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Canine parvovirus (CPV) and canine distemper virus (CDV) infections are relatively common in animal shelters and are important population management issues since the immune status of incoming dogs is usually unknown. This study aimed to determine the prevalence of positive antibody test results for CPV and CDV in incoming dogs aged ≥ 4 months and to measure antibody response over 2 weeks following vaccination with a modified live vaccine (MLV). Dogs aged 4-24 months entering an adoption-guarantee shelter (Shelter 1, n=51) and aged ≥ 4 months entering a limited admission shelter (Shelter 2; n=51) were enrolled. Dogs from Shelter 1 had been vaccinated with MLV at a municipal shelter 5 days before enrollment, whereas dogs from Shelter 2 had no known history of vaccination at enrollment. Sera were obtained on day 1, immediately prior to CPV/CDV MLV, and tested using an in-clinic ELISA kit to detect CPV/CDV antibodies. Dogs negative for CPV and/or CDV were retested at day 6-8 and those dogs still negative at day 6-8 were retested at day 13-15. Prior to CPV/CDV MLV on day 1, more dogs tested positive for CPV (Shelter 1 - 68.6%; Shelter 2 - 84.3%) than for CDV (Shelter 1 - 37.3%; Shelter 2 - 41.2%). On day 1, prior to MLV, all spayed/neutered animals tested CPV antibody-positive (n=17/102) and CPV antibody-positive dogs were older than serologically negative dogs (Shelter 1, P=0.0029; Shelter 2, P=0.0042). By day 13-15, almost all dogs were CPV antibody-positive (Shelter 1 - 97.9%; Shelter 2 - 100.0%) and CDV antibody-positive (Shelter 1 - 93.8%; Shelter 2 - 97.8%). MLV induces protective antibody titers against CPV/CDV in almost all dogs after 13-15 days.  相似文献   
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Objective-To characterize duodenal sigmoid flexure volvulus (DSFV) and determine the prognosis for affected cattle undergoing surgery. Design-Retrospective case series. Animals-29 dairy cattle. Procedures-The medical records were analyzed for history, signalment, clinical signs, medical management, surgical findings, and outcome. Results-29 cattle were determined to have DSFV between December 2006 and August 2010. Twenty cattle had had an omentopexy or pyloropexy performed 1 day to 2 years before initial evaluation. Cattle were afebrile, tachycardic, and moderately dehydrated, with a small zone of percussion with a ping at the 10th to 12th right intercostal spaces and associated succussion. Biochemical changes were a severe hypokalemic (mean ± SD, 2.9 ± 0.5 mmol/L; median, 3.1 mmol/L; range, 2.08 to 3.92 mmol/L), hypochloremic (mean, 69.7 ± 11.1 mmol/L; median, 71.7 mmol/L; range, 49.1 to 94.1 mmol/L) metabolic alkalosis (mean total CO(2), 44.5 ± 7.4 mmol/L; median, 45.3 mmol/L; range, 31.5 to 59.6 mmol/L) and hyperbilirubinemia (mean, 32.4 ± 29.0 μmol/L; median, 20.5 μmol/L; range, 7.8 to 107 μmol/L). Surgical findings for DSFV included an empty descending duodenum adjacent to a dorsally displaced and dilated cranial segment of the duodenum, distended abomasum and gallbladder, and a tight volvulus at the base of the duodenal sigmoid flexure. Manual reduction was considered successful if the descending duodenum filled after cranial duodenal massage. Twenty-two patients were successfully treated; the remaining 7 died or were euthanized within 4 days after surgery. Conclusions and Clinical Relevance-A condition clinically resembling abomasal volvulus but affecting the duodenal sigmoid flexure has been recognized in dairy cattle. When a focal, dorsal right-sided ping and succussion are present combined with severe hypokalemic, hypochloremic metabolic alkalosis and high bilirubin concentration, DSFV should be suspected, especially when there is a history of prior abomasal fixation. After surgical correction, the prognosis is fair to good.  相似文献   
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An ultrasonographic approach for the tympanic bulla in calves is described. Ultrasound evaluation was performed through a lateral approach on 7 fetuses, 2 newborn calves, and 4 living calves of various ages. The probe was positioned caudal to the vertical mandibular ramus, ventral to the base of the ear. Three different positions of the probe were used. The tympanic bulla and adjacent structures were successfully identified and their ultrasonographic appearance described. Fluid within the tympanic bulla was visualized in 12 bullae in the cadavers and in 6 bullae in live calves. Ultrasound imaging has been shown to be useful but its diagnostic value remains to be studied in clinical cases of otitis media in calves.  相似文献   
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The correct measurement of spermatic concentration in boar semen is one of the basic tasks routinely performed at the Swine Artificial Insemination Center (CIAS). This article explains two experiments whose objectives were: Experiment 1: This trial had two objectives: (1) to evaluate the precision of the spermdensimeter (SPM) with relation to the Neubauer count chamber (CN) which is considered the standard technique in the field and (2) to correct the scale on the SPM table. Experiment 2: This trial also had two objectives: (1) to evaluate the time and repetitions required in the SPM and (2) to compare the SPM adjusted table produced in Expt 1 with the SPM standard table. The methods in Expt 1 were used to measure total spermatic concentration in 141 boar ejaculates. The average spermatic concentrations (10(6) spermatozoids/ml) and average dose number were 229.1 and 22.6 for CN, and 283.6 and 28.0 for SPM. These results indicate that the SPM has a tendency to overestimate spermatic concentration with relation to the CN. The SPM produced a smaller coefficient of variation and needed lesser examination time than the CN (p < 0.05). The SPM adjusted table created in Expt 1 produced similar results as the SPM and CN standard tables (2.96 billion live spermatozoids/dose vs 2.36 billion live spermatozoids/dose). Incorporation and evaluation of supplemental data from other CIAS regarding the use of the SPM adjusted table in the field entitled 'Adjusted Table for Karras Spermdensimeter LPS-FMVZ-USP' would be valuable to prove its efficiency.  相似文献   
227.
Concentrations of serum thyroxine (T4) and 3,3',5-triiodothyronine (T3) were determined in 7 clinically healthy adult dogs before and after administration of freshly reconstituted thyrotropin (TSH) and TSH that had been previously reconstituted and frozen for 1, 2, and 3 months. The 4 TSH response tests were performed at 30-day intervals by collecting blood samples for serum T4 and T3 determinations before and 4 and 6 hours after IV administration of TSH (0.1 U/kg of body weight). Baseline serum concentrations of T4 and T3 were similar at each of the 4 sample collection times over the 3-month period of the study. Mean serum concentrations of T4 and T3 increased significantly (P less than 0.01) over baseline values after administration of freshly reconstituted TSH or TSH that had been previously frozen for 1, 2, or 3 months. Significant difference was not found in the mean post-TSH serum T4 or T3 concentration after injection of freshly reconstituted TSH or TSH that had been previously frozen for 1, 2, or 3 months. In 2 of the 7 dogs, mild reactions--mild ataxia and weakness--were observed during the last of the series of TSH response tests (ie, after IV administration of TSH that had been previously frozen for 3 months). Results of this study suggest that for use in dogs, reconstituted TSH stored at -20 C maintains adequate biological activity for at least 3 months. The ability to store reconstituted TSH for a longer period than the recommended 48 hours represents an economic advantage, because it allows clinicians to perform more TSH response tests per vial of TSH.  相似文献   
228.
The reciprocal yield/density equation 1w = α + β? (when w is the mean weight per plant, or plant part, at density ?, and α and β are constants when ? is the only variable) was used to interpret the results of two plant density experiments with populations ranging from 15–280 plants/m2. In a fertilizer experiment the level of fertilizer used had a major effect on the β parameter, while the α parameter was influenced mainly by harvest date. In a cultivar/rectangularity experiment no effect of rectangularity was detected, and the cultivar mainly affected the α parameter, the β parameter being not significantly different between cultivars. Density was shown to have a major effect on the yield/tenderometer relationship. Yields in excess of 9.9 tonnes/ha (8 800 lb/acre) at a tenderometer reading of 120 (T120) were obtained.  相似文献   
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