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1.
下丘脑多巴胺和5-羟色胺调控鸡就巢机理的研究 总被引：19，自引：3，他引：16
利用350至450日龄的就巢粤黄鸡观察多巴胺(DA)和5-羟色胺(5-HT)受体拮抗剂氯丙嗪和赛更啶对就巢的影响.就巢第2 d开始每天口服氯丙嗪60 mg/(kg.d)或赛更啶8 mg/(kg.d),7 d后或于就巢终止后停止药物处理.试验1:13只氯丙嗪处理鸡中92.3%(12/13)于处理后5.4±1.1 d终止就巢;15只赛更啶处理鸡有60.0%(9/15)在处理后3.2±0.3 d终止就巢;全部(100%)10只同时处理氯丙嗪和赛更啶的鸡于处理后3.2±0.3 d终止就巢;8只对照组鸡在不受任何处理时持续就巢,其就巢期被主观认为22 d.试验2:7只就巢鸡在就巢的第2、4、9、14和19 d血浆PRL水平维持在200～400 ng/ml之间;9只氯丙嗪处理后终止就巢的7只鸡以及13只赛更啶处理后终止就巢的6只鸡,血浆PRL由就巢第2 d与对照组类似的高水平急剧下降到第4 d小于20 ng/ml,并至第19 d一直处于较低水平.对照组在持续就巢期间的血浆LH水平低于1.0 ng/ml,而用药后终止就巢鸡的血浆LH水平从处理前的小于1.0 ng/ml逐渐上升至第19天的3.0 ng/ml左右.药物处理后仍未终止就巢鸡的血浆PRL和LH水平都与对照组的类似.以上结果说明用DA和5-HT受体拮抗剂氯丙嗪和赛更啶处理后,抑制了垂体PRL的分泌并使鸡终止就巢,在整体水平证明了下丘脑DA和5-HT两种神经递质对就巢发生具有共同的加性促进作用. 相似文献
2.
回顾了近20年来对禽类就巢发生的内分泌和神经内分泌研究进程及状况,并推测能够使用5-羟色胺和多巴胺受体阻断类药物如赛更啶和氯丙嗪缩短家禽的就巢期,或主动免疫血管活性肠肽或催乳素抑制就巢以提高家禽的生产性能.预计在禽类就巢方面的研究进展将能帮助发现促进就巢的基因,并能利用这些基因选育出具不同就巢习性的家禽品种供应不同的家禽生产用途. 相似文献
3.
就巢行为是影响禽类繁殖力的重要因素,近年来国内外科技研究人员对禽类就巢发生的机制进行了广泛的研究,已经取得了极大的研究进展。本文以三种调控就巢行为的途径为切入点,系统介绍各种生殖激素(PRL、E_2、P、5-HT、DA、GnRH、FSH、LH、IB)在家禽就巢机制中的作用,以期为相关研究提供参考。 相似文献
4.
选择表现抱窝行为的母鹅7只,通过RIA方法测定了母鹅在抱窝期间PRL(催乳素)、P(孕酮)和17β—E2(雌二醇)水平的变化。抱窝伊始P、17β—E2含量分别为3.28±0.27ng/ml、71.74±6.45pg/ml。抱窝第11天17β—E2水平降至49.07±8.48pg/ml(P>0.05),而P水平略有升高直至第18天才出现显著下降(1.864±0.12ng/ml)。雏鹅孵出后P、17β-E2水平分别回升至2.71±0.29ng/ml(P>0.05)、142.86±19.00pg/ml(P<0.01)。休产期间P、17β—E2水平均表现一定程度的降低。血浆中PRL水平第一天为214.24±19.73uU/ml。以后呈缓慢上升趋势,抱窝第25天达到高峰395.89±29.75uU/ml(P<0.01),雏鹅孵出后PRL下降至276.32±16.10uU/ml(P<0.05),抱窝结束后PRL水平进一步降低,休产期间PRL降至最低点55.94±15.35uU/ml(P<0.01)。研究表明:PRL可以诱导以及维持母鹅表现抱窝行为,并可抑制卵巢性腺激素的生成与释放。 相似文献
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为探求LRH—A诱导双峰母驼排卵、受胎效果,应用放射免疫法测定了母驼冷冻精液输精前后外周血清孕酮含量的变化。5峰(头)输精并肌注LRH—A母驼,输精前孕酮值平均为0.15±0.02ng/ml,输精后第3天增加到0.52±0.13ng/ml,第7 天可达1.62 ±0.89ng/ml。怀孕驼第12天孕酮仍维持高水平,为1.72±0.31ng/ml;而未怀孕驼孕酮水平7天开始下降,第12天降为0.32 ±0.06ng/ml(p<0.05)。5峰母驼受胎3峰,产羔3峰。3峰仅输冷冻精液的母驼,输精前后孕酮水平显著低于肌注LRH—A母驼排卵后的孕酮水平(p<0.05),均未受胎,持续发情。 相似文献
7.
宁夏滩羊发情周期血液中促黄体素(LH)、孕酮、雌二醇——17β含量的测定 总被引：1，自引：0，他引：1
用放射免疫测定法测定了宁夏滩羊母羊(13只)外周血清中促黄体素(LH)、孕酮及雌二醇—17β的含量及其变化。血清LH的含量,在黄体期,其值很低,为5.0±0.41ng/ml,到发情开始后约6—12小时增至75.13±17.64ng/ml。孕酮含量的变化,在周期的黄体期,其值最高为2.84±0.10ng/ml;而在发情开始到发情后第二天最低0.52±0.06ng/ml。雌二醇—17β的含量是在发情开始前6—24小时时上升的;其值的变化范围是从黄体期的14.86±1.24Pg/ml到发情开始时的38.7±5.8Pg/ml。 相似文献
8.
目前,鹅繁殖性能普遍较低,大多数鹅品种年产蛋量20~40枚,严重阻碍其产业化发展。较强的就巢性是导致其繁殖性能低的重要原因。大量研究结果表明,家禽就巢行为的发生与维持是由遗传、环境和机体内分泌激素共同控制的。但是,家禽就巢主要受几种激素调控。众多研究结果表明,催乳素(prolactin,PRL)是家禽重要的生殖激素,血浆中高水平的PRL诱导和维持家禽就巢,活性血管肠肽(vosactive intestinal peptide,VIP)是PRL分泌因子,不但能促进垂体细胞分泌PRL,且还在5-羟色胺(5-HT)和多巴胺(dopamine,DA)调节PRL分泌中发挥中枢作用。因此,VIP在家禽就巢内分泌调控中起到重要的作用。 相似文献
9.
本试验将20只体况相近、未孕、不泌乳的奶山羊,随机分为利血平1组(R_1)、利血平2组(R_2)、氟哌啶醇组(H组)和对照组,每组各5只羊。R_1组和R_2组分别按每kg体重肌注利血平0.02和0.04mg,H组按每kg体重肌注氟哌啶醇0.1mg,对照组肌注生理盐水。各组于注射前的5分钟和注射后的30分钟、1、2、4、6、8和12小时采血,分离血浆,应用RIA测定血浆促乳素(PRL)水平的变化。结果对照组血浆促乳素水平波动在22.8±5.9～79.831.6ng/ml之间。R_1组和R_2组在注射后的30分钟,血浆促乳素从注射前的20.5±5.6和26.3±8.3ng/ml,分别上升到39.5±11.8和74.9±30.1ng/ml,4小时达到峰值,分别为554.4±149.2和641.6±193.8ng/ml,以后缓慢降低,于注射后的12小时降至对照组水平。H组在注射后的30分钟,血浆促乳素水平从注射前的49.0±17.2ng/ml上升到435.0±71.2ng/ml,1小时达峰值606.2±129.7ng/ml,4小时降到147.9±49.8ng/ml,于注射后12小时降到对照组水平。 相似文献
10.
本试验采用放射免疫法测定了卵巢囊肿奶牛外周血浆中促黄体素、孕酮、雌二醇和睾酮水平。测定结果,促黄体素水平卵泡囊肿为0.84±0.25ng/ml(n=12),黄体囊肿为0.83±0.23ng/ml(n=5);孕酮水平卵泡囊肿为0.56±0.30ng/ml(n=12),黄体囊肿为2.85±0.64ng/ml(n=5);雌二醇水平卵泡囊肿为28.44±22.47pg/ml(n=12),黄体囊肿为8.14±0.88pg/ml(n=5);睾酮水平卵泡囊肿为84.67±40.40pg/ml(n=12),黄体囊肿为51.98±7.77pg/ml(n=5)。认为卵巢囊肿奶牛外周血浆中促黄体素水平低于正常期奶牛的水平;卵泡囊肿奶牛血浆中孕酮水平低于1ng/ml,黄体囊肿奶牛血浆中孕酮水平高于1ng/ml;卵泡囊肿奶牛血浆中雌二醇水平较高;卵泡囊肿奶牛公牛相与体内高水平睾酮有关。 相似文献
11.
Owen J Slocombe D McMillan I 《The Canadian veterinary journal. La revue veterinaire canadienne》1986,27(9):324-328
In late December 1985, 1485 institutional veterinarians and small and mixed animal clinics across Canada were sent a questionnaire in order to assess the status of Dirofilaria immitis in Canada in 1985 and 44% of them responded. Veterinarians reported that 137,300 dogs were blood-tested to check for microfilariae and 1210 dogs were found with heartworm. Another 36 dogs were amicrofilaremic but diagnosed with heartworm disease to give the total number diagnosed in 1985 as 1247 (0.91%).
Heartworm was reported from all provinces except Prince Edward Island, Newfoundland and Saskatchewan but most (1126) of the cases were in Ontario. Southwestern Ontario continued to be the primary focus of the infection in Canada. From Quebec, 91 cases were reported mostly from and around Montreal. From Manitoba, 19 cases were reported from Winnipeg and surrounding areas. Heartworm was found most frequently in companion dogs over three years of age maintained mainly outdoors in rural areas. About 28% of the cases were observed with clinical signs of heartworm disease and 78% had a history of not having left Canada.
相似文献12.
Slocombe JO McMillan I 《The Canadian veterinary journal. La revue veterinaire canadienne》1989,30(6):504-508
In late November 1988, 1581 small and mixed animal clinics and institutional veterinarians across Canada were sent a questionnaire in order to assess the status of Dirofilaria immitis in Canada in 1988, and 46% of them responded. Veterinarians reported that 181,577 dogs were blood-tested for heartworm disease and 367 dogs were found with D. immitis microfilariae. Another 60 dogs were amicrofilaremic but diagnosed with heartworm disease to give the total number of cases diagnosed in 1988 as 441 (0.24%). 相似文献
13.
Slocombe JO McMillan I 《The Canadian veterinary journal. La revue veterinaire canadienne》1985,26(10):323-327
In late December 1984, 1853 institutional veterinarians and small and mixed animal clinics across Canada were sent a questionnaire in order to assess the status of Dirofilaria immitis in Canada in 1984 and 35% of them responded. Veterinarians reported that 97,794 dogs were blood-tested to check for microfilariae and 1417 dogs (1.45% of those tested) were found with heartworm. Another 34 dogs were amicrofilaremic, but were diagnosed as having heartworm disease, to give the total number diagnosed in 1984 as 1451 (1.48%). Heartworm was reported from all provinces except Prince Edward Island and Newfoundland but most (1310) of the cases were in Ontario. In Quebec, 126 cases were reported mostly from west of Montreal.
Heartworm was found most frequently in companion dogs over three years of age maintained mainly outdoors in rural areas. About 27% of the cases were observed with clinical signs of heartworm disease and 72% had a history of not having left Canada. Southwestern Ontario continued to be the primary focus of the infection.
相似文献14.
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Slocombe JO Villeneuve A 《The Canadian veterinary journal. La revue veterinaire canadienne》1993,34(10):630-633
In late November 1991, 1883 clinics in Canada were sent a questionnaire to assess the status of Dirofilaria immitis in dogs in 1991 and there was a 60.0% response. There were 344,031 dogs tested for heart-worm (HW), 627 were found infected and the prevalence of HW infection was 0.18%. There were 417 dogs with HW in Ontario, 116 in Manitoba, 38 in Quebec, 53 in British Columbia, three in Alberta, and one in Nova Scotia. In British Columbia, all of the infected dogs but one were from the Okanagan valley which, as from 1991, is a new focus of infection in Canada. Most dogs with HW had not been on preventive medication in 1990, and the prevalence among dogs tested and unprotected was 0.59%. That prevalence was considerably higher in endemic areas. Companion dogs, over three years of age and maintained primarily outdoors in rural areas, were most frequently infected. One cat was diagnosed with D. immitis and 33 dogs had Dipetalonema reconditium. 相似文献
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In late November 1989, 1732 clinics and institutional veterinarians were sent a questionnaire to assess the status of Dirofilaria immitis, and 51.7% responded. Of 247,716 dogs tested, 394 had D. immitis microfilariae and 51 were amicrofilaremic for a total of 445 cases and heartworm prevalence of 0.17%. Most (408) of these dogs had no preventive medication and the prevalence among dogs tested and unprotected was 1.01%. That prevalence was considerably higher in endemic areas. Thirty-seven dogs with heartworm had preventive medication. Heartworm was most frequent in companion dogs over three years of age maintained outdoors in rural areas. About 75% of the cases had never left Canada, 26% had clinical signs and 125 were not treated.
Heartworm was reported from British Columbia, Manitoba, Ontario, Quebec, Nova Scotia and Newfoundland, but 383 cases were in Ontario. South-western Ontario was the primary focus of infection. There were 33 cases in Quebec and 24 in Manitoba, mainly found in and around Metropolitan Montreal and Winnipeg respectively.
相似文献17.
Slocombe JO McMillan I 《The Canadian veterinary journal. La revue veterinaire canadienne》1988,29(8):641-646
In late November 1987, 1246 institutional veterinarians and small and mixed animal clinics across Canada were sent a questionnaire in order to assess the status of Dirofilaria immitis in Canada in 1987, and 50% of them responded. Veterinarians reported that 165,428 dogs were blood tested for heartworm disease and 511 dogs were found with D. immitis microfilariae. Another 78 dogs were amicrofilaremic but diagnosed with heartworm disease to give the total number of cases diagnosed in 1987 as 589 (0.35%). 相似文献
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Owen J Slocombe D McMillan I 《The Canadian veterinary journal. La revue veterinaire canadienne》1987,28(8):491-495
In late December 1986, 1224 institutional veterinarians and small and mixed animal clinics across Canada were sent a questionnaire in order to assess the status of Dirofilaria immitis in Canada in 1986; 46% of them responded. Veterinarians reported that 150,989 dogs were blood-tested for microfilariae and 869 dogs were found with heartworm. Another 65 dogs were amicrofilaremic but diagnosed with heartworm disease and one was found with heartworm at necropsy to give the total number diagnosed in 1986 as 935 (0.62%).
Heartworm was reported from Manitoba, New Brunswick, Ontario and Quebec, but most (810) of the cases were from Ontario. South-western Ontario continued to be the primary focus of the infection in Canada. There were 103 cases reported from Quebec, mostly from and around Montreal, and 21 cases from Manitoba, from Winnipeg and surrounding areas. Heartworm was found most frequently in companion dogs over three years of age maintained mainly outdoors in rural areas. About 33% of the cases were observed with clinical signs of heartworm disease and 81% had a history of not having left Canada.
相似文献19.
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Slocombe JO McMillan I 《The Canadian veterinary journal. La revue veterinaire canadienne》1984,25(9):347-350
In late December 1983, 2 800 veterinarians across Canada were sent a questionnaire in order to assess the status of heartworm disease in Canada in 1983 and 26% of them responded. Veterinarians reported that 59 504 dogs were blood-tested to check for microfilariae and 771 dogs (1.30% of those tested) were found with Dirofilaria immitis. Heartworm disease was diagnosed in all provinces except New Brunswick and Newfoundland but most (733) of the cases were in Ontario.
Heartworm disease was found most frequently in companion dogs over three years of age maintained mainly outdoors in rural areas. About 31% of the cases were observed with clinical signs of heartworm disease and 64% had a history of not having left Canada. Southwestern Ontario continues to be the focus of the infection and most of the dogs there had not left the province previously.
相似文献