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Fasciolosis is an endemic zoonotic parasitic disease with significant impacts on human health and both animal health and production. Early post-infection impacts on the host remain unclear. The objective of this study was to determine the changes, if any, to levels of endotoxin in cattle plasma in response to early-stage infection with Fasciola hepatica. Thirty-six (36) commercial bred cattle were experimentally infected with approximately 400 viable metacercariae. Plasma lipopolysaccharide (endotoxin) levels were examined on 24 occasions from 0 h before infection to 336 h after infection using the Limulus Amoebocyte Lysate chromogenic end point assay and compared with that of six (6) uninfected control animals. Peak lipopolysaccharide levels in infected animals were reached at 52 h after infection and returned to pre-infection levels at time 144 h after infection. Infected animals had significantly elevated lipopolysaccharide levels between 24 and 120 h after infection when compared to uninfected animals. The mean change in endotoxin units (EU)/mL over time after infection was statistically significant in infected animals. Elevations of lipopolysaccharide occurred in all infected animals suggesting a possible repeatable and titratable endotoxemia conducive to therapeutic agent model development. 相似文献
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Roger W. Doyle Somsuk Singholka Michael B. New 《Aquaculture (Amsterdam, Netherlands)》1983,30(1-4):237-247
“Indirect selection” is exerted on a trait indirectly, by means other than artificial selection for the trait itself. Expressions are derived for calculating the intensity of indirect selection in aquaculture environments. The calculations are illustrated with growth-rate data on M. rosenbergii from farm ponds in Thailand, and with computer-generated data which simulate measurements made during a multiple mark-recapture experiment. Indirect selection for growth is probably negligible in Thai prawn farms and hatcheries at present, but small changes in management practice could exert strong indirect selection on growth rate. One very effective change appears to be collecting broodstock as early in the production cycle as possible. Control of indirect selection may be useful for the genetic improvement of aquaculture stock, especially in developing countries and other situations where an intensive artificial selection program is not economically or biologically desirable. Like all selection programs, the probability of success is critically dependent on the genetics of the traits being selected. 相似文献
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Adin CA Herrgesell EJ Nyland TG Hughes JM Gregory CR Kyles AE Cowgill LD Ling GV 《Journal of the American Veterinary Medical Association》2003,222(11):1576-1581
OBJECTIVE: o determine sensitivity and specificity of radiography, ultrasonography, and antegrade pyelography for detection of ureteral obstructions in cats. DESIGN: Retrospective study. ANIMALS: 11 cats. PROCEDURE: Medical records of cats that had radiography, ultrasonography, and antegrade pyelography performed for suspected ureteral obstructions were examined. Ultrasound-guided pyelocentesis and fluoroscopic-assisted antegrade pyelography were performed on 18 kidneys in 11 cats. Obstructive ureteral lesions were confirmed in all cats by surgical or necropsy examination. Sensitivity and specificity of survey radiography, ultrasonography, and antegrade pyelography for identification of ureteral obstructions were calculated. Surgical or necropsy findings were used as the standard for comparison. RESULTS: All cats were azotemic. Mean +/- SD serum creatinine and BUN concentrations were 10.2 +/- 6.1 and 149 +/- 82 mg/dL, respectively. Fifteen of 18 ureters were found to be obstructed at surgery or necropsy. Sensitivity and specificity were 60 and 100% for radiography and 100 and 33% for ultrasonography, respectively, in identification of ureteral obstructions. Leakage of contrast material developed in 8 of 18 kidneys during antegrade pyelography and prevented diagnostic interpretation in 5 of 18 studies. For the 13 diagnostic studies, specificity and sensitivity were 100% by use of the antegrade pyelography technique. Correct identification of the anatomic location of the ureteral obstruction was obtained in 100% of diagnostic antegrade pyelography studies and in 60% of radiography or ultrasonography studies. CONCLUSIONS AND CLINICAL RELEVANCE: Antegrade pyelography can be a useful alternative in the diagnosis and localization of ureteral obstructions in azotemic cats, although leakage of contrast material may prevent interpretation of the study. 相似文献
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Kyles AE Hardie EM Mehl M Gregory CR 《Journal of the American Veterinary Medical Association》2002,220(9):1341-1347
OBJECTIVE: To document the signalment; history; clinical signs; clinicopathologic, diagnostic imaging, and surgical findings; perioperative complications; and long-term clinical results of ameroid ring constrictor (ARC) placement on single extrahepatic portosystemic shunts (PSS) in cats. DESIGN: Retrospective study. ANIMALS: 23 cats treated with an ARC on a single extrahepatic PSS. PROCEDURE: An ARC was placed surgically around the PSS. Portal pressure was measured prior to ARC placement, with complete temporary PSS occlusion, and after ARC placement. Cats were scheduled for recheck transcolonic portal scintigraphy 8 to 10 weeks after surgery. Follow-up information was obtained by telephone interview with the owners. RESULTS: An ARC was successfully placed in 22 of 23 cats. Intraoperative complications, consisting of PSS hemorrhage, occurred in 2 cats. Mean (+/- SD) portal pressure (n = 15) was 6.7+/-2.9 mm Hg before PSS manipulation, 18.6+/-7.7 mm Hg with complete temporary PSS occlusion, and 6.9+/-2.7 mm Hg after ARC placement. Postoperative complications developed in 77% (17 of 22) of cats after ARC placement, and included central blindness, hyperthermia, frantic behavior, and generalized motor seizures. Perioperative mortality rate was 4.3% (1 of 23). Persistent shunting was identified in 8 of 14 cats. Overall, 75% (15 of 20) of cats had an excellent long-term outcome. CONCLUSIONS AND CLINICAL RELEVANCE: Placement of an ARC on single extrahepatic PSS in cats resulted in low surgical complication and perioperative mortality rates, but most cats did have substantial postoperative complications. Persistent shunting was common, although many cats with persistent shunting were clinically normal. 相似文献
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B Keeley M Glyde S Guerin R Doyle 《Veterinary and comparative orthopaedics and traumatology》2007,20(3):198-203
Multiple ligament injuries of the canine and feline stifle joint which result in luxation are uncommon. Two cats and one dog, that had sustained such a joint injury were surgically treated. A rupture of the cranial and caudal cruciate ligaments, and at least one collateral ligament was observed in all of the three animals. Prosthetic reconstruction was used, as previously described, in combination with a novel technique of intraoperative placement of a temporary trans-articular pin (TTP) to maintain intra-operative anatomical reduction. TTP placement facilitated maintenance of joint alignment during surgical reconstruction and aided appropriate tensioning of the prosthetic sutures, preventing collapse of femorotibial joint compartments. The TTP was removed prior to closure of the joint allowing immediate post-operative joint mobilisation. Based on assessment by their owners, all the animals made a complete recovery. TTP was considered a relatively simple and effective adjunctive aid for surgical treatment of traumatic luxation of the stifle joint. 相似文献