Seroprevalence of Leptospira spp. in clinically healthy horses in Switzerland

A retrospective, cross-sectional study was conducted to determine the leptospiral seroprevalence in clinically healthy horses in Switzerland. A representative sample of 615 horse sera was examined by microscopic agglutination test for the presence of antibodies against 15 Leptospira?spp. serovars. In total, 58.5?% (n?=?360) of the horses were positive for one or more of the antigens analysed, with 20.3?% of them showing titres >=?400. The most prevalent serovar was Pyrogenes (22.6?%), followed by serovars Canicola (22.1?%) and Australis (19.2?%). Older horses, mares, ponies and animals spending increased time on pasture exhibited significantly higher prevalence rates (p?相似文献   

Owner assessment in judging the efficacy of airway disease treatment

Reasons for performing study: Efficacy of medications for recurrent airway obstruction is typically tested using clinical, cytological and lung function examinations of severely affected animals. These trials are technically challenging and may not adequately reflect the spectrum of disease and owner complaints encountered in clinical practice. Objective: To determine if owners of horses with chronic airway disease are better able to detect drug efficacy than a veterinarian who clinically examines horses infrequently. Method: In a double‐blinded randomised controlled trial, owners and a veterinarian compared the efficacy of dexamethasone (0.1 mg/kg bwt per os, q. 24 h, for 3 weeks; n = 9) to placebo (n = 8) in horses with chronic airway disease. Before and after treatment, owners scored performance, breathing effort, coughing and nasal discharge using a visual analogue scale (VAS). The clinician recorded vital parameters, respiratory distress, auscultation findings, cough and nasal discharge, airway mucus score, bronchoalveolar lavage fluid (BALF) cytology and arterial blood gases. Results: The VAS score improved significantly in dexamethasone‐ but not placebo‐treated horses. In contrast, the clinician failed to differentiate between dexamethasone‐ and placebo‐treated animals based on clinical observations, BALF cytology or endoscopic mucus score. Respiratory rate (RR) and arterial oxygen pressure (PaO₂) improved with dexamethasone but not placebo. Conclusions and clinical relevance: In the design of clinical trials of airway disease treatments, more emphasis should be placed on owner‐assessed VAS than on clinical, cytological and endoscopic observations made during brief examinations by a veterinarian. Quantifiable indicators reflecting lung function such as RR and PaO₂ provide a good assessment of drug efficacy.     

Effect of heterologous seminal plasma and semen extenders on motility of frozen-thawed ram spermatozoa

Ram seminal plasma increases the fertility of frozen-thawed ram spermatozoa deposited into the cervix. The aim of the current study was to compare the effect of ram seminal plasma to that of bull seminal plasma, dog prostatic fluid, protein-free TALP TrilEq (Triladyl with 0.5 mt of Equex STM paste added to each 100 mt) and heat-treated skim milk on longevity and percentages of progressively motile and aberrantly motile frozen-thawed ram spermatozoa. Three ejaculates from each of 6 rams were extended in TrilEq, pooled and frozen in straws as a single batch per ram. One hundred and eight straws (3 straws from each ram for each fluid) were thawed in random order. Once thawed, a straw was emptied into a tube with 0.85 ml of the appropriate fluid at 37 degrees C and kept at that temperature for 6 h. Motility was assessed at x200 magnification immediately (time zero) and 2, 4 and 6 h after thawing. Progressive motility decreased from each time to the next (P < 0.05) and was 39.0 % (0 h), 26.0 % (2 h), 19.6 % (4 h) and 12.6 % (6 h); SEM 1.24, n = 108 for each group. Ram seminal plasma resulted in higher progressive motility than bull seminal plasma, lower than milk, and similar to the other fluids. Ram seminal plasma resulted in lower aberrant motility than protein-free TALP and similar aberrant motility to other fluids. The effect of ram seminal plasma and dog prostatic fluid was very similar. The effect of ram seminal plasma on the fertility of frozen-thawed ram spermatozoa deposited into the cervix is not due an exceptionally beneficial effect on the motility of spermatozoa.     

Inheritance of equine sarcoid disease in Franches-Montagnes horses

The mode of inheritance for susceptibility to equine sarcoid disease (ES) remains unknown. The objectives of this study were to analyse a large sample of the Franches-Montagnes (FM) horse population and investigate the heritability and mode of inheritance for susceptibility to ES. Horses were clinically examined for the presence of sarcoid tumours. A standardized examination protocol and client questionnaire were used and a pedigree- and subsequent segregation-analysis for the ES trait performed. To investigate the mode of inheritance, five models were evaluated and compared in a hierarchical way.The analyses reveal that variation in susceptibility to ES is best explained by a model incorporating polygenic variation. The possible effect of a major gene, such as specific equine leukocyte antigen alleles, is unlikely, but cannot be ruled-out entirely. The heritability of the phenotype on the observation scale for the trait ‘affected with ES’ was estimated to be 8%. A corrected value for the heritability on a liability scale was estimated at 21% and it is therefore possible to estimate breeding values for ES. The arguments against the practical implementation of an estimated breeding value in a multifactorial condition like ES are discussed.     

Serum chlortetracycline concentrations in parrots fed medicated seed diets

Various seed diets containing chlortetracycline were fed to large and small parrots to evaluate serum chlortetracycline concentrations. The substitution of dehulled sunflower seed for whole sunflower in the seed mix may have resulted in higher chlortetracycline concentrations in cockatoos and parrots. The serum chlortetracycline concentration achieved for all diets was less than the goal of 1 μg/mL, but the concentrations attained may be useful for therapy.     

Two field strains of Haemonchus contortus resistant to rafoxanide

Two field strains of Haemonchus contortus, one from Pretoria on the Highveld and the other from White River in the Lowveld of the Transvaal, showed pronounced resistance to rafoxanide at a dosage rate of 7.5 mg/kg live mass per os. Both of these strains originated from kikuyu pastures under irrigation. Resistance in South Africa to rafoxanide and other anthelmintics, namely, closantel, ivermectin and the benzimidazoles is reviewed. It is concluded that apart from avoiding farming practices where integrated worm control is not possible, there is at present no solution to the problem of worm resistance in the country.