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41.
Laboratory methods designed to quantitate serum immunoglobulin were evaluated: single radial immunodiffusion, zinc sulfate turbidity, and serum electrophoresis. Estimation of immunoglobulin concentration in neonatle calves, using total protein measurements, was also evaluated. Single radial immunodiffusion proved useful for quantitation when either class or subclass information was needed. Zinc sulfate turbidity measurements gave accurate results for total immunoglobulin except when hemolysis was present in the sample. A correction factor for hemoglobin that will minimize errors resulting from hemolysis was presented. Serum electrophoresis was also found to be an accurate quantitation method. Large errors were encountered in attempting to estimate immunoglobulin on the basis of total protein.  相似文献   
42.
One-year old worm free, merino wethers, were each infected with 5000 H. contortus larvae of a strain resistant to mebendazole at a rate of 52 mg/kg body weight of sheep. After 21 days, they were assigned to two trials. The preliminary trial showed that mebendazole and levamisole acted synergistically on the H. contortus infection. In the second trial, sheep were treated with 0.35 mg/kg levamisole (one seventh the minimum effective dose against susceptible worms) or 40 mg/kg mebendazole (40 times the minimum effective dose against susceptible worms). In each case the anthelmintics did not reduce worm burdens, although mebendazole depressed egg production. However, when mebendazole and levamisole, at the above dose rates, were administered simultaneously, total worm counts in sheep were reduced by almost 60%. Similar results were obtained when the levamisole was administered 8 h or 14 h after mebendazole treatment. The implications of these observations for the treatment of benzimidazole-resistant haemonchiasis in sheep are discussed.  相似文献   
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REASONS FOR PERFORMING STUDY: Serum insulin concentration and its use as a prognostic indicator in horses with equine Cushing's syndrome (ECS) have been poorly documented. OBJECTIVES: To examine daily insulin variations in horses with ECS and the effect of treatment using trilostane, a competitive inhibitor of 3beta-hydroxysteroid dehydrogenase. Further, we aimed to examine the relationship between baseline serum insulin concentration and survival in horses with ECS. METHODS: Basal serum insulin concentrations were measured in 20 confirmed ECS cases by taking blood at regular 4 h intervals for 24 h (1200, 1600, 2000, 2400, 0400 and 0800 h) before treatment (Day 0) and 10 days, and 30 days and 1-2 years after the onset of trilostane therapy. The temporal pattern of insulin was analysed using a linear mixed model approach, and the prognostic value of measurements on Day 0 assessed using receiver-operating characteristic analysis. RESULTS: Horses with ECS showed a diurnal pattern of serum insulin concentration, highest value at 1200 h, and this pattern was not altered by treatment with trilostane. Furthermore, despite a mild increase of serum insulin concentrations after 10 days of trilostane therapy, insulin concentration was unaffected in the long-term. Low serum insulin concentrations at the beginning of the trial were significantly associated with improved survival to 1-2 years. The 1200 h sampling before treatment had the highest prognostic value for prediction of survival with a sensitivity and specificity of at least 90% for serum insulin at < 62 and > 188 microu/ml to predict survival and nonsurvival, respectively. CONCLUSIONS AND POTENTIAL RELEVANCE: Insulin is a useful prognostic indicator for ECS, but potentially large variations can occur throughout a 24 h period, indicating a single sample may not be representative. Serum insulin concentration did not increase over 1-2 years in horses receiving trilostane therapy.  相似文献   
45.
OBJECTIVE: To determine historical, physical, and clinical factors that may affect morbidity and mortality in horses with small intestinal volvulus unrelated to other causes (e.g., incarceration, lipoma, etc.). STUDY DESIGN: Retrospective study. ANIMALS: Client-owned horses (115), aged 1 month to 21 years. Methods: Data were obtained from medical records, identified by computer search and manual review. Continuous variables were compared between affected and non-affected horses with Mann-Whitney U-tests and non-continuous variables with Fisher's exact test (2 x 2 tables) or chi(2)-tests (larger tables). Stepwise logistic regression analysis was used to develop a multivariable model of the risk factors, taking account of confounding and interaction. RESULTS: Eighty percent of horses recovered from surgery survived to hospital discharge. Neither age, breed, nor sex was related to mortality. Survivors had a significantly lower heart rate, shorter capillary refill time, and better mucous membrane color. Variables associated with worsening cardiovascular status, increased hemoconcentration, and exudation of cells and protein into peritoneal fluid were significantly associated with non-survival. After recovery from surgery, the most serious complication was colic, which was significantly associated with non-survival (P=.028) as was a second celiotomy (P<.01). Both of these complications were associated with a jejunocecostomy during the first surgery. CONCLUSIONS: Significant differences in the clinical and clinicopathologic signs were identified between survivors and non-survivors. CLINICAL RELEVANCE: These findings can be used to make a scientific assessment of prognosis in the pre-operative, operative, and post-operative management of horses with small intestinal volvulus.  相似文献   
46.
Precise and direct dating of the Minoan eruption of Santorini (Thera) in Greece, a global Bronze Age time marker, has been made possible by the unique find of an olive tree, buried alive in life position by the tephra (pumice and ashes) on Santorini. We applied so-called radiocarbon wiggle-matching to a carbon-14 sequence of tree-ring segments to constrain the eruption date to the range 1627-1600 B.C. with 95.4% probability. Our result is in the range of previous, less precise, and less direct results of several scientific dating methods, but it is a century earlier than the date derived from traditional Egyptian chronologies.  相似文献   
47.
The objective of the study was to investigate constraints to dairy cattle health and production in rural smallholder communities in northern Vietnam, one of the target areas of the Vietnam government's dairy development programme. A total of 99 dairy farms (11 per commune) were recruited from 9 of 32 communes in Ba Vi District, using random two-stage cluster sampling. After the initial questionnaire interviews were conducted, farms were visited at three monthly intervals over a period of 1 year. Information on several health and production parameters relating to the study cattle was collected. Using multiple indicator modelling, it was found that Fasciola infestation, farmers who had been involved in dairying for longer (not indicative of better management skills), larger herd size, and cattle being kept in a shed were linked to reduced reproductive performances.  相似文献   
48.
Between 1990 and 2000, 317 herds of cattle in Northern Ireland were identified as being seropositive to Brucella abortus, and 68 per cent of them were attributed to transmission from neighbouring herds or to local spread. Of particular significance were three primary outbreaks in 1997, which resulted in significant secondary and tertiary spread. Three spatial clusters were identified, corresponding to two of the primary outbreaks, and the herd density and within-herd spread were highest in the largest cluster. Abortions in an infected herd and the disease-risk status of the disclosure test were positively associated with an increased within-herd prevalence.  相似文献   
49.
The aim of this study was to investigate the prevalence of wobbler disease within a Dobermann pinscher population from three geographical locations in New Zealand. The study population consisted of 138 adults (aged 1–13 years) and 32 puppies (aged 6 weeks to 11 months). Data collected for each dog included age, sex, geographic location, if a choker chain was used or not and, in adults, the following body measurements: dimensions of head length, head circumference, width between shoulders, neck length, height at withers and withers to rump length. In addition, lateral radiographs were taken of the caudal cervical vertebrae of each dog and the radiological abnormalities associated with wobbler disease scored, so that each dog could be assigned to one of three radiological groupings. Based upon a neurological examination, each animal was also placed into one of three neurological groupings. The relationship between radiological and neurological groupings and the independent variables was initially compared using a univariate and subsequently a multivariate analysis.

It was found that 48.8% of the dogs investigated had some abnormal radiological sign associated with wobbler disease, and 32.0% of them showed neurological signs. Dogs with radiological signs of the disease were 5.56 times more likely to have neurological signs. Statistical analysis of the data indicated that more severe radiological and neurological abnormalities occurred in the older dogs. In addition, dogs located in Hawke's Bay region had less chance of showing radiological changes than dogs from the other two regions, Hamilton and Wellington. Twelve of the 32 puppies were examined for radiological and neurological changes over the first year of their life. No abnormalities were detected in puppies under 12 weeks of age, but 28% (n=9) of the 32 puppies over 3 months of age did show some radiological changes. Only 9%(n=3) of puppies showed any neurological signs. Although several pedigree lines were investigated, the lineage data were incomplete, and therefore there was no conclusive evidence that wobbler disease was an inherited trait.

This study showed that, although the radiological signs of wobbler disease were present throughout a wide age range, the associated neurological changes tended to appear at a later age. In both instances, the severity of these changes increased with age.  相似文献   
50.
Objective To estimate the risks of anaesthetic and sedation‐related mortality in companion animals in the UK. (The Confidential Enquiry into Perioperative Small Animal Fatalities, CEPSAF). Study design A prospective cohort study with nested case–control study. Animal population All small animals anaesthetized and sedated at participating centres between June 2002 and June 2004. Methods Patient outcomes at 48 hours (alive, dead and killed) were recorded. Anaesthetic and sedation‐related death was defined as death where surgical or pre‐existing medical causes did not solely cause death. Species‐specific risks of anaesthetic‐related death and 95% confidence intervals (95% CI) were calculated. Risks were also estimated in the sub‐sets of dogs, cats and rabbits that were either healthy or sick (ASA 1–2 and 3–5, respectively). Results One hundred and seventeen veterinary practices participated in the study and 98 036 dogs, 79 178 cats and 8209 rabbits were anaesthetized and sedated. Overall risks of anaesthetic and sedation‐related death in dogs were 0.17% (1 in 601, 95% CI 0.14–0.19%), in cats 0.24% (1 in 419, 95% CI 0.20–0.27%) and in rabbits 1.39% (1 in 72, 95% CI 1.14–1.64%) within 48 hours of the procedure. In healthy dogs, cats and rabbits, the risks were estimated to be 0.05% (1 in 1849, 95% CI 0.04–0.07%), 0.11%, (1 in 895, 95% CI 0.09–0.14%) and 0.73% (1 in 137, 95% CI 0.54–0.93%), respectively. In sick dogs, cats and rabbits, the risks were 1.33%, (1 in 75, 95% CI 1.07–1.60%), 1.40% (1 in 71, 95% CI 1.12–1.68%) and 7.37% (1 in 14, 95% CI 5.20–9.54%), respectively. Postoperative deaths accounted for 47% of deaths in dogs, 61% in cats and 64% in rabbits. Most other small animal species had higher mortality risks. Conclusions and clinical relevance Small animal anaesthesia appears to be increasingly safe. Greater patient care in the postoperative period could reduce fatalities.  相似文献   
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