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1.
抑制素与家畜繁殖   总被引：3，自引：0，他引：3  
抑制素与家畜繁殖田允波（云南农业大学动物科技学院昆明６５０２０１）抑制素（ｉｎｈｉｂｉｎ）是一种主要由性腺分泌的糖蛋白激素。早在１９３２年ＭｃＣｕｌａｇｈ就发现一种水溶性的睾丸提取物，能特异性地抑制垂体分泌ＦＳＨ，并将它命名为“抑制素”。Ｊｏｎｇ等（...  相似文献   

2.
生长抑素（ＳＳ）是一种抑制动物生长的多肽类激素,主要由下丘脑分泌。它通过抑制体内多种促进生长的激素如：生长激素（ＧＨ）、胰岛素、胰高血糖素（ＧＧ）、促甲状腺激素（ＴＳＨ）等的分泌而抑制生长。一般认为ＧＨＩＧＦ１是动物生长的调控中心。ＧＨ的分泌同时受ＳＳ和生长激素释放激素（ＧＲＦ）所控制,前者抑制ＧＨ分泌,后者促进ＧＨ分泌。ＧＨ通过与受体结合,诱导肝细胞产生ＩＧＦ１,而ＩＧＦ１能直接作用于动物体内的多种组织,促进蛋白质的合成,促进细胞增殖,从而促进肌肉、内脏和骨骼的生长〔１〕。利用免疫中和…  相似文献   

3.
抑制素免疫对牛繁殖的影响   总被引：3，自引：1，他引：3  
抑制素是一种主要由动物性腺9睾丸的支持细胞和卵巢的颗粒细胞）分泌的一种异二聚体糖蛋白激素，由两个二硫键连接两个不同的亚单位（α和β）构成。抑制素对垂体FSH分泌和／或合成具有选择性地抑制作用。抑制素免疫中和技术能特异性地刺激FSH分泌，进而促进配子生成，提高动物繁殖力。  相似文献   

4.
抑制素主动免疫对山羊繁殖率的影响   总被引：9，自引：0，他引：9  
抑制素主要是由雌性动物的卵泡颗粒细胞和雄性动物睾丸的支持细胞分泌的一种糖蛋白激素,其主要生理作用是特异性地抑制垂体ＦＳＨ的分泌。近年来,国外学者已在猪、牛、绵羊等家畜上证实了抑制素免疫对家畜生殖功能的重要调节作用以及提高动物繁殖力的可能性。但尚未见到抑制素免疫对山羊生殖活动影响的研究报道。本研究旨在应用纯化的猪抑制素对山羊进行主动免疫,探讨免疫对排卵率和血浆ＦＳＨ水平的影响及作用。１　材料与方法１－１　试验动物及分组选购８只母山羊,年龄２～４岁,平均体重为３５－６ｋｇ。每天由专人观察其发情表现,…  相似文献   

5.
猪卵泡抑制素主动免疫对山羊生殖的影响   总被引：4，自引：0，他引：4  
抑制素是由动物的性腺分泌的一种糖蛋白,主要生理作用是反馈性抑制ＦＳＨ的合成和分泌。用抑制素对动物进行主动免疫,产生抑制素抗体中和内源性抑制素,从而削弱或解除它对ＦＳＨ分泌的抑制作用,引起动物排卵数增加,可能达到多产的目的。这种方法不仅与在生产和实验中广泛应用的促性腺激素处理一样可以提高动物的排卵率,而且可以弥补促性腺激素处理个体反应不一的缺陷,同时还能提高处理后几个胎次的产仔数,这在畜牧生产中有重要的应用价值。为此,本实验制备猪卵泡抑制素,并用它免疫山羊,探讨它用于提高家畜繁殖力的方法和可能性。1　材料…  相似文献   

6.
禽类卵泡抑制素研究现状   总被引：7，自引：0，他引：7  
抑制素（Ｉｎｈｉｂｉｎ，以下简称ＩＢ）是一种由性腺分泌的糖蛋白激素，它主要调控垂体ＦＳＨ（促卵泡素）的分泌。自１９３２年Ｍａｃｕｌａｇｈ提出这个概念以来，动物抑制素的研究日益受到人们的重视。目前对哺乳动物抑制素合成部位、分子结构及生理作用已经有了深入...  相似文献   

7.
抑制素免疫与超数排卵   总被引：2，自引：0，他引：2  
寻找一种简单的繁殖技术以提高排卵率或用作超数排卵是长期以来的目标。虽然利用促性腺激素的超排技术已成为获得可移植胚胎的有效手段,但仍有许多问题尚未解决。最突出的问题是:外源促性腺激素处理后个体差异较大,甚至出现ＰＭＳＧ处理后大卵泡不排卵的报道[1]。近年来国内外学者发现抑制素对垂体ＦＳＨ具有负反馈调节作用,认为内源性抑制素的抑制可能缓解这些问题,因而在促进动物多产和超排的研究中开始关注抑制素及其免疫中和技术[2,3,4]。1　抑制素特性抑制素(Ｉｎｈｉｂｉｎ,ＩＮＨ)是一种由动物性腺分泌的糖蛋白激素,是由α、β两个亚…  相似文献   

8.
抑制素主动免疫对山羊繁殖率的影响   总被引：4，自引：0，他引：4  
选用８只母山羊随机分成两组,试验组用卵巢抑制素与血清蛋白偶合物进行主动免疫,探讨免疫对排卵率和血浆ＦＳＨ水平的影响。结果显示,试验组山羊的抗体效价分别为１：１２８、１：６４、１：３２和１：３２,且卵巢黄体数显著高于对照组（Ｐ〈０．０５）,ＦＳＨ平均水平极显著高于对照组（Ｐ〈０．０１）。这表明,抑制素主动免疫能够引起血浆ＦＳＨ水平的升高,提高排卵率,可以改善母山羊的繁殖性能。  相似文献   

9.
抑制素研究进展   总被引：2，自引：0，他引：2  
抑制素是一种主要由性腺分泌的糖蛋白激素,对ＦＳＨ起负反馈调节物作用。由于其具免疫原性,外源抑制素通过免疫调节可降低体内抑制素的生物活性,导致ＦＳＨ浓度升高,使排卵率和产仔数增加,近年来其作为多胎疫苗的角色已越来越为人们所重视。本文介绍了抑制素的生物学特性,还回顾了抑制素的几种主要测定方法,着重综述了抑制素对雌、雄动物生殖机能的调节作用。  相似文献   

10.
综述了太湖猪高繁殖力内分泌学机制的研究进展。结果表明太湖猪促黄体素（ＬＨ）、促卵泡素（ＦＳＨ）的高含量以及ＦＳＨ分泌对抑制素的抑制效应较不敏感,尤其是ＦＳＨ的高含量,很可能是太湖猪高排卵率的重要因素之一。  相似文献   

11.
1-(2-Chloroethyl)3-cyclohexyl-1-nitrosourea (CCNU) is an alkylating agent in the nitrosourea subclass. A prospective evaluation of CCNU was done to determine the maximally tolerated dosage of CCNU in tumor-bearing cats. Response data were obtained when available. Twenty-five cats were treated with CCNU at a dosage of 50-60 mg/m3 body surface area. Complete hematologic data were available for 13 cats. Neutropenia was the acute dose-limiting toxicity. The median neutrophil count at the nadir was 1,000 cells/microL (mean, 2,433 cells/microL; range, 0-9,694 cells/microL). The time of neutrophil nadir was variable, occurring 7-28 days after treatment, and counts sometimes did not return to normal for up to 14 days after the nadir. Based on these findings, a 6-week dosing interval and weekly hematologic monitoring after the 1st treatment with CCNU are recommended. The nadir of the platelet count may occur 14-21 days after treatment. The median platelet count at the nadir was 43,500 cells/microL. No gastrointestinal, renal, or hepatic toxicities were observed after a single CCNU treatment, and additional studies to evaluate the potential for cumulative toxicity should be performed. Five cats with lymphoma and 1 cat with mast cell tumor had measurable responses to CCNU. Phase II studies to evaluate antitumor activity should be completed with a dosing regimen of 50-60 mg/m3 every 6 weeks.  相似文献   

12.
Human and equine athletes are reported to have a high prevalence of gastric disease, and anecdotal evidence suggests a similar phenomenon applies to racing sled dogs. To investigate the prevalence of gastric disease in racing sled dogs, we conducted 2 gastroscopy studies on dogs competing in the annual Iditarod Sled Dog Race. A pilot study of dogs that were either dropped from the 2000 Iditarod Sled Dog Race because of illness or that finished the race indicated that, approximately 5 days after competing, 10 of 28 dogs (35%) had endoscopic evidence of gastric ulceration, erosion, or hemorrhage. The next year, an endoscopic study of 73 dogs participating in the 2001 Iditarod race was performed in order to evaluate a larger population of dogs. Data from 70 of these dogs could be used; 34 (48.5%) had ulceration, erosion, gastric hemorrhage, or some combination of these findings. When this group of 70 dogs was compared retrospectively to a control group of 87 dogs presented to the Texas A&M University (TAMU) Veterinary Medical Teaching Hospital, the Iditarod sled dogs had a significantly higher prevalence (P = .049) of gastric lesions. These findings suggest that, similar to athletes of other species, elite canine athletes have an increased prevalence of gastric disease compared to the canine population at large.  相似文献   

13.
Continuous rate infusion (CRI) of furosemide in humans is considered superior to intermittent administration (IA). This study examined whether furosemide CRI, compared with IA, would increase diuretic efficacy with decreased fluid and electrolyte fluctuations and activation of the renin-angiotensin-aldosterone system (RAAS) in the horse. Five mares were used in a crossover-design study. During a 24-hour period, each horse received a total of 3 mg/kg furosemide by either CRI (0.12 mg/kg/h preceded by a loading dose of 0.12 mg/kg IV) or IA (1 mg/kg IV q8h). There was not a statistically significant difference in urine volume over 24 hours between methods; however, urine volume was significantly greater after CRI compared with IA during the first 8 hours ([median 25th percentile, 75th percentile]: 9.6 L [8.9, 14.4] for CRI versus 5.9 L [5.3, 6.0] for IA). CRI produced a more uniform urine flow, decreased fluctuations in plasma volume, and suppressed renal concentrating ability throughout the infusion period. Potassium, Ca, and Cl excretion was greater during CRI than IA (1,133 mmol [1.110, 1,229] versus 764 mmol [709, 904], 102.7 mmol [96.0, 117.2] versus 73.3 mmol [65.0, 73.5], and 1,776 mmol [1,657, 2.378] versus 1,596 mmol [1,457, 1,767], respectively). Elimination half-lives of furosemide were 1.35 and 0.47 hours for CRI and IA, respectively. The area under the excretion rate curve was 1,285.7 and 184.2 mL x mg/mL for CRI and IA, respectively. Furosemide CRI (0.12 mg/kg/h) for 8 hours, preceded by a loading dose (0.12 mg/kg), is recommended when profound diuresis is needed acutely in horses.  相似文献   

14.
Tropical Animal Health and Production -  相似文献   

15.
The epidemiology of H. placei and of other gastrointestinal nematodes in yearling dairy cattle was examined on two farms in Kiambu District, central Kenya during each of 13 one-month periods from April 1993 to April 1994. On each farm, 32 newly weaned dairy calves were given a single dose of albendazole and then placed on experimental pastures. Twelve of the animals were designated for bi-monthly slaughter (n = 2) and analysis of worm population characteristics and 20 were designated for blood and faecal collection and for weighing. Two parasite-free tracer calves were grazed alongside the weaner calves each month throughout the study period and were also slaughtered for analysis of worm populations. Faecal egg counts, haematological and serum pepsinogen determinations, herbage larval counts, and animal live weight changes were recorded monthly. The study revealed that Haemonchus placei, Trichostrongylus axei, Cooperia spp. and Oesophagostomum radiatum were responsible for parasitic gastroenteritis and that H. placei was the predominant nematode present in the young cattle on both farms. Faecal egg counts from resident cattle and necropsy worm counts revealed that pasture larval levels were directly related to the amount of rainfall. The total worm burdens in the animals were highest during the rainy season (March–June and October–December) and lowest during the dry seasons (July–September and January–February). The very low recovery of immature larvae of H. placei from the tracer calves indicated that arrested development is not a feature of the life cycle of this parasite in central Kenya. The maintenance of the parasite population depended on continuous cycling of infection between the host and the pasture. The agroclimatic conditions of the study area were such that, in general, favourable weather conditions for the development and survival of the free-living stages of gastrointestinal nematodes existed all year round.  相似文献   

16.
The occurrence of ectoparasites in sheep flocks is frequently reported but seldom quantified. Sheep production used to be a predominantly family activity in the state of Sa~o Paulo (Brazil), but it began to become a commercial activity in the past decade. Thus, information about the ectoparasites existing in sheep flocks has become necessary. The present data were obtained by means of questionnaires sent to all sheep breeders belonging to the `Associaça~o Paulista de Criadores de Ovinos' (ASPACO; Sa~o Paulo State Association of Sheep Breeders). Response reliability was tested by means of random visits paid to 10.6% of the respondents. Most of the properties (89.5%) reported the presence of one or more ectoparasites. Screw-worm (Cochliomyia hominivorax) was the most frequent ectoparasite (72.5%), followed by bot fly larvae (Dermatobia hominis, 45.0%), ticks (Amblyomma cajennense) and Boophilus microplus, 31.3%) and finally lice (Damalinia ovis, 13.8%). Combined infestations also occurred, the most common one being screw-worm with bot fly larvae (36.0%) followed by bot fly larvae with ticks (13.9%), screw-worm with ticks (9.3%), bot fly larvae with lice (6.9%), and ticks with lice (5.0%). The most common triple combination was screw-worm, bot fly larvae and ticks (12.8%). Breeds raised for meat or wool were attacked by bot fly larvae and ticks more often than other breeds. Lice were only absent from animals of indigenous breeds. The relationships among these ectoparasites are discussed in terms of sheep breeds, flock size, seasonality and the ectoparasitic combinations on the host.  相似文献   

17.
Our particular attention in this article was given to natural mediators for macrophages isolated from the sites of tissue injury. A number of chemotactic factors, which may satisfy many criteria making them acceptable as inflammatory leucocyte chemotactic factors, has been separated. Among them, our laboratory has isolated three macrophage (monocyte) chemotactic factors (MCF-a, -b and -c). Their purification, characterization and functional specificity are discussed.  相似文献   

18.
Comparison of different tests to diagnose feline infectious peritonitis   总被引：1，自引：0，他引：1  
  相似文献   

19.
An experiment was conducted to study disappearance of C14 to C18 fatty acids, lag times and biohydrogenation (BH) rates of C18 fatty acids of ground soya bean and canola seeds in situ. Three ruminally fistulated Dallagh sheep were used to determine ruminal BH of unsaturated fatty acids (UFAs). Differences in the disappearance of fatty acids through the bags and lag times were observed between the oilseeds. We saw that the longer the incubation time of the oilseeds in the rumen, the lower the content of C18:2 and C18:3. Significantly higher lag times for both C18:2 and C18:3 were observed in ground canola compared to ground soya bean. BH rates of C18:2 and C18:3 fatty acids in soya bean were three times higher than those of canola. These results suggest that the fatty acid profile of fat source can affect the BH of UFAs by rumen micro‐organisms. So that UFAs of canola had higher ability to escape from ruminal BH. It seems that fatty acid profile of ruminant products is more affected by canola seed compared to soya bean seed.  相似文献   

20.
Serum biochemical values and the wet weight to dry weight ratios of tissues were determined in yaks in Shandan county of Gansu province. The liver, kidney, heart and muscle contents of seven elements in yaks were also analysed. Most serum biochemical values were similar to those of cattle, camels and sheep, but the calcium concentration was considerably above the normal range for other ruminants. The liver contained the highest concentrations of copper, manganese and cobalt and the kidney of selenium, iron and calcium.Abbreviations Alb albumin - ALT alanine aminotransferase - AST aspartate aminotransferase - BUN blood urea nitrogen - Chol cholesterol - Glob globulin - -GT -glutamyl transpeptidase - IP inorganic phosphorus - TP total protein  相似文献   

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