抑制素及其对动物繁殖的影响

抑制素是二聚体糖蛋白激素,是机体分泌的一种能够调节促性腺激素分泌的活性物质,能够提高家畜的排卵率和繁殖力。抑制素抗原免疫可以提前动物发情,有效提高雌性动物的排卵率,对雄性动物生殖功能也起到重要的作用,因而研究抑制素对动物繁殖的影响,对于提高动物的生殖潜力有着很好的应用前景。     

抑制素免疫对动物生殖功能影响的研究进展

抑制素是一种主要由动物性腺分泌的异二聚体蛋白激素 ,它通过选择性抑制垂体促性腺激素 (主要是 FSH)的分泌 ,进而影响动物的生殖活动。而利用抑制素对动物主动或被动免疫 ,可增加排卵率 ,提高繁殖力的独特功能越来越受到人们的重视。本文就近年来有关抑制素免疫对动物生殖功能影响的研究作一综述。1　抑制素的类型在抑制素免疫研究中 ,有 3种形式的免疫原 ,即天然抑制素制剂、合成抑制素肽段和重组型抑制素。1 .1　天然抑制素　主要有牛抑制素 ( b MPI)和羊抑制素 ( o MPI) ,它是用一种单克隆抗体 2 56 H(其具有对牛 3 2 KD抑制素特异…     

抑制素及其对动物生殖机能的影响

抑制素是一种水溶性多肽激素,对动物生殖活动有重要的调控作用,是内源性FSH分泌的调节剂之一,抑制素抗原免疫可以有效的提高雌性动物的排卵率,对雄性动物生殖功能也有重要的作用,这些也正是家畜繁殖力的基础。随着免疫学的发展和免疫技术的进步,抑制素必将大规模用于畜牧生产,比如可制成多胎疫苗以提高家畜的产仔数。因此,研究抑制素对动物生殖机能的影响,对于提高动物的生殖潜力以及对人类计划生育的研究,都具有重要的理论价值和应用前景。     

抑制素对雄性动物生殖的影响

抑制素是一种由雌性动物的卵泡颗粒细胞和雄性动物的睾丸支持细胞分泌的糖蛋白激素。用抑制素或其片段主动或被动免疫以提高母畜的排卵率和产仔数方面的试验国内外已做了很多，并得到了肯定的结果。但其对雄性动物生殖的影响研究得较少。现就从雄性动物抑制素分泌途径、浓度的变化，对FSH水平影响、生殖调节，抑制素免疫对公畜繁殖力的影响及存在的问题加以阐述。     

抑制素主动免疫对山羊繁殖率的影响

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,主要生理作用是特异性地抑制垂体卵泡刺激素(FSH)的分泌。因此,用抑制素免疫可使动物血液中的FSH水平上升,致使排卵数增加。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。研究旨在应用纯化的猪抑制素对山羊进行主动免疫,探讨对山羊排卵率和血浆FSH水平的影响及作用。1材料与方法1.1试验动物选择年龄2~4岁、平均体重为35.6 …     

抑制素免疫的研制进展

抑制素是机体内分泌的一种能够调节促性腺激素分泌的活性物质，通过抑制素免疫中和技术能够解除抑制素对FSH分泌的抑制作用，从而促进排卵，本文对抑制素及其免疫机理，免疫方法，免疫对动物繁殖性能影响的研究进展作一综述。     

抑制素主动免疫对山羊繁殖率的影响

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,…     

抑制素免疫的研究进展

抑制素是机体分泌的一种能够调节促性腺激素分泌的活性物质.通过抑制素免疫中和技术能够解除抑制素对FSH分泌的抑制作用,从而促进排卵.本文对抑制素及其免疫机理、免疫方法、免疫对动物繁殖性能影响的研究进展作一综述.     

家畜卵泡抑制素的研究进展

抑制素 (Inhibin,INH) ,是一种主要由动物性腺 (卵巢的颗粒细胞和睾丸的支持细胞 )分泌的异二聚体糖蛋白激素 ,由两个三硫键连接两个不同的亚单位 (α和 β)构成 ,对垂体促卵泡素FSH的分泌、合成起选择性负反馈调节物作用。卵泡抑制素免疫中和技术能特异性地刺激机体FSH分泌 ,促进配子生成 ,进而提高动物生殖能力。本文主要就家畜卵泡抑制素的研究进展以及其对家畜生殖的影响作一综述。     

抑制素(Inhibin)基因免疫在提高动物繁殖力中的应用

抑制素(Inhibin)是一种由性腺器官分泌的糖蛋白激素,能抑制垂体促卵泡素(FSH)的分泌及卵泡发育。本文主要阐述抑制素基因免疫对动物繁殖力的影响及影响免疫效果的因素。     

抑制素研究进展

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。     

调控畜禽繁殖的激素免疫技术

回顾近30年来国内外畜禽生殖活动的内分泌免疫调控技术的发展,从早期的免疫类固醇激素和抑制素使动物提前进入初情期,促进更多的卵泡发育和提高排卵数,对公畜则提高其精子生成数量;到现在根据携带Inverdale基因母羊具有高繁殖力的原理发展的免疫BMP15或GDF9提高羊排卵数和产羔数的技术。对禽类免疫催乳素或免疫血管活性肠肽VIP抑制催乳素的分泌,可以解决易就巢禽类的就巢性,提高其产蛋性能。而免疫促性腺素释放激素则可以抑制性腺的发育进行“免疫去势”,提高畜禽的生长速度、瘦肉率、饲料报酬并改善肉质。今后内分泌免疫调控技术的研究应该开发具有更高免疫原性的新型基因工程疫苗和简单实用的免疫程序,以便更好地应用于生产实际。     

Fertility in rats immunized with steroid-free bovine follicular fluid

Inhibin is a gonadal hormone that inhibits the release of follicle stimulating hormone (FSH) from the anterior pituitary gland. The objective of this study was to determine whether active immunization of male and female rats against inhibin rich, steroid-free bovine follicular fluid would increase inhibin antibody titre, onset of female puberty, pregnancy rate, litter size, testis weights, testosterone concentration and serum FSH. Immunization of rats with steroid free bovine follicular fluid stimulated production of anti-inhibin antibodies that immunoneutralized endogenous inhibins and increased levels of circulating FSH in immunized males. Inhibin immunoneutralization resulted in early vaginal opening in immunized females compared with controls and pregnancy rates were increased when immunized female rats were mated with immunized males. However, serum testosterone, testis weights and potential litter size remained unchanged. We conclude that methods to immunoneutralize inhibin may have merit as therapeutic procedures to enhance reproductive performance in domestic animals.     

抑制素免疫在动物繁殖中应用的研究进展

抑制素是性腺分泌的一种糖蛋白激素，它具有抑制垂体促卵泡素合成和分泌的作用。抑制素具有免疫反应性，抑制素免疫在提高动物繁殖性能方面有良好的应用前景。作者阐述了抑制素的结构和特性以及抑制素免疫的机理、类型、方法和影响因素及其在畜牧业中的应用。     

Inhibin: Regulation of reproductive function and practical use in females

Inhibins are gonadal glycoprotein hormones selectively and potently inhibiting follicle‐stimulating hormone (FSH) secretion from the pituitary gland. Inhibins are produced mainly by the ovary and are purified from follicular fluid. Inhibins were shown to be produced in two forms through dimeric assembly of an α‐subunit and one of two closely related β‐subunits to form inhibin A (α‐βA) and inhibin B (α‐βB). Although inhibin subunits are expressed in various tissues, the gonads are the major source of circulating inhibins. While inhibins may act as a paracrine or autocrine factor in some tissues, their best understood roles are as endocrine regulators of pituitary FSH. In this review we focus our attention on more recent developments in inhibin research. We describe patterns of inhibin A and B secretion during the estrous cycle. We also review the immunization against inhibin α subunit as a practical method for superovulation. Superovulation has been induced successfully by passive or active immunization against the inhibin α‐subunit in several species such as mice, rats, hamsters, guinea pigs, cows, mares, ewes and goats. Furthermore, several studies have shown that oocytes superovulated with immunization against inhibin α‐subunit have the ability to develop normally, suggesting that inhibin immunization could be used as a practical method for superovulation in a wide range of animal species.     

双拷贝抑制素基因免疫对大鼠卵泡发育、产仔及生殖激素的影响

将90只大鼠随机分为5组,分别注射10μg.100μL-1 pcISI(T1)、50μg.100μL-1 pcISI(T2)、100μg.100μL-1(T3)pcISI、100μg空载体pcMV-S(V)和100μL生理盐水(S),以探讨在不使用免疫佐剂的情况下,不同剂量的双拷贝抑制素pcISI基因免疫对大鼠卵泡发育、产仔和生殖激素的影响。结果表明,加强免疫能提高抗体P/N值,加强免疫后各剂量组平均抗体P/N值大于2,T3组抗体P/N值显著高于T1和T2组(P<0.05)。T3组成熟卵泡数显著高于对照组(P<0.05),且抗体阳性鼠成熟卵泡数比阴性鼠多12.45个(P<0.05)。除了T1组外,其他2个剂量组产仔数和胎盘数均高于对照组(P<0.05)。抗体阳性鼠胎盘数比阴性鼠多5.09个(P<0.05),产仔数比阴性鼠多5.39个(P<0.05)。抑制素pcISI基因免疫大鼠后促卵泡素(FSH)、雌二醇(E2)和孕酮(P4)含量均高于对照组,T3组的FSH含量与对照组差异显著(P<0.05),T3组的E2含量与对照组差异极显著(P<0.01),各剂量组P4含量与对照组差异均不显著(P>0.05)。这些结果说明,在没有免疫佐剂的前提下,双拷贝抑制素pcISI基因免疫可产生抗体,促进FSH分泌和卵泡发育,增加产仔数。本试验条件下100μg.100μL-1是最佳免疫剂量。     

卵泡抑制素与GFP融合基因疫苗免疫对大鼠卵巢和生殖激素的影响

将50只大鼠随机分为5组,分别注射0.2（T1）、0.6（T2）、1g/L（T3）pEGISI,100μg空载体pEGFP-N1（C1）和100μL生理盐水（C2）,以探讨在没有使用免疫佐剂的情况下,抑制素与GFP融合基因疫苗pEGISI免疫对大鼠卵巢和生殖激素的影响。研究结果,加强免疫能提高抗体P/N值,T3组在加强免疫期与对照组差异显著（P〈0.05）;加强免疫第2周时T3组抗体阳性鼠比例达40%,与T1和T2组差异均显著（P〈0.05）。T3组卵巢大小和卵泡数均显著高于对照组（P〈0.05）,但抗体阳性鼠大卵泡数与阴性鼠差异不显著（P〉0.05）。各剂量组促卵泡素和雌二醇均高于对照组,且在加强免疫第2周时T3组与对照组差异显著（P〈0.05）;各剂量组孕酮含量与对照组差异均不显著（P〉0.05）。结果表明,在没有使用免疫佐剂的前提下,抑制素pEGISI基因免疫可产生抗体,促进卵巢发育和FSH分泌。本试验条件下100μg是最佳免疫剂量。     

抑制素α主动和被动免疫对哈萨克羊生殖激素含量的影响

为了研究抑制素α（INHα）主动和被动免疫对哈萨克羊生殖激素含量的影响，本试验在对抑制素α重组质粒表达菌株进行诱导表达的基础上，将经纯化、鉴定的抑制素α重组蛋白免疫接种新疆双峰骆驼，制备驼抗抑制素α多克隆抗体，并对其进行纯化，检测抗体效价，验证抗体的特异性。之后选择3~5岁、发情时间相近并处于间情期的45只成年哈萨克羊随机分为3组，分别作为抑制素α多克隆抗体免疫组（A组）、抑制素α重组蛋白免疫组（B组）及对照组（C组），每隔10 d连续进行3次加强免疫，应用ELISA法检测在绵羊繁殖活动中具有重要功能的5种生殖激素：促卵泡素（FSH）、促黄体素（LH）、孕酮素（P₄）、雌激素（E₂）、抑制素（INH），并检测血液生化指标。结果显示，IPTG的最佳诱导浓度是0.6 mmol/L，在4 h时诱导出产量较高的抑制素α包涵体蛋白，纯化后的抑制素α重组蛋白纯度较高，并具有较好的免疫原性，经进一步验证发现，制备的抑制素α抗体效价为1：512 000，该抗体可与抑制素α重组蛋白特异性结合。说明成功制备了具有免疫原性的抑制素α重组蛋白和高效价的驼抗抑制素α多克隆抗体。免疫后A组LH、P₄含量和B组FSH、LH、P₄、E₂、INH含量与C组相比差异不显著（P>0.05），而A组FSH含量和E₂含量显著高于C组（P<0.05），INH含量显著低于C组（P<0.05）。通过血液生化指标检测发现，抑制素α蛋白和抑制素α抗血清两种免疫制剂免疫后，试验动物均没有出现不良症状。说明两种抑制素α抗原均可对哈萨克羊血液生殖激素的分泌产生良好效果，相比之下抑制素α抗血清免疫效果更佳。     

Inhibin secretion in the golden hamster (Mesocricetus auratus) testis during active and inactive states of spermatogenesis induced by the restriction of photoperiod

Gonadal function in the male golden hamster (Mesocricetus auratus) was investigated during exposure to a short photoperiod condition. Within 3 weeks of exposure to the short photoperiod condition, FSH and testosterone in the plasma significantly decreased, and subsequently immunoreactive (ir)-inhibin significantly decreased. Testicular contents of ir-inhibin and testosterone, and pituitary contents of LH and FSH also significantly decreased by 3 weeks with regression of weight of testes, epididymis and seminal vesicles and sperm head count. Circulating LH varied but not significantly. Thereafter, all reproductive parameters and secretion of LH, FSH, ir-inhibin and testosterone gradually recovered after 17 weeks of exposure even though animals continued to be subjected to the short photoperiod condition. Plasma concentrations of inhibin B and inhibin pro-alphaC were detectable and were significantly decreased after 15 weeks of exposure to the short photoperiod, but their levels were still detectable. Immunopositive reaction of inhibin alpha and betaB subunits was found in Sertoli cells and Leydig cells in the regressed testes of animals subjected to short photoperiod as was also seen in animals before exposure to the short photoperiod. Although the spermatogenic cycle was suppressed like prepubertal animals, the present study showed that the testicular recovery, so-called refractoriness, is functionally different from the developing stage of immature animals, especially with regard to inhibin secretion. The present results showed that changes in FSH preceded changes in inhibin during the regression and recovery phases, indicating that FSH is a major regulatory factor of inhibin secretion in male golden hamsters. The present study also demonstrated that regressed testes still secrete a small amount of bioactive inhibin during exposure to a short-photoperiod condition.     

Leptospirosis in sheep and goats under tropical conditions

Inadequate management practices and poor reproductive performance have been reported as fundamental factors on reducing the levels of productivity in livestock. Different pathogens have been reported in small ruminants' herds/flocks with reproductive failures. The aim of the present study was to review aspects of leptospirosis in small ruminants, mainly its impact on reproduction and consequently on productivity of the herds/flocks under tropical conditions. Leptospiral infection in goats and sheep is common in several countries, and those species can also act as carriers of leptospires. Severe disease is often associated to young animals and is frequently associated to incidental serovars. In contrast, subclinical infection is mainly characterized by reproductive problems, such as infertility, abortion, occurrence of stillbirths, and weak lambs/goat kids. Moreover, laboratorial tests are essential to achieve an accurate diagnosis of the infection. Microscopic agglutination test is the most common indirect test of leptospirosis, being used worldwide. In small ruminants, PCR consists on a recommendable method for diagnosing animals that carry leptospires. Control of leptospirosis in small ruminants involves measures such as the identification and treatment of the carriers and other sources of infection, quarantine in acquired animals, and systematic immunization with commercial vaccines containing the circulating serovars in the herd/flock. Productivity of small ruminant breeding can dramatically increase with adequate sanitary conditions and control of leptospirosis. Immunization of all the animals combined to the treatment of carriers may successfully control the infection and importantly reduce the economic reproductive hazards that are observed under tropical conditions.