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911.
An assay was developed and proven accurate and precise for the quantification of canine serum alkaline phosphatase of bone origin (BAP). The assay uses wheat germ lectin (WGL) which selectively precipitates SAP but not liver alkaline phosphatase (LAP) in serum preincubated for 1 hour at 37 degrees C before conducting the assay. Although a large percentage of corticosteroid-induced alkaline phos- phatase (CAP) is also precipitated by WGL, the activity of this isoenzyme can be determined by utilizing the automated levamisole inhibition assay and BAP determined by subtraction except in those cases in which CAP is very markedly increased. Use of these two assay techniques in combination allows the quantification of LAP, BAP, and CAP activity in canine serum. In sera from adult dogs of various ages, BAP activity represents a mean of 21.27 -/+ 11.4 U/L; however, there was a statistical decrease in BAP activity with age. This allowed the determination of 95% confidence interval for a reference range dependent on age of the dog. Bone AP activity in puppies drops dramatically within the first 3 months, reaching a magnitude of activity consistent with that of the adult dog by approximately 15 months. BAP was increased over adult reference range in five of five dogs tested with osteosarcoma. This assay will now allow conducting a clinical study of the diagnostic significance of bone AP activity in neoplastic and metabolic diseases of bone.  相似文献   
912.
Sixty Angus (n = 29) and Angus-Sim-mental cross (n = 31) steers, averaging 9 mo of age and 277 kg of initial BW, were used in a 148-d study to determine the bioavailability of copper glycinate (CuGly) relative to feed-grade copper sulfate (CuSO(4)) when supplemented to diets high in S and Mo. Steers were blocked by weight within breed and randomly assigned to 1 of 5 treatments: 1) control (no supplemental Cu), 2) 5 mg of Cu/kg of DM from CuSO(4), 3) 10 mg of Cu/kg of DM from CuSO(4), 4) 5 mg of Cu/kg of DM from CuGly, and 5) 10 mg of Cu/kg of DM from CuGly. Steers were individually fed a corn silage-based diet (analyzed 8.2 mg of Cu/kg of DM), and supplemented with 2 mg of Mo/kg of diet DM and 0.15% S for 120 d (phase 1). Steers were then supplemented with 6 mg of Mo/kg of diet DM and 0.15% S for an additional 28 d (phase 2). Average daily gain and G:F were improved by Cu supplementation regardless of source (P = 0.01). Final ceruloplasmin, plasma Cu, and liver Cu values were greater (P < 0.05) in steers fed supplemental Cu compared with controls. Plasma Cu, liver Cu, and ceruloplasmin values were greater (P < 0.05) in steers supplemented with 10 mg of Cu/kg of DM vs. those supplemented with 5 mg of Cu/kg of DM. Based on multiple linear regression of final plasma Cu, liver Cu, and ceruloplasmin values on dietary Cu intake in phase 1 (2 mg of Mo/kg of DM), bioavailability of Cu from CuGly relative to CuSO(4) (100%) was 140 (P = 0.10), 131 (P = 0.12), and 140% (P = 0.01), respectively. Relative bio-availability of Cu from CuGly was greater than from CuSO(4) (P = 0.01; 144, 150, and 157%, based on plasma Cu, liver Cu, and ceruloplasmin, respectively) after supplementation of 6 mg of Mo/kg of DM for 28 d. Results of this study suggest that Cu from CuGly may be more available than CuSO(4) when supplemented to diets high in S and Mo.  相似文献   
913.
Molecular screening of GM1 gangliosidosis in Shiba dogs was carried out in northern Japan using blood smear specimens after prolonged storage. Of 125 specimens obtained from 3 veterinary teaching hospitals for this screening, 68 specimens (54%) were adequate for direct amplification in a polymerase chain reaction (PCR)-based DNA test, and the percentage of adequacy was different at each hospital (34%, 73%, and 100%), suggesting that the amount of blood on the smear and the storage condition of specimens may affect adequacy. Of the 68 dogs examined, 2 dogs (2.9%) were heterozygous carriers for this disease and the other dogs were all genotypically normal. The results suggest blood smear specimens can be useful for PCR testing after prolonged storage provided specimens contain a generous amount of blood and have been adequately stored. The study also suggests that GM1 gangliosidosis may be widely prevalent in the Shiba dog population in northern Japan.  相似文献   
914.
During late 2001 and early 2002, a mixed species wildlife park in North Carolina experienced an acute outbreak of morbidity and mortality in Pere David's deer (Elaphurus davidianus), axis deer (Axis axis), blackbuck antelope (Antelope cervicapra), white-tailed deer (Odocoileus virginianus), and Rocky Mountain elk (Cervus elaphus). Clinical signs varied from fulminant disease, progressing from depression to bloody scours to death in fewer than 4 days in Pere David's deer, to a more protracted form of disease, ranging from 2 wk to 3 mo, in axis deer. In moribund axis deer, high levels of anti-malignant catarrhal fever (MCF) virus antibody by competitive-inhibition enzyme-linked immunosorbent assay were detected. Ovine herpesvirus 2 (OvHV-2) DNA was detected in peripheral blood leukocytes of the affected axis deer. No other MCF viruses were detected. Retrospective examination of frozen tissue samples from the affected Pere David's deer and blackbuck antelope also confirmed the presence of OvHV-2 DNA. Initial control efforts were directed at preventing further deaths of clinically susceptible animals by removing MCF virus reservoir species, particularly ovine species. The most prevalent ovine species in the wildlife park was mouflon sheep (Ovis musimon). All sheep were removed from the park by June 2002, and the last MCF death occurred in October 2002. Since mouflon sheep had been a prominent attraction in the wildlife park, the owner wanted a means to reintroduce this species to the park. Derivation of OvHV-2-uninfected mouflon lambs was undertaken using the previously described program for production of OvHV-2-free sheep (Ovis ovis). The rederived MCF virus-negative mouflon sheep were introduced into the park in approximately January 2004. As of December 2007, no further cases of MCF have occurred since the removal of OvHV-2-positive mouflon sheep and reintroduction of the virus-free lambs. This paper describes the successful management and control of MCF in a densely populated mixed species animal park.  相似文献   
915.
OBJECTIVE: To assess the correlation between data generated by an accelerometer-based activity monitor and the distance moved in cats. STUDY DESIGN: Prospective experimental study. ANIMALS: Three, four-year-old, male, purpose-bred research cats, weighing between 5.1 and 5.9 kg. METHODS: Part I: Collar and harness mounted accelerometers were evaluated in three cats, comparing simultaneously collected accelerometer data with movement data from computer-analyzed video. Part II: Cats wore collar and harness mounted accelerometers, and data were recorded for 4 weeks to evaluate day-to-day and week-to-week variation in activity. RESULTS: Part I: 432 hours of simultaneous video and accelerometer data were collected. The correlation between accelerometer counts and distance moved was 0.82 overall. Agreement between collar and harness mounted accelerometers was excellent with only 6% of the differences in measurements lying outside the mean difference +/- 2 standard deviations. The adjusted R(2) for harness accelerometer output and 6% mobility was 0.75; for movement 0.84; and for mean velocity 0.83. Evaluation of video indicated eating, grooming and scratching created high accelerometer counts with little effect on movement. Part II: There was a significant effect of day on harness (p < 0.001) and collar (p < 0.002) counts, with counts being lowest at the weekend. There was a significant effect of week on harness-mounted accelerometer counts (p < 0.034), but not on collar-mounted accelerometer counts. Harness accelerometer counts were lowest in week 1. CONCLUSION: Output from an acceleration-based digitally integrated accelerometer correlated well with distance moved and mobility in freely moving cats provided the mobility threshold in the analysis software was > or = 6%. CLINICAL RELEVANCE: Acceleration-based activity monitors may allow for objective measurement of improved mobility following analgesic treatment for conditions such as osteoarthritis.  相似文献   
916.
Objective – To characterize the signalment, clinical findings, and prognosis of dogs with supraventricular tachycardia (SVT). Design – Retrospective study. Setting – North Carolina State University Veterinary Teaching Hospital. Animals, Intervention, and Measurements – Case selection included all patients at the veterinary teaching hospital with SVT during years 1990–2007. Medical records from dogs with at least 1 recorded episode of SVT were extracted. The signalment, history, electrocardiographic, radiographic, and echocardiographic findings, therapy, and response to therapy were reviewed and summarized. Follow‐up was conducted to determine the date and cause of death. Kaplan‐Meier survival curves were constructed and analyzed. The relationships between patient characteristics and responses to therapy and prognosis were evaluated. Main Results – Sixty‐five records documented a diagnosis of SVT. Sixty‐two percent were males. Labrador Retrievers and Boxers were overrepresented compared with the general hospital population. Median age at presentation was 9 years (range 0.5–15.5 y). The median heart rate during SVT was 270/minute (range 187–375/min). The most common presenting complaint was syncope (30%), 23% were asymptomatic at the time of diagnosis. Most dogs had structural heart disease (65%). Median survival was 472 days (<1–2007 d). Identification of sustained SVT (>30 s) did not affect survival (P=0.50), nor did the presence of congestive heart failure (P=0.70). Conclusions – The majority of dogs with SVT had structural heart disease or a severe concurrent illness at the time of SVT diagnosis. SVT, though often a persistent and occasionally sustained arrhythmia, does not appear to be a primary factor in mortality.  相似文献   
917.
A nationwide epidemiological survey of Babesia gibsoni infection in non-fighting dogs was conducted using an improved ELISA with recombinant B. gibsoni thrombospondin-related adhesive protein (BgTRAP). A total of 1206 dogs from 27 prefectures were examined and 128 (10.6%) tested positive. In the eastern part of Japan, 39 dogs out of the 559 (7.0%) examined were positive, while 89 dogs out of 647 (13.8%) tested positive in the western part of Japan. Although the percentage of dogs that tested positive was significantly (p=0.0001) lower in the eastern part compared to the western part of Japan, overall these results indicate that B. gibsoni infection of dogs has a widespread geographic distribution throughout the country. A history of tick infestation was identified as a significant risk factor for B. gibsoni infection (p=0.0091), while sex (p=0.9411), age (p=0.0920) and breed (p=0.0549) of dogs were not statistically significant risk factors. These results indicate that tick infestation is the most dominant risk factor for B. gibsoni infection of non-fighting dogs in Japan and suggest that other B. gibsoni transmission routes, such as fighting and transplacental transmission, may be less important.  相似文献   
918.
A seroepidemiological survey of Neospora caninum infection among dogs in Japan was conducted using species-specific enzyme-linked immunosorbent assay with recombinant surface antigen (Nc-SAG1t). Among 1,206 dogs examined, 126 dogs (10.4%) from 30 prefectures from Hokkaido to Okinawa were positive to N. caninum infections, which were more frequently detected in females than males. Siberian Huskies showed the highest positive rate compared with the other breeds. Dogs with pyometra and diabetes mellitus showed the higher positive rates than dogs with other diseases or without diseases.  相似文献   
919.
The aim of the present study was to investigate the effects of centrifugation pretreatment on the viability and nuclear status of porcine in vitro matured (IVM) oocytes and on the developmental competence of in vitro fertilized (IVF) oocytes (zygotes) after cryopreservation by vitrification (Solid Surface Vitrification; SSV). Mature oocytes having the first polar body after IVM and zygotes having the second polar body at 10 h after IVF were centrifuged at 10,000 x g at 37 C for 20 min and then subjected to SSV. Their viability was evaluated by morphological appearance and fluorescein diacetate staining. The nuclear status of oocytes was evaluated 6 h after vitrification. The developmental ability to the blastocyst stage of vitrified zygotes was evaluated after 6 days of in vitro culture. Although centrifugation did not damage the oocytes directly, it drastically reduced the rate of live oocytes after SSV. The rates of vitrification-induced parthenogenetic activation were similar in both centrifuged and non-centrifuged oocytes (42.4 and 47.4%, respectively). Centrifugation had no significant effects on the viability of pronuclear oocytes. The development of vitrified zygotes to the blastocyst stage was significantly lower than that of the control irrespective of centrifugation pretreatment. There was no difference in the cleavage and blastocyst rates between the control and centrifuged zygotes after vitrification. There was also no difference in the total cell numbers of blastocysts between the control and centrifuged zygotes irrespective of vitrification. These results reveal that, in IVM porcine oocytes, centrifugation pretreatment is highly detrimental to cryotolerance; however, in zygotes, it has only a slight effect on viability and does not alter the developmental competence of surviving zygotes.  相似文献   
920.
利用细胞型朊病毒蛋白(PrPc)的双荧光标记,发现PrPc NH2端和COOH端片段在N2a细胞和HpL3~4细胞内有明显不同的分布,N2a细胞是鼠成神经瘤细胞,HpL3~4细胞是prnp基因敲除鼠的海马细胞系细胞.值得注意的是,主要定位于细胞内部分的PrPc的NH2端片段,采用微管解聚剂(nocodazole)处理后在细胞内聚集.鼠PrPc的残基片段1~121、1~111和1~91在细胞内呈现适当的分布轮廓,而残基1~52和1~33不能表现出明显的分布区域,这些资料显示微管相关的PrPcNH2端片段的定位至少需要包含91个氨基残基.  相似文献   
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