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1.
A technique is described for biopsy of the bovine udder, employing sedation and local anaesthesia. Tissue samples of approximately 5 g were obtained by electrocautery from two quarters of the udder of a cow laterally recumbent. Care was taken to ensure complete haemostasis which was achieved by electrocoagulation and ligation. Postoperative recovery was rapid, and loss of yield was no greater in biopsied glands than in control glands of the same cow. Yield from all quarters returned to preoperative levels within 48 h.  相似文献   
2.
On a property in the Nelson District, blood and urine samples were taken from red deer (Cervus elaphus) from which low (<1:100) antibody titres to serovar copenhageni and suspected leptospiral abortions had previously been reported. A total of 27 hinds were sampled. Microscopic agglutination test (MAT) titres in sera ranging from 1:32 to 1:128 were found in six animals. Thirteen leptospiral isolations were made from nine of the 27 urine samples. Four of these were typed as copenhageni and nine as hardjo. Two cultures were prepared from each urine sample and hardjo and copenhageni were both isolated from single urine samples from two animals. None of the 27 deer had serum MAT titres at 1:32 or above to copenhageni.  相似文献   
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A total of 417 isolates of Escherichia coli collected from five animal species/organ system combinations from swine [urinary/genital tract (UGT) incl. mastitis metritis agalactia syndrome], horses [genital tract (GT)] and dogs/cats [respiratory tract (RT), UGT and gastrointestinal tract (GIT)] were analysed quantitatively for their susceptibility against different antimicrobial agents by determination of minimum inhibitory concentrations. Regardless of which animal species the strains originated from, resistance appeared most frequently against sulfamethoxazole (18-59%), tetracycline (14-54 %), and ampicillin (14-39%). High percentages of intermediate isolates were observed for cephalothin (39-46 %). In general, low prevalences of resistance were detected for amoxicillin/clavulanic acid (1-4%), gentamicin (1-9%), and cefazolin (0-11%). Generally speaking, the antimicrobial resistance situation among E. coli isolates from horses and small animals is relatively good.  相似文献   
6.
A total of 92 canine/feline Pasteurella multocida strains form respiratory tract infections or infections of skin/ear/mouth as well as 42 canine/feline Bordetella bronchiseptica strains from respiratory tract infections were investigated for their susceptibility to antimicrobial agents. While the P. multocida strains were susceptible to all antimicrobial agents tested - except sulfonamides -, a considerable number of the B. bronchiseptica strains was resistant or exhibited high MIC values against a number of antimicrobial agents including penicillin G, oxacillin, cefazolin, ceftiofur, cefquinome, sulfamethoxazole, and trimethoprim/sulfamethoxazole.  相似文献   
7.
Rubber mats covering concrete slatted flooring are a developing market in dairy barns but remain rare in beef cattle facilities. The aim of this study was to investigate the effects of covering slatted concrete floor with perforated rubber mats on behaviour and occurrence of skin and claw lesions in fattening bulls. The groups of six bulls each with a total average age of 9.8 months were kept over 1 year on either slatted concrete (CONCRETE PEN) or on slatted concrete covered completely (RUBBER PEN) or partially (CHOICE PEN) with perforated rubber mats. Every quarter-year, behaviour (preference of flooring, lying, aggression, mounting) was recorded. In two-weekly intervals the incidence of skin lesions was examined. At 12 and 18 months of age the rising time of the bulls was measured. At the beginning of the study and after slaughter claw dimensions were recorded. Bulls in the CHOICE PEN preferred (P<0.01) the rubber coated area throughout the experiment. Animals in the RUBBER and the CHOICE PENS showed more lying periods (P<0.01) and had a lesser incidence of skin lesions (P<0.01) compared to bulls in the CONCRETE PEN. Bulls in the CHOICE PEN needed less time for rising (2.7+/-0.3s) than bulls in the CONCRETE PEN (4.4+/-0.5s, P<0.01). Net claw growth differed significantly between all pens (RUBBER>CHOICE>CONCRETE; P<0.05). In conclusion, the results of this study indicate that rubber coated slatted flooring has a positive influence on the housing conditions of beef cattle.  相似文献   
8.

BACKGROUND

A reduction in chasmothecia, an important inoculum of grape powdery mildew (Erysiphe necator Schwein.), is essential for disease control in vineyards; the use of fungicides during the formation of chasmothecia on vine leaves, late in the growing season, may accomplish this. Inorganic fungicides, such as sulphur, copper, and potassium bicarbonate, are very useful for this purpose because of their multisite mode of action. The aim of this study was to evaluate chasmothecia reduction using different fungicide applications late in the growing season in commercially managed vineyards and in an exact application trial.

RESULTS

Chasmothecia on vine leaves were reduced in commercial vineyards by four copper (P = 0.01) and five potassium bicarbonate (P = 0.026) applications. The positive effect of potassium bicarbonate was also confirmed in the application trial, where two applications showed lower chasmothecia numbers than the control (P = 0.002).

CONCLUSION

The application of inorganic fungicides reduced the amount of chasmothecia as the primary inoculum source. Potassium bicarbonate and copper are of further interest for disease control as these fungicides can be used by organic and conventional wine growers. The application of these fungicides should be carried out as late as possible before harvest to reduce chasmothecia formation and, consequently, the potential for powdery mildew infestation in the subsequent season. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.  相似文献   
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Brucella abortus vaccines composed of native cell envelopes or outer membrane proteins of smooth strain 2308 were compared with a vaccine (PG) composed of the insoluble residue of strain 2308 cell envelopes which had been extracted with hot sodium dodecyl sulfate. Vaccines were given by injection in an oil base adjuvant containing trehalose dimycolate and muramyl dipeptide or without adjuvant. Mice vaccinated with 30 micrograms native cell envelopes or PG and challenged 4 weeks later with virulent B. abortus strain 2308 displayed equivalent levels of protective immunity at 1 and 4 weeks post-infection. Heifers were vaccinated with 5 mg of antigens in adjuvant; PG was also administered without adjuvant. Humoral and cell mediated immune (CMI) responses were tested at monthly intervals. PG without adjuvant induced negligible immune responses. Native cell envelope antigens induced significantly higher titers of whole cell agglutinins over a 3-month period than did PG, although revaccination with PG in adjuvant enhanced the production of agglutinins and both vaccines induced antibodies to the O polysaccharide. Lymphocyte blastogenesis responses and delayed hypersensitivity reactions to porin and group 3 proteins were stimulated by both native and PG vaccines, and the magnitude of the responses did not differ significantly between the treatment groups. These vaccines were therefore comparable in their capacity to induce protective immunity in mice and CMI responses in cattle, whereas antibody responses induced by PG in cattle were generally lower. These findings provide a basis for evaluation of nonliving B. abortus vaccines in cattle.  相似文献   
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