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排序方式: 共有3872条查询结果,搜索用时 62 毫秒
61.
Relave F Lefebvre RC Beaudoin S Price C 《The Canadian veterinary journal. La revue veterinaire canadienne》2007,48(8):823-826
The aim of this study was to validate an enzyme-linked immunosorbent assay (ELISA) for the measurement of progesterone (P4) in mares. Specifically, the objectives were as follows: (1) to determine the specificity and sensitivity of the ELISA test for determination of P4, (2) to measure the potential agreement between the 2 people performing the test, and 3) to evaluate the effect of time on the outcome. Ten mares were sampled on the day before ovulation (D-1), and on days 1 (D1), 3 (D3), and 5 (D5) following ovulation, during the reproductive season. While mares were cycling regularly, estrus was induced by the injection of 5 mg of prostaglandin (PGF2) and monitored starting on the 4th day by daily transrectal palpation and ultrasonography to determine the time of ovulation. Blood was collected and all samples (n=96) were assayed for P4 by a semiquantitative ELISA, by chemiluminescent immunoassay, and by radioimmunoassay (RIA). Based on the RIA, values of P4 on D-1, D1, D3, and D5 were significantly different (P < 0.0001) with mean and standard deviation(s) of 0.004, s = 0.52; 2.05, s = 2.58; 8.37, s = 4.17; and 12.76, s = 4.00 ng/mL respectively. The sensitivity and specificity of the semiquantitative assay were 94% and 95%, respectively for the lowest values of P4 (< 1.0 ng/mL). The value of kappa was 0.90 between 2 individuals performing the test. In conclusion, these results suggest that the semiquantitative test may be used reliably and economically to evaluate P4 levels in equine plasma in the clinical 相似文献
62.
Comparison of the results of abdominal ultrasonography and exploratory laparotomy in the dog and cat
Pastore GE Lamb CR Lipscomb V 《Journal of the American Animal Hospital Association》2007,43(5):264-269
Results of preoperative ultrasonography and exploratory laparotomy were reviewed retrospectively in a series of 100 small animals to assess the agreement between ultrasonographic and surgical findings and to identify abdominal lesions likely to be missed by ultrasonography. Good agreement occurred between ultrasound reports and surgical reports in 64% of the animals, which supported the use of ultrasonography in potential surgical candidates. A major discrepancy was observed between the ultrasound report and surgical findings in 25% of the animals. Of the various types of pathology encountered in the study, gastrointestinal ulceration or perforation was the most likely lesion to be missed by ultrasonography. 相似文献
63.
Chorioptes sp. mite infestation is increasingly recognized as a cause of skin disease in New World camelids and there is a need for an effective treatment protocol to eliminate herd infestation. In this field trial, eprinomectin applied topically at the rate of 0.5 mg kg(-1) weekly for 10 weeks was found to be ineffective in a herd of 12 llamas and 16 alpacas. 相似文献
64.
Bowman DD Torre CJ Mannella C 《Veterinary therapeutics : research in applied veterinary medicine》2007,8(4):293-304
Heartworm infection in dogs and cats in the western United States is a fairly new phenomenon, and for this reason it is often considered to be of minimal significance.The purpose of this survey was to collect data from 11 western states (Arizona, California, Colorado, Idaho, Montana, Nevada, New Mexico, Oregon, Utah, Washington, and Wyoming) in an effort to assess awareness of heartworm disease and identify areas in which improvement in understanding is needed. To accomplish this goal, veterinary clinics and hospitals in these states were sent a one-page survey in early 2006. The results of the survey demonstrate that cases of heartworm disease have been reported in all 11 states, illustrating the importance of annual testing and the routine use of preventives. 相似文献
65.
Williamson KK Willard MD McKenzie EC Royer CM Payton ME Davis MS 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2007,21(5):924-927
BACKGROUND: Omeprazole reduces the severity of exercise-induced gastritis but not the prevalence of gastric lesions in sled dogs. The frequent feeding of sled dogs during competition likely results in decreased absorption of omeprazole and, thereby, decreased efficacy. HYPOTHESIS: Famotidine, a histamine-2 blocker with good bioavailability in the presence of food, would reduce the incidence and severity of exercise-induced gastric disease in sled dogs. ANIMALS: Sixteen fit Alaskan sled dogs (4 female, 12 male, all intact, age 2-6 years). METHODS: Dogs were randomly assigned to treatment (22 mg famotidine PO q24h) or control groups (n = 8 per group). Famotidine was administered with a meal to the treatment group once daily for 7 days before a challenge and once during exercise. Control dogs were fed an identical diet as the principal group. The 16 dog team completed a 100-mile exercise challenge in 18 hours. A gastroscopy was performed 24 hours after the challenge. The appearance of the mucosa was scored by an individual by using a scoring system. RESULTS: Treatment with famotidine significantly reduced the severity score compared with control (P = .0004). No adverse effects of treatment were reported. CONCLUSIONS AND CLINICAL RELEVANCE: Famotidine is effective in reducing the severity of exercise-induced gastric disease in racing Alaskan sled dogs, with minimal to no adverse effects, and may be recommended for prophylactic use in short distance races. 相似文献
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68.
Impact of cash crop cultivation on household income and migration decisions: Evidence from low-income regions in China
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This study examines the impact of cash crop cultivation on household income and migration decisions, using survey data collected from low-income regions in China. Given farmers decide themselves whether to cultivate cash crops, an endogenous treatment regression model that accounts for potential selection bias issue is used to analyze the data. The empirical results show that cash crop cultivation exerts a positive and statistically significant impact on household income, but it does not affect household migration decisions significantly. The disaggregated analyses reveal that cash crop cultivation significantly increases farm income but decreases off-farm income. 相似文献
69.
Christopher Marlowe A. Caipang 《Aquaculture International》2013,21(3):591-603
The gastro-intestinal tract serves as the route of infection of most bacterial pathogens in fish, and the immune response genes in the gut produce substances that provide an initial defense during pathogen invasion. The expression of some genes involved in antibacterial defense, cell-mediated immunity and inflammation in the distal intestine of Atlantic cod, Gadus morhua L., was investigated following intraperitoneal vaccination with heat-killed Vibrio anguillarum. Tissue samples of the distal intestine were collected at 0, 1, 3, 7 and 10 days post-vaccination (dpv) and processed for semi-quantitative RT-PCR analyses. Expression of the bactericidal/permeability-increasing protein/lipopolysaccharide-binding protein (BPI/LBP), g-type lysozyme, non-specific cytotoxic cell receptor protein-1 (NCCRP-1) and interleukin-8 (IL-8) significantly increased during the early stages post-vaccination, that is, 1–3 dpv, followed by a decrease in their expression returning to their initial levels. Transferrin and apolipoprotein A-I, although weakly expressed in the distal intestine, also increased in the vaccinated fish. Interleukin-1β (IL-1β) was significantly decreased in its expression level relative to the PBS-injected fish at 3 and 7 dpv. The expression of these immune-related genes in the distal intestine as a result of vaccination provides valuable information on the mechanisms of gut immunity in the fish against pathogenic bacteria, particularly during the early stages of infection. 相似文献
70.
Menghe H Li Edwin H Robinson Brian G Bosworth Daniel F Oberle Penelope M Lucas 《Aquaculture Research》2010,41(8):1133-1139
Two experiments were conducted to evaluate various ingredient combinations in a 28% or 32% protein diet for optimum performance of channel catfish Ictalurus punctatus. All diets contained soybean meal and corn, but with or without cottonseed meal, wheat middlings or fish meal (FM). Channel catfish fingerlings were stocked into 0.04 ha earthen ponds at 18 530 fish ha?1. Fish were fed one of eight diets once daily to apparent satiation for two growing seasons. Results demonstrated that the dietary ingredient composition used had significant effects on fish performance, but magnitude of differences was relatively small. Overall, diets containing FM resulted in greater weight gain (Experiments 1 and 2) and lower feed conversion ratio (Experiment 1) than fish fed all‐plant diets. However, certain combinations of plant ingredients provided the similar fish growth as some diets containing FM. There were no significant differences in weight gain between fish fed soybean meal–corn or soybean meal–corn–wheat middlings‐based diets with cottonseed meal or FM. The use of wheat middlings in the diet had no significant effects on fish production characteristics. 相似文献