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排序方式: 共有500条查询结果,搜索用时 15 毫秒
1.
Louis R. D'Abramo Cortney L. Ohs Kathleen C. E. Elgarico 《Journal of the World Aquaculture Society》2006,37(3):307-312
The effects of addition of substrate consisting of plastic mesh fencing to experimental earthen ponds were evaluated for the culture of the red swamp crawfish, Procambarus clarkii, without planted forage. Mean daily yield (kg/ha/d), number of crawfish harvested (number/ha/d), and mean individual harvest weight were compared for ponds with and without substrate during a 2‐yr period. The surface area of added substrate was equivalent to 50% of the bottom surface area of the pond. Mean daily yield in the ponds containing substrate, based on a comparison with that of the previous year, increased by 80.2% and was principally attributed to a 66.7% increase in the number of crawfish harvested. Comparative values for the ponds without substrate were ?13.1 and ?11.7%. For the second year, the treatment‐dependent response was consistent. Mean daily yield for the substrate ponds increased by 48.8% compared to 15.0% for the ponds lacking substrate. The primary benefit of the substrate appears to be provision of refuge and three‐dimensional distribution of crawfish in the pond, thereby reducing the incidence of cannibalism and increasing the total number of crawfish harvested per hectare per day. The benefit of the substrate in a commercial production setting must be weighed against its cost and longevity as well as the conditions of the particular management scenario into which it may be incorporated. 相似文献
2.
David E. Anderson Peter D. Constable Kathleen E. Yvorchuk Neil V. Anderson Guy St-Jean Linda Rock 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1994,8(3):207-211
An alpaca and a llama in late stages of gestation were evaluated for lethargy, anorexia, and recumbency. Both camelids had cloudy, white, turbid serum, elevated serum triglyceride (1564, 5658 mg/dL, respectively) and cholesterol (158, 297 mg/dL, respectively) concentrations, and ketonuria. Signs of fetal stress were evident ultrasonographically in the alpaca, and a live cria was delivered by Cesarean section performed under general anesthesia. The alpaca developed severe metabolic acidosis, hepatic lipidosis, and acute renal failure secondary to renal lipidosis and died 36 hours after admission despite medical therapy. Histopathology revealed renal and hepatic lipidosis and neutrophilic pancreatitis. The cria died 72 hours after birth. The llama responded to IV electrolyte, dextrose, and regular crystalline insulin therapy. The pregnancy was maintained, and the llama was discharged from the hospital 20 days after admission. Two months after discharge, the llama gave birth to a live, 5 kg cria. Findings of hypertriglyceridemia, hypercholesterolemia, elevated sorbitol dehydrogenase activity, metabolic acidosis, azotemia, and ketonuria occurred in these two camelids. Based on this report, camelids appear to be similar to both horses and cattle in their response to severe energy imbalances in late gestation. 相似文献
3.
M P Nasisse M G Davidson N J MacLachlan W Corbett L P Tate H C Newman E M Hardie 《American journal of veterinary research》1988,49(11):1972-1978
Using a hand-held optical fiber, a surgical neodymium:yttrium, aluminum, and garnet laser was used transsclerally on the left ciliary body of 25 dogs. Dogs were assigned to groups and were given low (100 J) and high (238 J) energy levels. In 12 dogs given 100-J energy, the intraocular pressure decreased a mean value of 6 mm of Hg below that in the untreated right eye. However, intraocular pressure returned to the pretreatment value 1 week after treatment. Intraocular lesions were not found by histologic examination 28 days later. In the second group of 13 dogs treated with 238-J energy, 6 were euthanatized 7 days after treatment and 7 were euthanatized 28 days after treatment. A mean decrease in intraocular pressure of 10 mm of Hg in the treated left eye, relative to the untreated right eye, persisted throughout the evaluation period. In eyes examined histologically 7 days after treatment, ciliary hemorrhage and necrosis were prominent. Other histologic changes were minimal and consisted principally of iris stromal hemorrhage. Of 7 dogs examined for 28 days after treatment, 6 remained sighted; in 1 dog, extensive intraocular hemorrhage occurred, eventually resulting in phthisis bulbi. Ciliary atrophy and fibrosis were the important histologic lesions observed 28 days after treatment. Laser energy delivered transsclerally by this optical system effectively induced ciliary necrosis and may be an effective treatment for canine glaucoma. 相似文献
4.
5.
Burns GA Ruby KL Debowes RM Seaman SJ Brannan JK 《Journal of veterinary medical education》2006,33(2):301-308
Data from focused studies and comprehensive surveys suggest that developing or enhancing non-technical (professional) skills will result in a more satisfied and successful veterinary student or veterinary graduate. The College of Veterinary Medicine at Washington State University has devoted considerable time, effort, and resources to augmenting the non-technical aspects of its curriculum while maintaining the traditional strengths of its DVM program. Here we summarize pertinent research and best-practice recommendations from a variety of sources and outline the steps that have been taken, with the underlying rationales, to integrate the teaching and modeling of non-technical (professional) competence throughout a four-year course of veterinary study. 相似文献
6.
Western blot analysis showed that sweat gland cells from freely sweating horses expressed the water channel aquaporin-5 (AQP-5). Immunohistochemistry revealed a strong AQP-5-like activity reaction at the apical membrane of the glandular secretory cells, which was absent from the surrounding myoepithelium and all other skin structures. In anhidrotic horses, AQP-5 was also found at the apical membrane of the luminal sweat gland cells, but the level of expression reduced with the length of time that the animal had displayed anhidrosis. The level of AQP-5 expression was substantially reduced in animals with long-term anhidrosis, hence implicating water channel impairment as a possible factor in the development of this disorder. 相似文献
7.
8.
Hiroto Yoshikawa Monique N. Mayer Kathleen A. Linn Ryan M. Dickinson Anthony P. Carr 《The Canadian veterinary journal. La revue veterinaire canadienne》2008,49(9):877-879
An 8-year-old, castrated male golden retriever was referred for lethargy and inappetance. Severe pain was elicited on palpation of the left temporomandibular joint region. Computed tomography revealed aggressive bone destruction of the left bulla. Squamous cell carcinoma was diagnosed. Malignant tumor in the canine middle ear is rare. 相似文献
9.
Mary E. Gordon PhD Michael L. Jerina BS Randel H. Raub PhD Karen E. Davison PhD J. Kathleen Young PhD 《Journal of Equine Veterinary Science》2008,28(5):289-294
This study tested the hypothesis that feeding an identically formulated, low sugar and starch concentrate in three forms (5-mm extruded [E], 4-mm pellet [P], and 19-mm oval [O]) would affect consumption rate and glucose or insulin responses, or both. Horses received 1.8 kg treatment feed in a randomized, crossover design, with samples taken every 30 minutes for 6 hours for blood glucose and insulin response. Pearson's correlation compared consumption time, insulin and glucose peak, and time to peak insulin and glucose. The pellet (P) elicited a lower (P = .01) glucose concentration at 2.5 hours than O. The pellet also elicited a lower (P = .03) insulin concentration at 5.5 hours than E and O. There were no differences (P > .05) in area under the curve (AUC) insulin, peak insulin, and time to peak insulin for the three treatments. Average insulin concentration was lower (P = .01) for P versus O. There were no differences (P > .05) in average insulin between P and E, nor between O and E. There were no differences (P > .05) in AUC and peak glucose concentration. Time to peak glucose was longer (P = .04) for P versus E. Average glucose concentration was lower (P = .02) for P versus O. Consumption time was longer (P = .03) for O versus P. There was a positive correlation between consumption time and time to peak insulin (r = 0.46, P = .029). Further research on feeding practices, feed forms, and consumption times that affect glycemic response is necessary. 相似文献
10.
Jiaying Ng Kathleen A. Linn Cindy L. Shmon Sarah Parker Lesley A. Zwicker 《Veterinary radiology & ultrasound》2020,61(2):130-136
Nontraumatic spontaneous pneumoperitoneum suggests the presence of gastrointestinal perforation; early detection can be lifesaving. Horizontal beam projections have been reported to be more sensitive than standard radiographic views for detecting small volumes of free peritoneal gas. This prospective, experimental, analytical study compared both left lateral (LL) and ventrodorsal (VD) standard views to horizontal beam projections for detecting small volumes of artificially induced pneumoperitoneum in live dogs. The effect of radiology training on accurate detection of small amounts of free peritoneal air was also assessed. Fourteen dogs had four radiographic projections taken after injection of 0, 2.5, 5, and 10 mL of cumulative air into their abdominal cavities. Radiographs were interpreted individually by three American College of Veterinary Radiology‐certified radiologists and three small animal internship‐trained veterinarians who were blinded to the air volume injected. At 2.5 and 10 mL of air injected, the LL projection had highest odds of an accurate response (odds ratio [OR] = 2.4 and 99.0 when compared to VD horizontal and VD projections, respectively). At 5 mL of air injected, the lateral horizontal (LH) projection had the highest odds of an accurate response (OR = 3.2 compared to VD horizontal). The LL projection was not significantly different from the LH projection at all volumes of air injected. Board certification led to higher odds of accurate responses at volumes of 5 (OR = 2.2) and 10 mL (OR = 3.6), as compared to nonspecialist veterinarians. Overall, LH and standard LL appeared to be the most useful radiographic projections for detection of small amounts of free peritoneal gas. 相似文献