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141.
Shawn D. Coyle Siddhartha Dasgupta James H. Tidwell Thomas Beavers Leigh Anne Bright David K. Yasharian 《Journal of the World Aquaculture Society》2005,36(3):282-290
Abstract— The freshwater prawn Macrobrachiurn rosenbergii is a commercially important culture species in the South Central United States. Two major constraints in the commercial culture of the freshwater prawn in the U.S. are poor survival during live transportation of seed‐stock to growout ponds, and live transportation of pond harvested prawn to distant live markets due to the territorial and cannibalistic nature of prawn. The use of anesthetics could possibly improve transport survival; however, to date anesthetic agents have not been evaluated for use with prawn. Two trials were conducted with juvenile freshwater prawn to compare the efficacy of anesthetics commonly used on fish. The first trial was designed to identify the most promising candidates. In Study 1, tricaine methanesulfonate (MS‐222), 2‐phenoxyethanol, quinaldine sulfate (quinaldine), clove oil, and Aqui‐STM were evaluated at 25 and 100 mg/L for 1 h in three replicate 10‐L glass containers, containing five juvenile prawn each. Relative sedation level was determined every 3 min for 1 h, then recovery time and survival were measured. In Study 1, MS‐222 and 2‐phenoxyethanol were determined to be ineffective on prawn at all rates tested. Based on their performance in Study 1, quinaldine, clove oil, and AquiSTM were evaluated at 100, 200, and 300 mg/L in Study 2. Observations were determined as in Study 1. Clove oil and Aqui‐STM induced anesthesia faster and at lower concentrations than quinaldine. At the highest treatment rate (300 mg/L) prawn suffered 60% mortality in the Aqui‐STM treatment, 13% mortality in the quinaldine treatment, and 0% mortality in the clove oil treatment and control following a 1‐h exposure to these concentrations. Based on these data, Aqui‐STM and clove oil applied at 100 mg/L may be suitable anesthetic treatments for prawn. Additional research is needed to determine optimal time and dose relationships to minimize stress during holding, handling, and transportation of prawn. 相似文献
142.
143.
Anne Peaston BVSc 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1993,7(1):44-45
This 12-month-old, outdoor intact male cat (Fig. 1) was examined because of an untreated draining nasal lesion. The lesion. initially appeared as small punctures, and progressed ovcr 2 months to an ulcerated draining nodule that gradually enlarged to involve the whole muzzle, extending bilaterally to the medial canthi and having multiple drainage points through overlying necrotic skin. Results of serum feline leukemia virus antigen and feline immunodeficiency virus antibody tests were negative. 相似文献
144.
Gordon Swaine Robert J. Corcoran Anne E. Cranny Marguerite A. Davey 《Pest management science》1980,11(5):467-470
Fruit packed in fibreboard cartons required a higher dosage of 1,2-dibromoethane (EBD) for an effective commodity treatment than fruit packed in polystyrene trays. This was due to considerably greater sorption of EDB by fibreboard compared with polystyrene, as indicated by concentration-time products. However, compensating factors in the form of a lower sorption of EDB by the fruit itself when in fibreboard cartons, and a residual fumigant effect for fruit in such cartons, reduced the expected increase in dosage requirement. The required dosages of EDB for effective treatments were 20 g m?3 in fibreboard cartons and 16 g m?3 in polystyrene trays, for 2 h at 20°C. 相似文献
145.
146.
Ivar V gsholm Hans Olav Djupvik Finn Victor Willumsen Anne Marie Tveit Karl Tangen 《Preventive veterinary medicine》1994,19(3-4):277-290
A case-control study is reported of 57 holdings (holdings in which salmon are raised in sea-water) with infectious salmon anaemia (ISA) and 61 holdings without ISA, together with a follow-up study of the control holdings, during 1988–1990. Generally the identified risk factors implied poor biosecurity since passive transmission (proximity to other ISA holdings) and active transmission (management practices which increased exposure to foreign biological material) were found to be major risk factors. The findings indicated that ISA was spread by infected live salmon or infected biological material i.e. animal waste or discharge from normal operations and slaughter. The findings also indicated that decreased host resistance could be important, but these results could be also be explained by a misclassification bias. Moreover, the findings indicate that a prompt eradication policy and improved biosecurity would be important means of controlling ISA. 相似文献
147.
148.
T. J. McClure B.V.Sc. Ph.D. Anne E. Dowell N.D.D. 《Australian veterinary journal》1968,44(12):536-542
149.
Graves TK Barger AM Adams B Krockenberger MB 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2005,34(4):409-412
A 3-year-old Boxer was presented with progressive diarrhea, vomiting, and lethargy of 5-months duration. The dog had watery black feces, a mature neutrophilia, and microcytic anemia. Cytologic evaluation of a direct fecal smear stained with Wright's-Giemsa revealed numerous encapsulated, narrow-based, budding organisms consistent with Cryptococcus sp. Pyogranulomatous inflammation and Cryptococcus organisms also were observed in ultrasound-guided fine-needle aspirates of the small intestine and mesenteric lymph nodes, and in histologic sections of colonic biopsies obtained by endoscopy. Multifocal chorioretinitis by fundic examination was consistent with systemic mycosis, and the reciprocal antigen titer (1600) on a cryptococcal antigen latex agglutination test for Cryptococcus neoformans was markedly increased. Using immunohistochemistry, the organism was identified further as C neoformans var. grubii (C neoformans var. neoformans serotype A). After 3 weeks of antifungal treatment, ultrasound examination revealed urinary bladder wall thickening, and Cryptococcus organisms were found in a urine sediment preparation. After 4 months of treatment, the dog was clinically normal and had no abnormal findings on CBC, serum biochemistry, urinalysis, or fecal cytology; however, the antigen titer remained unchanged, mesenteric lymphadenomegaly and jejunal wall thickening were still evident, and cytologic evaluation of fine-needles aspirates of the jejunal wall revealed budding Cryptococcus organisms. Intestinal involvement in dogs with cryptococcosis is rare, and diagnosis by fecal cytology has not been documented previously. 相似文献
150.