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171.
A novel hereditary disorder of platelets was identified across 5 generations of a family of Greater Swiss Mountain dogs. The first dog identified with the mutation bled excessively following routine ovariohysterectomy and required multiple transfusions. Coagulation screening assays, platelet counts, and von Willebrand factor antigen activity were within reference intervals. Flow cytometric studies indicated that platelets from the affected dog expressed normal levels of glycoproteins IIb and IIIa and responded to 2 platelet-activating agents, convulxin and platelet-activating factor, but not to ADP. Based on DNA studies, a 3 base-pair deletion predicted to result in elimination of a serine from the extracellular domain was identified in the gene encoding P2Y12, an ADP receptor protein located on platelet membranes. Flow cytometric analysis of platelets and studies of DNA performed concurrently on 2 unrelated Greater Swiss Mountain dogs were unremarkable. The mutation was subsequently identified in the sire, the maternal grand-dam, a maternal great grandparent, a paternal great grandparent, and a great-great grandparent. The sire was homozygous, but had not yet been identified as having a hemostatic disorder; the other 4 dogs were carriers. This is the first report of a mutation in the gene encoding the ADP receptor P2Y12 in a domestic animal. P2Y12 is the same receptor targeted by ticlopidine and clopidogrel, platelet inhibitors used in lieu of aspirin in people at risk for cardiovascular disease; thus, spontaneous bleeding is not expected unless there are other contributing factors. This disorder is particularly troublesome because spontaneous hemorrhage is absent to mild in affected dogs; however, following routine surgical procedures or trauma, excessive bleeding could occur and have possible fatal consequences.  相似文献   
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Background: Little is known about the efficacy of commonly used acid suppressants on intragastric pH in dogs. Objective: To compare the effect of oral famotidine, 2 formulations of omeprazole, and placebo on intragastric pH in dogs with a catheter‐free, continuous pH monitoring system. Animals: Six healthy adult mixed‐breed colony dogs. Methods: Utilizing a randomized, 4‐way cross over, open‐label study, dogs were administered famotidine PO (1.0–1.3 mg/kg q12h), omeprazole tablet (1.5–2.6 mg/kg q24h), omeprazole reformulated paste (RP) (Gastrogard, 1.5–2.6 mg/kg q24h), and placebo for 7 days followed by a 10‐day washout period. Radiotelemetric pH capsules were placed with gastroscopy assistance to continuously record intragastric pH for 4 days (days 4–7 of dosing). The percentage of time that intragastric pH was ≥3 and ≥4 was compared among treatment groups using repeated measures of analysis of variance. Tukey's Studentized range test was used to determine which groups were different with α= 0.05. Results: Mean ± SD percent time intragastric pH was ≥3 and ≥4 was 22 ± 8% and 14 ± 6% for famotidine, 63 ± 14% and 52 ± 17% for omeprazole tablet, 54 ± 17% and 44 ± 18% for omeprazole RP, and 6 ± 6% and 5 ± 5% for placebo. Both omeprazole formulations significantly increased intragastric pH compared with famotidine and placebo, but omeprazole tablet and RP was not significantly different from each other. Conclusion: Oral omeprazole tablet and RP provide superior gastric acid suppression to famotidine, and should therefore be considered more effective for the treatment of acid related disorders in dogs.  相似文献   
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In order to study the metabolic profile of ostriches in relation to diet, 40 animals of both sexes were divided equally into two groups and fed two diets ad libitum consisting, on a dry matter basis, of the same commercial concentrate (60%) for the two groups and of corn silage (group A) or alfalfa hay (group B). In the morning, after about 12 h of fasting, blood was collected from the wing vein. The following haematological parameters were determined with an automatic system (Ektachem 250 analyser, Kodak): glucose, cholesterol, triglycerides, lactate (LAC), total protein (TP), uric acid, total bilirubin (Tbil), creatinine (CREA), calcium (Ca), magnesium (Mg), phosphorus (P), sodium (Na), potassium (K), chloride (Cl), iron (Fe), aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (AP), cholinesterase (ChE), α-amylase (Amyl), lipase (LIP) and γ-glutamyltrasferase (GGT). Diet significantly affected some parameters of the metabolic profile. Indeed, owing to the presence of alfalfa hay in the diet, group B showed, in comparison to group A, significantly higher values of uric acid (222.5 vs 387.5 mmol/L, p < 0.01), GGT (8.50 vs 11.3 U/L, p < 0.05), Tbil (8.50 vs 10.7 mmol/L, p < 0.05), Ca (2.41 vs 2.83 μmol/L, p < 0.01), Mg (1.01 vs 1.18 μmol/L, p < 0.05) and K (2.71 vs 3.16 μmol/L, p < 0.01). The levels of creatinine (27.3 vs 32.6 mmol/L, p < 0.05) and AST (344.9 vs 461.4 U/l, p < 0.01) were also higher for group B.  相似文献   
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苦马豆素主要存在于豆科棘豆属和黄芪属植物如疯草中,动物采食大量疯草会发生神经中枢紊乱,苦马豆素中毒的母畜表现不孕、流产,产死胎、畸胎等,引起繁殖能力下降,妨碍家畜繁育和品种优化,给我国草原畜牧业造成严重的经济损失,严重制约了我国西部草原牧区养殖业的持续发展。现通过对疯草主要毒性成分苦马豆素对母畜的繁殖性能指标、生殖器官组织形态学病理变化和生殖激素的影响进行综述,旨在为母畜疯草中毒引起的繁殖机能紊乱疾病提供治疗及预防思路,降低牧区养殖业经济损失,提高我国畜牧业长远发展的能力。  相似文献   
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PEG预处理提高玉米种子活力和萌发代谢的效应   总被引:3,自引:1,他引:3  
本文研究了PEG预处理对玉米种子活力及萌发代谢性酶活力的影响。结果表明,PEG处理可以提高玉米种子活力及幼苗抗高温的能力,增强萌发玉米种子的呼吸作用,明显提高萌发期间淀粉酶、脂肪酶、转氨酶的活力。  相似文献   
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