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41.
FA Bruna EG De Di Nasso M Soaje RP Deis RW Carón 《Reproduction in domestic animals》2010,45(5):796-802
The role of opioid peptides in the secretion of oxytocin (OT) and prolactin (PRL) induced by sucking was studied in goats. Seven goats were isolated with their kids (four singletons and three twins) in individual corrals 3–4 weeks after parturition. On day 1 of the experiment, the kids were separated from the does for 7 h and were weighed before and 15 min after being reunited with their mothers to assess the amount of milk obtained by sucking. The does were blood‐sampled 10 min before and at the end of the sucking period. On day 2, a similar protocol was followed, but naloxone was given immediately after the first blood sample. On day 3, the protocol was repeated but saline vehicle was injected instead of naloxone. On day 5, the naloxone experiment was repeated as on day 2. Milk ejection was evaluated as the difference in the weight of the kids before and after sucking for 15 min, and the maternal serum levels of OT and PRL were measured by radioimmunoassay. A significant decrease in the weight gain of the kids was obtained when the mothers were treated with naloxone on day 2. Consistently, serum levels of OT and PRL induced by sucking were significantly reduced; indicating that sucking‐induced OT secretion for milk ejection in lactating goats is facilitated by opioid peptides. In a second experiment performed in the same animals 10 days later, the administration of OT, immediately after naloxone administration, prevented the decrease in the weight gain induced by naloxone, suggesting that the effect of the opioid antagonist on milk ejection in goats is a result of a reduced OT secretion. The results of this study confirm the importance of sucking‐induced OT secretion for milk ejection in lactating goats, and indicate that OT and PRL secretion are regulated by opioid peptides in this species. 相似文献
42.
利用26对黄牛微卫星引物,对分别来自云南省泸水县凤凰山大额牛保种区和贡山县独龙野牛种源保护基地的2个大额牛群体进行遗传变异分析,研究其群体内的遗传变异和群体间的遗传分化。结果共检测到105个等位基因,每个座位的等位基因数从2~6不等,所有座位平均等位基因数、平均有效等位基因数、平均期望杂合度、平均多态信息含量分别为4.0385±0.9999,3.1393±0.9507,0.6490±0.1246和0.5904±0.1334,表明大额牛群遗传多样性比较丰富。F统计量、基因流、Nei氏遗传距离和遗传相似系数等值反映出两个群体遗传差异较小,遗传分化不明显,遗传一致性较大。 相似文献
43.
曾宪玮 ZENG XIAN WEI 彭德忠 PENG DE ZHONG 邹文生 ZOU WEN SHENG 彭洁贤 PENG JIE XIAN 陈祥发 CHEN XIANG FA 陈琨 CHEN KUN 《江西林业科技》2001,(6):23-25
通过对宜丰县云峰尖林场毛竹示范林的经营状况进行调查,分析了其经济效益、社会效益、生态效益。 相似文献
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45.
R E Isaacson L D Firkins R M Weigel F A Zuckermann J A DiPietro 《American journal of veterinary research》1999,60(9):1155-1158
OBJECTIVE: To determine whether stress associated with transportation or feed withdrawal increased fecal shedding of Salmonella Typhimurium among pigs experimentally infected with the organism. ANIMALS: 86 healthy pigs. PROCEDURE: Pigs were challenge exposed with Salmonella Typhimurium at 4 weeks old and reared conventionally. When pigs reached market weight, they were assigned to groups and subjected to various combinations of transportation and feed withdrawal. Ileocecal contents were collected after slaughter and tested for Salmonella Typhimurium. RESULTS: Salmonella Typhimurium was not detected in feces collected from pigs just prior to slaughter. When feed was withheld for 24 hours prior to slaughter, the proportion of transported pigs with Salmonella Typhimurium in ileocecal contents at the time of slaughter was not significantly different from the proportion of nontransported pigs. However, when feed was not withheld prior to slaughter, the proportion of transported pigs with Salmonella Typhimurium in ileocecal contents at the time of slaughter was significantly higher than the proportion of nontransported pigs. CONCLUSIONS AND CLINICAL RELEVANCE: When carrier pigs remained on feed, transportation stress increased the proportion positive for Salmonella sp. On the basis of results reported here, it is suggested that producers withhold feed from pigs for 24 hours prior to transportation to a slaughter plant. 相似文献
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47.
The existence of a dominant massive planet, Jupiter, in our solar system, although perhaps essential for long-term dynamical stability and the development of life, may not be typical of planetary systems that form around other stars. In a system containing two Jupiter-like planets, the possibility exists that a dynamical instability will develop. Computer simulations suggest that in many cases this instability leads to the ejection of one planet while the other is left in a smaller, eccentric orbit. In extreme cases, the eccentric orbit has a small enough periastron distance that it may circularize at an orbital period as short as a few days through tidal dissipation. This may explain the recently detected Jupiter-mass planets in very tight circular orbits and wider eccentric orbits around nearby stars. 相似文献
48.
Objective To evaluate organoleptic postmortem inspection techniques for bovine livers and kidneys.
Study design At Australian export abattoirs, bovine liver and kidneys are assessed and graded by qualified meat inspectors during normal operations. Over a 12-month period at a large abattoir in eastern Australia during 1997 and 1998, a sample of these organs was reassessed independently using a range of pathological and microbiological methods. Agreement between routine inspection and independent assessment was evaluated using methods of inter-rater agreement.
Results A total of 944 livers and 1374 kidneys were included in the study. All of these organs had been classified during routine inspection. The authors examined 363 livers and 329 kidneys both grossly and histologically, including 36 livers and 14 kidneys that were also subjected to microbiological examination. All other organs were only examined grossly. There was only a moderate level of agreement between the routine and independent assessment methods. For livers, the percentage agreement was 80.2%, McNemar's test of symmetry 55.2 (3 degrees of freedom, P < 0.001) and kappa 0.63. For kidneys, the percentage agreement was 67.8%, McNemar's test of symmetry 9.9 (1df, P = 0.002) and kappa 0.35.
Conclusions The results reinforce concerns from a number of authors about organoleptic postmortem inspection. Risk assessment methodologies offer the opportunity to modify inspection techniques in a manner that is most relevant to current public health concerns. 相似文献
Study design At Australian export abattoirs, bovine liver and kidneys are assessed and graded by qualified meat inspectors during normal operations. Over a 12-month period at a large abattoir in eastern Australia during 1997 and 1998, a sample of these organs was reassessed independently using a range of pathological and microbiological methods. Agreement between routine inspection and independent assessment was evaluated using methods of inter-rater agreement.
Results A total of 944 livers and 1374 kidneys were included in the study. All of these organs had been classified during routine inspection. The authors examined 363 livers and 329 kidneys both grossly and histologically, including 36 livers and 14 kidneys that were also subjected to microbiological examination. All other organs were only examined grossly. There was only a moderate level of agreement between the routine and independent assessment methods. For livers, the percentage agreement was 80.2%, McNemar's test of symmetry 55.2 (3 degrees of freedom, P < 0.001) and kappa 0.63. For kidneys, the percentage agreement was 67.8%, McNemar's test of symmetry 9.9 (1df, P = 0.002) and kappa 0.35.
Conclusions The results reinforce concerns from a number of authors about organoleptic postmortem inspection. Risk assessment methodologies offer the opportunity to modify inspection techniques in a manner that is most relevant to current public health concerns. 相似文献
49.
LINDA VAN HOOGMOED DVM Diplomate ACVS JACK R. SNYDER DVM PHD Diplomate ACVS GREGORY ROBERTS DVM MS Diplomate ACVR FA YE A. HARMON 《Veterinary surgery : VS》1997,26(6):497-501
Objective —The purpose of this study was to decribe the clinical presentation, diagnostic evaluation, and surgical management of a llama with an ectopic ureter.
Animals or Sample Population —Nine-month-old female llama.
Results —The diagnostic evaluation included the use of computed tomography and an excretory ureterogram to confirm and identify the location of the ectopic ureter. Surgical management involved a unilateral nephrectomy.
Conclusions and Clinical Relevance —Computed tomography is a valuable asset to diagnose the presence and terminal location of an ectopic ureter in llamas, and nephrectomy appears to be a viable procedure to resolve the subsequent urinary incontinence. 相似文献
Animals or Sample Population —Nine-month-old female llama.
Results —The diagnostic evaluation included the use of computed tomography and an excretory ureterogram to confirm and identify the location of the ectopic ureter. Surgical management involved a unilateral nephrectomy.
Conclusions and Clinical Relevance —Computed tomography is a valuable asset to diagnose the presence and terminal location of an ectopic ureter in llamas, and nephrectomy appears to be a viable procedure to resolve the subsequent urinary incontinence. 相似文献
50.