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11.
J W Tyler B J Steevens D E Hostetler J M Holle J L Denbigh 《American journal of veterinary research》1999,60(9):1136-1139
OBJECTIVE: To compare the concentration of IgG in colostrum between Holstein and Guernsey cows and among cows of various lactations. DESIGN: Cross-sectional cohort study. SAMPLE POPULATION: Colostrum samples from 77 Holstein and 24 Guernsey cows. PROCEDURE: Colostrum samples were obtained from 101 cows. Colostral IgG concentration was determined, using a radial immunodiffusion assay. Regression analysis was used to determine the effect of breed and lactation number on colostral IgG concentration. Survival analysis and t-tests were used to compare the proportion of colostrum samples that would provide 100 g of IgG for various volumes of colostral intake. RESULTS: Guernsey cows produced 36.4 g of IgG/L of colostrum more than that of Holstein cows. Cows in the third or greater lactation produced 19.5 g of IgG/L of colostrum more than that of first-lactation cows. The IgG concentration of colostrum produced by second-lactation cows did not differ significantly from that produced by first-lactation cows. The colostral IgG concentration of these Holstein and Guernsey cows was higher than values that have been reported elsewhere. CONCLUSIONS AND CLINICAL RELEVANCE: Volume of colostrum needed to meet IgG intake goals is probably lower for Guernsey cows than Holstein cows. Colostrum from first-lactation cows was adequate in IgG content. The practice of discarding colostrum from first-lactation cows on the basis of inadequate IgG content was not justified in this study. 相似文献
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Dawes ME Tyler JW Hostetler D Lakritz J Tessman R 《Journal of the American Veterinary Medical Association》2002,220(6):791-793
OBJECTIVE: To evaluate diagnostic utility of a commercially available immunoassay for assessing adequacy of passive transfer of immunity in neonatal calves. DESIGN: Prospective study. ANIMALS: 123 calves. PROCEDURE: Blood and serum samples were obtained from the calves prior to 2 weeks of age. The immunoassay was performed, along with refractometry and an 18% sodium sulfite turbidity test. Serum IgG concentration was determined with a radial immunodiffusion assay. Sensitivity and specificity of the immunoassay, refractometry, and the sodium sulfite test were calculated by comparing results with results of the radial immunodiffusion assay. RESULTS: Sensitivity and specificity of the blood IgG immunoassay were 0.93 and 0.88, respectively, compared with 1.00 and 0.53 for the sodium sulfite test. For refractometry, sensitivity and specificity were 0.71 and 0.83, respectively, when a serum total solids concentration of 5.2 g/dl was used as the cutoff between positive and negative test results. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that the immunoassay performs well in detecting calves with inadequate passive transfer of immunity. 相似文献
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Stockham SL Kjemtrup AM Conrad PA Schmidt DA Scott MA Robinson TW Tyler JW Johnson GC Carson CA Cuddihee P 《Veterinary pathology》2000,37(1):11-21
A 6-year-old Simmental cow infected with Theileria buffeli had a clinical disease characterized by theilerial parasitemia, macrocytic normochromic anemia with acanthocytosis and spherocytosis, lymphoid hyperplasia (lymphocytosis, edematous lymphadenomegaly), dysproteinemia, evidence of liver disease, and a low serum antibody titer against T. buffeli. The cow was in a herd in which all cattle originated in Missouri; 22/75 (29%) of cattle had a theilerial parasitemia and 26/75 (35%) had titers to T. buffeli of > or =1:160. Classification of the Missouri bovine organism as T. buffeli was based on DNA sequencing and comparison to sequences for T. buffeli and Theileria sp. type A obtained from GenBank. Intraerythrocytic veils and piroplasms were seen during transmission electron microscopy. The organism was successfully transmitted to two splenectomized calves, which developed mild anemias while parasitemic. Blood from the second calf was used as the source of T. buffeli antigen for an indirect immunofluorescence antibody test. Theilerial isolates from a Missouri white-tailed deer were also sequenced and resembled Theileria sp. types F and G and were not consistent with the bovine organism. 相似文献
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Carolyn J. Henry William G. Brewer Jr. Jeff W. Tyler William R. Brawner Ralph A. Henderson Gerald H. Hankes Natalie Royer 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1998,12(6):436-439
Case records of 64 dogs with nasal adenocarcinoma were reviewed. The effects of age, gender, tumor stage, presence of metastatic lesions, and treatment method on survival time were examined. Surgery groups included rhinotomy (n = 9), transnasal curettage (n = 29), and no surgery (n = 26). Chemotherapy groups included fluorouracil-cyclophosphamide combination therapy (n = 15), mitoxantrone (n = 7), and no chemotherapy (n = 42). Fifty-three dogs received fractionated cobalt 60 radiation therapy. Surgical procedure, chemotherapy group, and stage of primary tumor were not significantly associated with survival time ( P > .05). Dogs that received radiation therapy had a significantly longer median survival time (424 days) than dogs that did not (126 days) ( P = .0001). The presence of either regional lymph node or pulmonary metastasis was associated with significantly shorter median survival time (109 days) when compared to dogs without metastases (393 days) ( P = .0125). When only dogs that had received radiation therapy were considered, neither surgical treatment nor chemotherapy group was associated with significant changes in median survival time. An alternate staging system emphasizing the presence or absence of metastases is proposed. Key words: Chemotherapy; Metastasis; Radiotherapy. 相似文献
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FACIAL FIBROSARCOMA IN TWO COWS 总被引:1,自引:0,他引:1
Lisa G. Britt DVM MS Ohn R. Middleton DVM Reginlad A. Valdez DVM MS Russell L. Tucker DVM Steven M. Parish DVM Jeff W. Tyler DVM PhD 《Veterinary radiology & ultrasound》1998,39(1):18-21
Fibrosarcoma is a common tumor affecting bone, but is uncommon in cows, Reported here are two bovine cases of facial fibrosarcoma that were very invasive. 相似文献