水牛同期发情技术的研究进展

水牛发情不明显和产犊间隔长阻碍了水牛的繁殖效率提高。水牛发情观察困难,所以受胎率也下降。为了提高水牛的繁殖效率,可通过同期发情技术来实现。主要是通过调控黄体（CL）的基础来实现,要么利用前列腺素（PG）诱导未成熟的黄体溶解,或者通过利用孕酮来延长黄体期。本文就应用GnRH、FSH、LH、eCG、hCG、孕酮、雌二醇等激素同期发情方法进行评价,综述了不同同期发情和排卵方法对水牛繁殖的影响。     

水牛同期发情技术的研究进展

水牛发情不明显和产犊间隔长阻碍了水牛的繁殖效率。为了提高水牛的繁殖效率,可通过同期发情技术来实现。本文对应用PGF2α、GnRH、FSH、LH、eCG、hCG、孕酮、雌二醇等激素同期发情方法进行了评价,综述了不同同期发情和排卵方法对水牛繁殖的影响。     

云南水牛同期发情技术的研究

为探讨云南水牛同期发情的效果,于2007～2009年在云南大理、德宏对摩本杂水牛和尼本杂水牛共260头采用CIDR+PG、两次PG法进行了同期发情处理,以期提高云南水牛的同期发情率和冷冻精液人工授精配种受胎率。结果表明:摩本杂和尼本杂水牛经同期发情处理后发情率分别为86.54%和86.81%,冷冻精液配种后受胎率分别为48.89%和49.37%。两者间差异不显著(P0.05)。采用CIDR+PG同期发情处理法的效果无论在同期发情率还是受胎率上都明显好于两次PG法。两者间差异显著(P0.05)。在秋季进行同期发情处理,水牛的同期发情率最高,可达88.71%,明显高于春季的73.17%。在受胎率方面,也是秋季效果要好于春季,两者间差异显著(P0.05)。同期发情和自然发情受胎率方面,同期发情处理的受胎率为45.09%,自然发情受胎率为34.5%,两者间差异极显著(P0.01)。     

利用同期发情技术提高水牛繁殖率的试验

利用同期发情技术提高水牛繁殖率的试验杨绍鹏，康文凯，周贤良（邛崃市畜牧局四川邛崃６１１５３０）前言同期发情的理论研究在６０年代已趋于成熟，美、英、日、法等畜牧业较发达的国家在８０年代初将此技术应用于生产。８０年代末此项技术已在畜牧业发达国家的肉牛饲养...     

水牛同期发情及胚胎移植技术及其应用

同期发情是指采用各种药物对母牛发情周期进行调控,使母牛发情排卵控制在预期范围内。体外胚胎移植是指采集早期胚胎或通过活体采卵技术进行体外受精生产胚胎,然后移植到其他母牛。国外从1989年,国内从1991年开始研究至今,卵母细胞成熟率、卵裂率和囊胚率（占分裂卵数）,     

武宣农村水牛同期发情试验报告

应用前列烯醇、孕马血清处理母水牛进行同期发情.结果表明,301头母水牛中,有发情表现的263头,有效率87.4%;第一情期人工授精263头,受胎68头,情期受胎率25.9%;第二情期复配114头,受胎46头,情期受胎率40.4%;总情期受胎率30.2%,总受胎率43.3%.     

GnRH结合PGF2α法处理水牛同期发情试验

试验应用GnRH结合PGF2α法处理水牛进行同期发情试验的研究,应用于水牛胚胎移植的实践中,并取得较好的效果.为建立最佳的同期发情方法和为胚胎移植的产业化奠定理论和实践基础,现将试验报道如下.     

应用同期发情定时输精提高水牛繁殖率

用国产氯前列烯醇对３６头本地沼泽型水牛，和１３头摩拉杂交水牛，进行激素诱导同期发情和定时人工授精，６０天内配种母牛发情率和配种受胎率是：本地水牛１００％和８６．１１％，杂交水牛１００％和５３．８５％，明显高于同期母牛的自然情率和配种受胎率。     

水牛同期发情技术试验

农村饲养的水牛,一般分散饲养,多为每户1头,母水牛发情不明显,农户对母水牛的发情鉴定有很大的难度,因此很多母牛不能得到及时配种,繁殖率很低。为提高农村母牛的繁殖率,加快农村水牛改良步伐,2003年10月31日,在武宣县禄新乡上堂村,利用同期发情技术,开展水牛人工授精杂交改良的试验。共处理本地母水牛32头,第一情期人工授精29头,受胎8头,情期受胎率27．6％;第二情期复配10头,受胎4头。两情期受胎率41．4％。     

奶牛和水牛同期发情-定时输精技术研究进展

同期发情-定时输精技术是在经典的定时输精技术基础上的延伸以及改良,目前已在全世界范围内广泛使用,可以有效提高牛的繁殖水平,避免因发情延迟或不发情等带来的经济损失。本文总结了近几年国内外在奶牛和水牛同期发情-定时输精技术中对激素配伍和输精时间等方面的改良研究进展,为奶牛和水牛的繁殖育种及相关研究提供参考。     

Effect of estrus synchronization treatment after luteolysis on Holstein heifers as embryo transfer recipients

This study was designed to evaluate the effect of estrus synchronization treatments on recipient heifers for embryo transfer (ET). Holstein heifers were separated into the following three groups: (i) an administration of 50 µg GnRH (gonadotropin‐releasing hormone) analog was given to heifers at a random stage of the estrus cycle, followed 7 days later by two administrations of 7.5 mg prostaglandin F2 alfa analog (PG) as control; (ii) another administration of 100 µg GnRH was given to the control group at 48 h after the administration of PG as the second GnRH group; and (iii) an administration of 0.75 mg estradiol benzoate (E2) was given to the control group at 24 h after the administration of PG as the E2 group. Each method caused estrus synchronization. Fresh embryos were nonsurgically transferred into the suitable recipients that had a functional corpora lutea (CL) 7 days after estrus. The E2 group showed a significantly higher (P < 0.01) rate of estrus synchronization (98.9%) at 1–3 days after PG administration and the final pregnancy rate of the E2 group (50.6%) was also significantly higher than the other groups (37.1%, P < 0.05 and 30.9%, P < 0.01, respectively). These findings demonstrate that E2 administration 24 h after PG protocol is effective for estrus synchronization of Holstein heifers, thus improving the productivity of ET.     

应用体细胞克隆技术和胚胎移植技术生产克隆水牛

为了解决克隆水牛技术在供核细胞、受体细胞中的选用问题,探索不同条件对移植受孕的影响,完善克隆技术的理论体系。试验以摩拉奶水牛的耳成纤维细胞作为供核细胞,本地水牛卵母细胞为受体胞质进行细胞克隆构建重组胚胎;将发育5～10 d的重组胚胎移植于本地水牛、杂交水牛的子宫内,观察不同发情方式、胚胎类型、胚龄及季节对移植受孕的影响。结果表明:水牛的克隆胚胎妊娠率较低,分别为12.05%、12.04%、13.95%。自然发情和同期发情对克隆胚胎移植受胎率的影响差异不显著;鲜胚胎移植186头,受胎22头,受胎率为11.83%(22/186);冻胚胎移植174头,受胎23头,受胎率为13.22%(23/174)。克隆水牛从出生至12月龄体尺增长明显高于本地水牛;水牛克隆胚胎移植受胎在秋季最好,秋季受胎数占全年的53.33%,显著高于其他季节。     

甘肃马鹿同期发情效果初步研究

将45头甘肃马鹿均分为3组,应用氯前列烯醇(PG)和孕马血清促性腺激素(PMSG)进行同期化处理,处理A组其处理程序为PG+PG+PMSG,处理B组其处理程序为PG+PMSG。结果表明:A、B组5d内的同期发情率(分别为93·3%和86·7%)均高于对照组(P<0·05),但2个处理组间差异不显著(P>0·05);产仔率分别为73·3%和60·0%,比对照组分别提高20%和6·7%,其中A组的双仔率为6·7%;产仔日期比对照组分别缩短了12d和8d。处理组仔鹿的平均初生重也比对照组提高1·53kg,而且A、B2组仔鹿的断奶成活率也比对照组分别提高了2·5和12·5个百分点。总体而言,A组效果较好。     

光照与药物对母兔同期发情影响的研究

为了研究光照与药物控制同期发情对母兔窝产仔数的影响，试验选用150日龄体质相近的父母代伊拉母兔80只，随机分为2组，每组40只。试验组连续7d人工光照后人工授精繁殖；对照组自然光照，注射孕马血清促性腺激素（PMSG）后人工授精繁殖。结果表明：经168d，2种方法对母兔窝产仔数影响不大，经t检验，平均窝产仔数和平均窝产活仔数差异不显著（P〉0．05），说明光照控制母兔同期发情技术完全能应用到商品肉兔的繁殖生产中。     

乏情季节诱导山羊同期发情的研究

通过对云阳县栖霞乡放牧 +舍饲条件下的经产母羊 3组 (A组 40只、B组 3 1只、C组 18只 )共 89只分别用孕激素阴道栓同期发情处理 10天 ,其中A组取栓后直接观察发情情况、B和C组取栓后分别注射PGF2α 0 0 5mg/只和 0 1mg/只。结果表明 :A组 2～ 4天内同期发情率为 42 5 0 % ;B组同期发情率为 67 74% ,48小时有羊只发情高峰 ;C组同期发情率为83 3 3 %。取栓至开始发情时间A组明显长于B组和C组 (P <0 0 5 ) ;平均发情持续时间短于B、C组 (P <0 0 1,P <0 0 5 ) ,B、C组之间差异不显著 (P >0 0 5 )。     

Full-term delivery of river buffalo calves (2n = 50) from in vitro-derived vitrified embryos by swamp buffalo recipients (2n = 48)

Field trials were carried out on the use of swamp buffaloes (2n = 48) as recipients of in vitro-derived vitrified river buffalo (2n = 50) embryos. River buffalo embryos were produced through a total in vitro production system using frozen semen from a top progeny-tested bull and slaughter-house-derived ovaries and cryopreserved by a vitrification technique. Recipient swamp buffaloes were Philippine carabaos selected on body condition, parity, and reproductive status and owned by village farmers. Eighty post-warmed riverine embryos were transferred non-surgically to 40 swamp buffalo recipients, of which three healthy riverine calves were born by normal delivery and one stillbirth, representing a 5.0% (4/80) full-term development and 10% (4/40) calving rate with 75% (3/4) normal and 25% (1/4) stillbirth. The results demonstrate that, under field conditions and despite the difference in chromosome number between the embryo and recipient, swamp buffaloes are potential surrogate mothers of imported, genetically superior river buffalo frozen embryos. Thus, embryo IVP-vitrification and transfer technology is a potential tool in the propagation of genetically superior buffaloes. Precautionary measures, however, are recommended to avoid dystocia and stillbirth.     

Post-thaw development of in vitro produced buffalo embryos cryopreserved by cytoskeletal stabilization and vitrification

The present study was conducted to examine post-thaw in vitro developmental competence of buffalo embryos cryopreserved by cytoskeletal stabilization and vitrification. In vitro produced embryos were incubated with a medium containing cytochalasin-b (cyto-b) in a CO₂ incubator for 40 min for microfilament stabilization and were cryopreserved by a two-step vitrification method at 24℃ in the presence of cyto-b. Initially, the embryos were exposed to 10% ethylene glycol (EG) and 10% dimethylsulfoxide (DMSO) in a base medium for 4 min. After the initial exposure, the embryos were transferred to a 7 µl drop of 25% EG and 25% DMSO in base medium and 0.3 M sucrose for 45 sec. After warming, the embryos were cultured in vitro for 72 h. The post-thaw in vitro developmental competence of the cyto-b-treated embryos did not differ significantly from those vitrified without cyto-b treatment. The hatching rates of morulae vitrified without cyto-b treatment was significantly lower than the non-vitrified control. However, the hatching rate of cyto-b-treated vitrified morulae did not differ significantly from the non-vitrified control. This study demonstrates that freezing of buffalo embryos by cytoskeletal stabilization and vitrification is a reliable method for long-term preservation.     

不同冷冻方法对水牛体外生产胚胎冷冻效果的研究

本研究采用不同来源的体外生产胚胎(屠宰场卵巢IVF胚胎,OPU-IVF胚胎,SCNT胚胎),系统研究了不同冷冻方法对水牛体外生产胚胎冷冻效果的影响,以完善水牛体外生产胚胎冷冻方法,进一步提高胚胎冷冻效果。试验选用6～7日龄囊胚分别用不同的冷冻液和不同冷冻方法进行胚胎冷冻。玻璃化冷冻液分别为40%EG、25%EG+25%DMSO和20%EG+20%DMSO+0.5 mol/L蔗糖;程序化冷冻液分别为10%甘油和0.05 mol/L海藻糖+1.8 mol/L EG+0.4%BSA。结果表明:(1)在玻璃化冷冻中,无论何种胚胎不同冷冻液的冷冻效果有明显的差异,但均以20%EG+20%DMSO+0.5 mol/L蔗糖作为冷冻液的冷冻效果最好,并且高于程序化冷冻的存活率;而对于程序化冷冻,用10%甘油作为冷冻液,屠宰场卵巢IVF胚胎的冷冻后存活率略高于用0.05 mol/L海藻糖+1.8 mol/L EG+0.4%BSA的冷冻后存活率,但差异不显著(P>0.05)。(2)VF胚胎利用程序化冷冻胚胎解冻后,在0～24 h内有76.5%胚胎复活,高于玻璃化冷冻的复苏率(48.9%)(P<0.05);而与此相反,在24～48 h内,玻璃化冷冻胚胎的复苏率(42.6%)则高于程序化冷冻(23.5%)(P<0.05)。综上所述,各种来源的水牛体外生产胚胎均可进行冷冻保存,应用玻璃化冷冻的效果好于程序化冷冻,且以20%EG+20%DMSO+0.5 mol/L蔗糖作为冷冻液进行玻璃化冷冻效果最好,但程序化冷冻后的胚胎复苏速度明显快于玻璃化冷冻的速度。     

Intravaginal administration of estradiol benzoate capsule for estrus synchronization in goats

Estrus synchronization requires multiple treatments of hormonal drugs, requiring considerable time and cost. The aim of the present study was to develop an estrus synchronization protocol using intravaginal administration of estradiol benzoate (EB) capsules in goats. Two types of capsules were prepared: an EB capsule that melted immediately after administration and a sustained-release (SR) EB capsule that dissolved slowly and reached a peak after 24 h. Goats with functional corpus lutea were intramuscularly treated with prostaglandin F_2α (PG). At 24 h after PG administration, goats were administered 1 mg of EB solution intramuscularly (PG + 24IM; n = 6) or 1 mg of EB capsule intravaginally (PG + 24EB; n = 6). The SR EB capsule was administered intravaginally at the time of PG administration (PG + SR; n = 6). The control group (n = 6) received only PG. All groups showed estrus within 72 h after PG administration. The onset of estrus did not differ significantly between the PG + 24IM and PG + SR groups but was earlier than in the control group. Estradiol concentration in the PG + SR group peaked at 11.5 ± 6.1 h after EB and PG administration. Peak estradiol concentrations were not significantly different between the PG + 24IM and PG + SR groups (78.0 ± 25.8 and 64.0 ± 38.1 pg/ml, respectively), and were higher than the PG + 24EB and control groups (27.3 ± 8.8 and 14.6 ± 6.1 pg/ml, respectively). These results suggest that intravaginal administration of an EB capsule with a sustained-drug release base is applicable for estrus synchronization, as an alternative to intramuscular administration.     

水牛体细胞连续核移植的效果

为探讨水牛体细胞连续核移植的效果,以水牛胎儿成纤维细胞为核供体,进行了水牛体细胞连续核移植。结果显示,连续核移植的融合率显著高于原代核移植(87.9%vs76.2%,P<0.05),但两者之间的分裂率和囊胚率没有显著差异(P>0.05);这说明水牛体细胞核移植胚胎可被再次克隆而不降低其发育能力,水牛体细胞连续核移植是可行的。