existing species or genera within the family Pasteurellaceae. A considerable number of isolates of these three groups were isolated in pure cultures from pneumonic lungs. Consequently, it will be necessary to critically review the opinion, that these NAD-dependent Pasteurellaceae are only "agents colonizing the mucosa". Further, taxonomic examinations of the strains within these three groups are indispensable to testing isolates for their virulence in gnotobiotic pigs. 相似文献
87.
A Feenstra E Bisgaard Madsen N F Friis A Meyling P Ahrens 《Zentralblatt für Veterin?rmedizin. Reihe B. Journal of veterinary medicine. Series B》1991,38(3):195-202
After an outbreak of mastitis in cattle caused by Mycoplasma bovis a study was made in 5 herds with recent cases (principal herds) and in 4 control herds. In the principal herds, M. bovis was isolated from milk samples, nasal swabs, and from one vaginal swab. M. bovis was also isolated from nasal swabs of calves in 2 of the 4 control herds, whereas all milk samples and vaginal swabs from the control herds were negative. Evaluation of serum antibody titres to M. bovis among non-mastitic animals of 3 principal herds and 1 control herd showed no difference in distribution of the titre values, which generally were low. However, cows excreting M. bovis in the milk had high antibody titres. The way of introduction to the herds and the spread of the infection within the herds could not be established by the study, which was supplemented by a DNA restriction fragment analysis of a number of M. bovis isolates. 相似文献
88.
S Bech-Nielsen W P Shulaw P L Frandsen J B Jorgensen N C Feld P Ahrens 《American journal of veterinary research》1992,53(8):1386-1391
Use of a dot-ELISA with serum adsorbed with Mycobacterium phlei or with nonadsorbed serum was compared. In addition, results attained using visual observation were compared with those obtained using a densitometer. Infection status of cattle was determined by results of culture of feces from a number of cattle with various degrees of exposure (low prevalence and test-negative) and disease manifestation (clinical suspect vs subclinical infection). Two paratuberculosis-negative herds, fecal culture-confirmed clinically suspect cases of paratuberculosis, and cows from 2 paratuberculosis-infected herds with diagnosis confirmed on the farm (low infection rate) were tested. Significant (P less than 0.05) increase in the dot-ELISA response was found in cattle with heavy M paratuberculosis shedding when nonadsorbed and adsorbed sera were used, compared with the response in cattle that were fecal culture-negative or were shedding M paratuberculosis at lower amounts. Paratuberculosis was diagnosed by visual determination in 29 of 44 (65.9%) of fecal culture-positive, clinically suspect cattle when nonadsorbed serum was used. Results of the visual test were negative in 85 of 93 (91.4%) of the fecal culture-negative cattle when nonadsorbed serum was used. However, when using M phlei-adsorbed serum, the sensitivity of the visual determination decreased to 34.1% (15/44), and the specificity increased to 97.8% (91/93).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
89.
Jørgensen PH Handberg KJ Ahrens P Manvell RJ Frost KM Alexander DJ 《The Veterinary record》2000,146(23):665-668
At present Denmark has the status of a 'non-vaccinating' country for Newcastle disease and its poultry population should therefore be free of antibodies to avian paramyxovirus 1 (APMV-1). Three live avian vaccines against infectious bronchitis, avian encephalomyelitis, and chick anaemia which had been found to be contaminated with APMV-1 viruses of low virulence for chickens were examined. The vaccines were produced by the same company and the affected batches had been used in Denmark in 1996/97. Furthermore, APMV-1 isolates of low virulence were obtained from three commercial broiler breeder flocks, one of which had been vaccinated with two of the contaminated vaccines. The flocks belonged to the same hatchery organisation. A comparison of viral F0 gene sequences and typing of virus isolates with a panel of monoclonal antibodies showed that the vaccine and field isolates were identical. 相似文献
90.