EXPERIMENTAL ACUTE GASTRIC DILATATION AND VOLVULUS IN THE DOG: CHANGES IN BIOCHEMICAL PARAMETERS*

Acute gastric dilatation and volvulus with dilatation were produced in 11 dogs anesthetized with halothane. Blood samples were taken during these procedures for biochemical analyses. Serum potassium did not change significantly during the experimental procedure, but there was a significant increase (p<0.05) after release of the dilatation with volvulus. Renal function was impaired with significant increases (p<0.05) in the serum concentration of urea nitrogen, phosphorus, and creatinine. Evidence of cellular damage was reflected by a significant elevation (P<0.05) in glutamic-oxaloacetic transaminase activity. Serum glucose concentration increased significantly (P<0.05) during experimental gastric dilatation and dilatation with volvulus.     

Ten years of bovine virus diarrhoea virus (BVDV) control in Norway: a cost-benefit analysis

A retrospective cost-benefit analysis was carried out on the Norwegian bovine virus diarrhoea (BVD) control and eradication strategy, for the years 1993-2003. Information regarding the control cost input parameters was gathered from the cattle industry (TINE Norwegian Dairies, GENO Breeding and AI association, and GILDE Norwegian Meat), The National Animal Health Authorities and The Veterinary Institute. We accounted for variable costs (both direct costs associated with the control, and those costs carried by the farmers as a consequence of the control program). The benefit was estimated as the difference between the assumed losses without control - represented overall as 10% increase of the observed 1993 BVD virus infection level - and the observed losses during the control period. An estimate of the financial losses associated with the BVD virus (BVDV) infection was based on studies of the herd level effects on health, reproduction, and production in dairy herds with evidence of recent BVDV infection. We used a stochastic simulation model to account for the total uncertainty in both the control cost and financial loss estimates. The annual net benefits over the 10 years of BVD control were discounted to a 1993 net present value (NPV). The median NPV of the BVD control, nationally, was estimated at 130 million NOK with a distribution of the NPV ranging from +51 to +201 million NOK (5th and 95th percentiles, respectively). Out of the total control costs the farmers and the farmer-owned industries (the co-operatives) had carried about 62% of these costs; however, the farmers were also the main beneficiaries. The Norwegian experience shows a robust cost-efficiency for a BVDV eradication strategy; this stands in sharp contrast to earlier studies where the results were not supportive. Even though every cattle population and country is unique, the Norwegian findings and experiences should have wider implications.     

Evaluating predictors of apple scab with receiver operating characteristic curve analysis

ABSTRACT Apple scab (Venturia inaequalis) is a perennial threat to apple production in temperate climates throughout the world. In the eastern United States, apple scab is managed almost exclusively through the regular application of fungicides. Management of the primary phase of disease is focused on preventing infection by ascospores. Management of secondary cycles of infection is largely dependent on how well primary infections were controlled. In this study, we used receiver operating characteristic curve analysis to evaluate how well mid-season assessments of the incidence of apple scab on cluster leaves, clusters (i.e., the whorl of cluster leaves), or immature fruit can serve as predictors of apple scab on harvested fruit (harvest scab) and whether these mid-season assessments of scab could be used reliably to manage scab under various damage thresholds. Results showed that assessment of scab on immature fruit was superior at predicting harvest scab than were assessments made on clusters or cluster leaves at all damage thresholds evaluated. A management action threshold of 7% scab incidence on immature fruit was identified by Youden's index as the optimal action threshold to prevent harvest scab incidence from exceeding 5%. Action thresholds could be higher or lower than 7% when economic assumptions were factored in to the decision process. The utility of such a predictor is discussed.     

Rush allergen specific immunotherapy protocol in feline atopic dermatitis: a pilot study of four cats

Rush immunotherapy has been shown to be as safe as conventional immunotherapy in canine atopic patients. Rush immunotherapy has not been reported in the feline atopic patient. The purpose of this pilot study was to determine a safe protocol for rush immunotherapy in feline atopic patients. Four atopic cats diagnosed by history, physical examination and exclusion of appropriate differential diagnoses were included in the study. Allergens were identified via liquid phase immunoenzymatic testing (VARL: Veterinary Allergy Reference Labs, Pasadena, CA). Cats were premedicated with 1.5 mg triamcinolone orally 24 and 2 h prior to first injection and 10 mg hydroxyzine PO 24, 12 and 2 h prior to first injection. An intravenous catheter was placed prior to first injection. Allergen extracts (Greer Laboratories, Lenoir, North Carolina) were all administered subcutaneously at increasing protein nitrogen units (pnu) every 30 minutes for 5 h to maintenance dose of 15,000 pnus ml-1. Vital signs were assessed every 15 minutes. Two cats developed mild pruritus and the subsequent injection was delayed 30 minutes. No changes in either cat's vital signs were noted, nor was there any further pruritus. All four cats successfully completed rush immunotherapy. Two cats developed a dermal swelling on the dorsal neck one week later. In these four cats, this protocol appeared to be a safe regimen to reach maintenance therapy. A larger sample of feline patients is needed to determine the incidence of adverse reactions and to follow the success of ASIT based upon this method of induction.     

Comparison of proteoglycan and collagen in articular cartilage of horses with naturally developing osteochondrosis and healing osteochondral fragments of experimentally induced fractures

OBJECTIVE: To compare articular cartilage from horses with naturally developing osteochondrosis (OC) with normal articular cartilage and healing cartilage obtained from horses with experimentally induced osteochondral fractures. SAMPLE POPULATION: 109 specimens of articular cartilage from 78 horses. PROCEDURE: Morphologic characteristics, proteoglycan (PG), and type II collagen were analyzed in articular cartilage of OC specimens (group 1), matched healing cartilage obtained 40 days after experimentally induced osteochondral fractures (group 2), and matched normal cartilage from the same sites (group 3). RESULTS: 79 specimens of OC cartilage were obtained from horses. Ex vivo PG synthesis was significantly greater in the femoral cartilage, compared with synthesis in the tibial cartilage, and significantly greater for groups 1 and 2, compared with group 3. For groups 1 and 2, femoral fragments had significantly greater PG content, compared with PG content in tibial fragments. Keratan sulfate content was significantly less in group 3, compared with groups 1 and 2. Cartilage from the OC specimens had loss of structural architecture. The OC tissue bed stained positive for chondroitin sulfate and type II collagen, but the fracture bed did not. CONCLUSIONS AND CLINICAL RELEVANCE: Our analyses could not distinguish articular cartilage from horses with OC and a healing fracture. Both resembled an anabolic, reparative process. Immunohistochemical analysis suggested a chondromyxoid tissue in the OC bed that was morphologically similar to fibrous tissue but phenotypically resembled hyaline cartilage. Thus, tissue in the OC bed may be degenerative cartilage, whereas tissue in the fracture bed may be reparative fibrous callus.     

Evaluation of a lithium dilution cardiac output technique as a method for measurement of cardiac output in anesthetized cats

OBJECTIVE: To evaluate the use of a lithium dilution cardiac output (LiDCO) technique for measurement of CO and determine the agreement between LiDCO and thermodilution CO (TDCO) values in anesthetized cats. ANIMALS: 6 mature cats. PROCEDURE: Cardiac output in isoflurane-anesthetized cats was measured via each technique. To induce different rates of CO in each cat, anesthesia was maintained at > 1.5X end-tidal minimum alveolar concentration (MAC) of isoflurane and at 1.3X end-tidal isoflurane MAC with or without administration of dobutamine (1 to 3 microg/kg/min, i.v.). At least 2 comparisons between LiDCO and TDCO values were made at each CO rate. The TDCO indicator was 1.5 mL of 5% dextrose at room temperature; with the LiDCO technique, each cat received 0.005 mmol of lithium/kg (concentration, 0.015 mmol/mL). Serum lithium concentrations were measured prior to the first and following the last CO determination. RESULTS: 35 of 47 recorded comparisons were analyzed; via linear regression analysis (LiDCO vs TDCO values), the coefficient of determination was 0.91. The mean bias (TDCO-LiDCO) was -4 mL/kg/min (limits of agreement, -35.8 to + 27.2 mL/kg/min). The concordance coefficient was 0.94. After the last CO determination, serum lithium concentration was < 0.1 mmol/L in each cat. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated a strong relationship and good agreement between LiDCO and TDCO values; the LiDCO method appears to be a practical, relatively noninvasive method for measurement of CO in anesthetized cats.     

Efficacy of boric-complexed zinc and acetic-complexed zinc otic preparations for canine yeast otitis externa

The purpose of this 2-week, double-blinded, controlled clinical trial was to evaluate the efficacy of topical amino acid-complexed zinc gluconate formulated with boric acid (ZGB) or acetic acid (ZGA) versus a topical placebo in the treatment of yeast otitis externa in dogs. Included in the study were dogs with otitis externa and a cytopathological finding of yeast organisms in the affected ear. Ears were treated with the placebo, ZGA, or ZGB medications. Yeast counts as well as clinical appearance of the ears were monitored. Results revealed that ZGB significantly reduced the number of yeast organisms in cases of otitis externa.