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51.
Brian J. Brecka Christopher C. Kohler David H. Wahl 《Journal of the World Aquaculture Society》1995,26(4):416-425
Growth rate, survival and body composition of muskellunge Esox musquinongy (initial mean total length = 125 mm) and tiger muskellunge E. masquinongy × E. lucius (initial mean total length = 115 mm) fed semi-purified diets differing in protein level from 31 to 40% and 34 to 45%, respectively, were evaluated in 8-wk trials. The minimum protein level that yielded satisfactory growth rates for muskellunge was 37%, whereas tiger muskellunge growth rates were highest for fish fed a 45% protein diet. Growth differences were caused by changes in protein quantity, not quality, as amino acid ratios were similar for test diets and showed no imbalances among diets. Condition factors for both fishes increased with dietary protein. Survival of muskellunge (73%) and tiger muskellunge (97%) was not pffected by diet type. Body protein increased and fat content decreased in both fishes when fed higher dietary protein. Results suggest that both fishes respond similarly to dietary changes, but that substantial differences exist in protein requirements. 相似文献
52.
Jeffrey L. Beynon David L. Hutchins Anthony J. Rubino Addison L. Lawrence Brian R. Chapman 《Journal of the World Aquaculture Society》1981,12(2):63-70
Birds can reduce production of shrimp in mariculture grow-out ponds through predation and competition for feed. This study involved weekly nocturnal enumeration of bird populations and observation of nocturnal avian habits on a series of 0.1 ha experimental ponds at the Texas A&M University Shrimp Mariculture Facility at Corpus Christi, Texas. Observations were conducted hourly from sunset to sunrise during October through December 1980. The rate of predation was evaluated every three hours by comparing the number of feeding attempts to the number of successful prey captures over a known time period. Gulls (Family Laridae) acted primarily as competitors for feed. Active feeding by gulls was restricted to daylight hours, consequently feed loss decreased when the feed was distributed at or after dusk. Major preadatory birds included herons and egrets (F. Ardeidae), migratory ducks (F. Anatidae), and, to a lesser extent, grebes (F. Podicipedidae) and shorebirds (Order Charadriiformes). Bird predation decreased pond production by 75% in some ponds. 相似文献
53.
Gilger BC Pizzirani S Johnston LC Urdiales NR 《Journal of the American Veterinary Medical Association》2003,222(3):343-5, 316
A hydroxyapatite orbital implant was used after enucleation of an eye from a 5-year-old performance horse. A custom-made corneoscleral prosthesis was made and fitted over the hydroxyapatite implant. The implant and surgery were well tolerated. Placement of a cosmetic prosthesis is desired after enucleation of equine eyes to allow horses to return to competition. Synthetic spheres consisting of methylmethacrylate or silicone have been used, although reported complications have included extrusion, infection, and poor cosmetic results. Hydroxyapatite orbital implants made from marine coral allow vascular and fibrous tissue growth from the host orbit into the implant, which decreases the possibility of implant extrusion or infection and allows enhanced healing of defects in the overlying conjunctiva. Extraocular muscle fixation onto the implant permits motility and assists in the prevention of implant extrusion. 相似文献
54.
Michau TM Gilger BC Maggio F Davidson MG 《Journal of the American Veterinary Medical Association》2003,222(5):607-612
OBJECTIVE: To evaluate the outcome of thermokeratoplasty for treatment of ulcerative keratitis and bullous keratopathy secondary to corneal endothelial disease in dogs. DESIGN: Retrospective study. ANIMALS: 13 dogs. PROCEDURES: Medical records from 1994 to 2001 for dogs evaluated because of ulcerative keratitis and bullous keratopathy and treated with thermokeratoplasty were reviewed. RESULTS: There were 7 spayed females, 5 castrated males, and 1 sexually intact male, ranging from 6 to 16 years of age. Ten dogs had endothelial degeneration, and 3 dogs had breed-related endothelial dystrophy. All dogs had bullous keratopathy, characterized by microbullae formation that was detected via biomicroscopy. Recurrent or nonhealing corneal ulcers were detected unilaterally in 5 dogs and bilaterally in 8 dogs. Mean +/- SD duration from thermokeratoplasty until ulcerations were healed for all dogs was 2.2 +/- 1.1 weeks. All dogs that underwent thermokeratoplasty for nonhealing corneal ulceration secondary to endothelial disease and corneal edema had epithelial wound healing and resolution of corneal ulceration. Mean duration of treatment (ie, topical treatment required until resolution of ulceration) was significantly less after thermokeratoplasty than duration of treatment (with multiple treatments) prior to referral. CONCLUSIONS AND CLINICAL RELEVANCE: It may be necessary to perform thermokeratoplasty of the entire cornea to prevent recurrence of ulcerations in areas that have not been treated with thermokeratoplasty. 相似文献
55.
Immunogenicity of bovine parainfluenza type 3 virus proteins encapsulated in nanoparticle vaccines,following intranasal administration to mice 总被引:2,自引:0,他引:2
Shephard MJ Todd D Adair BM Po AL Mackie DP Scott EM 《Research in veterinary science》2003,74(2):187-190
Stimulation of long lasting, protective immunity to respiratory viruses is often difficult to achieve with conventional respiratory vaccines. Polymeric nanoparticles, incorporating viral proteins have been shown to offer sustained release of antigen, with consequent prolongued stimulation of the respiratory immune system. In this paper the efficacy of two nanoparticle vaccines (poly-lactide-co-glycolide, PLGA; polymethylmethacrylate, PMMA), incorporating proteins of bovine parainfluenza type 3 virus (BPI-3) was investigated. As a preliminary to experiments in calves, it was considered essential to demonstrate immunogenicity of the experimental vaccine in mice. Mice immunised with PLGA nanoparticles, containing BPI-3 proteins, developed higher levels of virus-specific antibody than mice immunised with the PMMA vaccine or with soluble viral proteins alone. Immunoblotting using serum from the vaccinated mice, demonstrated strong reactions against the major BPI-3 proteins. 相似文献
56.
Pulmonary embolism associated with canine total hip replacement 总被引:4,自引:0,他引:4
OBJECTIVE: To determine by pulmonary perfusion scans and ultrasonography if embolemia occurs during total hip replacement (THR) surgery in dogs. STUDY DESIGN: Prospective clinical study. ANIMALS: Forty client-owned dogs that had THR surgery. METHODS: Thoracic radiographs were taken immediately after THR and immediately after completion of (99m)Tc-MAA lung scans. Scintigraphy was performed in 28 dogs, 48 hours after THR. Intraoperative ultrasonography (intercostal or transesophageal) was performed in another 12 dogs that had THR. The right atrium and ventricle and pulmonary outflow tract were observed during and for 5 to 8 minutes after femoral component insertion into medullary canals prepared by reaming, and lavage and aspiration of debris before filling with polymethylmethacrylate in dough stage. A modified Prospective Investigation of Pulmonary Embolism Diagnosis (PIOPED) classification system was used to evaluate lung scans. RESULTS: No pulmonary radiographic abnormalities were identified. Segmental and subsegmental perfusion defects occurred in 23 (82%) dogs and were classified as severe in 9 (32%) dogs, moderate in 11, and mild in 3. There was no particular lobe predilection. Patchy mulberry-appearing defects, indicative of fat embolism, were most common. Embolemia was observed by ultrasound in 10 dogs. Variable-sized particles occurred in 8 dogs, particles and bubbles in 2 dogs, and no emboli were observed in 2 dogs. Embolemia was observed within 10 seconds after femoral stem insertion and lasted < 1 minute. Pneumoemboli remained in the right atrium for > 8 minutes before dislodgement. CONCLUSIONS: Embolemia of either air, particles, or both occurs in most dogs during THR surgery. CLINICAL RELEVANCE: Most dogs seemingly spontaneously recover from pulmonary embolism that occurs during THR. The risk of clinical complications from this pulmonary embolism should be taken seriously, even though the exact morbidity and mortality rates are unknown. 相似文献
57.
58.
A 3-year-old-female, spayed Golden Retriever was examined for a unilateral retinal detachment with exophthalmos. Ultrasonographically, a mass was detected with intra- and extraocular extension. The orbit was exenterated and the dog recovered uneventfully. Histopathologic diagnosis was a primary choroidal melanoma with orbital extension, however, the behavioral and cytologic features were benign. Routine examinations postsurgically were nonremarkable. Twenty-one months after surgery the dog was euthanized for respiratory collapse with radiographic signs of metastasis. Necropsy revealed black lesions in the lung and liver. Histopathologic diagnosis was metastatic melanoma with morphology and behavior identical to the primary choroidal melanoma. This is the first definitive case of a canine choroidal melanoma with metastasis. 相似文献
59.
Brian J McCluskey Brandy Burgess James Glover Hailu Kinde Sharon Hietala 《Journal of veterinary diagnostic investigation》2006,18(3):296-299
The use of sentinel chickens in establishing the negative status of commercial poultry flocks depopulated due to exotic Newcastle disease (END) is considered to be an economically beneficial process. However, the costs and benefits of using sentinel chickens in noncommercial operations are in question. The objective of this study was to use sentinel chickens to evaluate whether adequate cleaning and disinfection coupled with an appropriate time period without susceptible poultry species on the premises would eliminate END virus from a noncommercial poultry operation and preclude the need for placement of sentinels in previously infected operations before declaring them free of virus. Noncommercial poultry operations were selected from the 2002 to 2003 END outbreak database. Operations included in the study had one or more isolations of END virus (ENDV) from cloacal or oropharyngeal swabs of birds on the premises. A total of 546 birds were placed on 53 premises. All sentinel birds sampled after placements were negative by virus detection methods and serologic tests. Results of this study indicate that time and the application of appropriate cleaning and disinfection procedures will adequately mitigate the risk of viable virus persisting in noncommercial poultry operations. In the future, this information may eliminate the need for sentinel bird placement to ensure virus free status of premises before repopulation, thereby decreasing the costs of END eradication. 相似文献
60.
Companion planting of Cleome gynandra, of Kenyan origin, in beds of cut-flower roses reduces significantly red spider mite (Tetranychus urticae Koch) infestation without any detrimental effect on productivity or flower quality. The level of reduction is dependent upon the density of the C. gynandra plants with 15 plants in a 1.8 m2 bed (8.3 plants m2) being the most effective, planted either around the bed perimeter or within the rows of roses. The relatively high density of C. gynandra plants required may limit the direct application of this technology in export-focused, greenhouse rose production yet may be of significant value as a supplement to other mite-control strategies. The potential benefits of such companion planting for growers of field roses and those involved in some domestic markets are also evident. Research into the nature and extraction of the active, volatile mite-repellant components of C. gynandra is indicated. 相似文献