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《湖南畜牧兽医》2015,(4)
为研究同期发情处理对安化本地水牛繁殖性能的影响,试验分别采用定时输精法、不同激素处理进行同期同期发情处理,并对比青年牛与经产牛对同期发情效果的差异。结果表明:注射Gn RH后18h~20h定时输精和注射Gn RH后观察发情症状适时输精的受胎率为分别为23.53%和37.04%;在同期发情处理后,在第一次配种后注射h CG、LRH-A3或Gn RH,受胎率分别为32.43%、29.17%和38.46%,对照组受胎率为21.05%;青年母牛的同期发情率为51.52%,显著低于经产牛的73.58%,青年母牛和经产牛配种受胎率和总体受胎率分别为47.06%、24.24%和46.15%、33.96%。因此,在安化水牛上适时输精要优于定时输精,第一次配种后注射一定剂量h CG和Gn RH能够提高受胎率,同期发情处理应尽量选择经产牛。 相似文献
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羊同期发情腹腔镜输精最佳时间的研究 《畜牧与饲料科学》2021,42(4):46-48
[目的]确定羊同期发情腹腔镜输精的最佳时间。[方法]选取繁殖机能正常、营养状况良好的适龄母羊,在试验母羊阴道内放置孕酮海绵栓10~14 d,撤栓时肌肉注射250~330 IU/只孕马血清促性腺激素（PMSG）。撤栓后12~24 h开始试情,早晚各1次。按撤栓后时间及发情时间不同分4组进行腹腔镜输精：1组为撤栓后46~50 h输精（n=138）,2组为撤栓后50~54 h输精（n=156）,3组为撤栓后54~58 h输精（n=275）,4组为羊发情后30~36 h输精（n=226）。输精后第40~45天进行B超检查,计算各组母羊受胎率。[结果]发情后30~36 h输精的母羊（4组）受胎率最高,为97.79%,其次为撤栓后50~54 h输精的母羊（2组）,受胎率为97.44%,撤栓后46~50 h输精的母羊（1组）受胎率为91.30%;撤栓后54~58 h输精的母羊（3组）受胎率最低,为89.82%。[结论]采用同期发情配合腹腔镜输精技术进行母羊人工授精,最佳输精时间为撤栓后50~54 h以及母羊发情后30~36 h。 相似文献
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以杜湖杂交一代空怀母羊为试验动物,采用CIDR+PMSG+PG法进行同期发情和定时输精,研究PMSG剂量、母羊经产与否、同期发情处理季节对绵羊定时输精效果的影响,旨在为提高绵羊定时输精效果提供参考依据。结果表明:在同期发情处理过程中注射330 IU PMSG组的情期受胎率(81.5%)显著高于250 IU PMSG组(70.0%)(P<0.05);初配羊的情期受胎率(85.2%)显著高于经产羊(75.8%)(P<0.05);在秋季进行同期发情处理羊的情期受胎率(81.6%)显著高于春季组(70.7%)(P<0.05)。说明PMSG剂量、母羊经产与否,以及同期发情处理的季节,均对绵羊定时输精效果具有显著影响。 相似文献
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文章对塔里木马鹿同期发情人工授精技术进行探索和总结,在繁殖季节采用阴道栓+PMSG法同期发情,PMSG剂量为400～500I U,最佳输精时间在发情后8～10小时,1次定时输精在撤栓后61～63小时输精受胎率较高,最佳输精部位为子宫体中部。 相似文献
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为了提高半舍饲条件下西门塔尔杂交牛(西杂牛)同期发情率及情期受胎率,试验选择适繁西杂牛85头,采用孕酮阴道栓(CIDR)结合前列腺素进行同期发情和适时输精,并对不同种类前列腺素(律胎素、氯前列烯醇)进行同期发情效果比较;另外还选择适繁西杂牛133头,分别进行CIDR结合前列腺素适时输精与促性腺激素释放激素(GnRH)定时输精,对情期受胎率进行比较。结果表明:采用CIDR结合前列腺素进行同期发情适时输精时,使用律胎素效果优于氯前列烯醇,二者差异极显著(P0.01);采用GnRH定时输精情期受胎率高于采用CIDR结合前列腺素同期发情适时输精,无显著差异(P0.05)。说明采用CIDR结合前列腺素进行适时输精时选择律胎素同期发情效果明显;采用GnRH定时输精总受胎率高于CIDR结合前列腺素适时输精,而且定时输精不需要观察发情,输精时间固定,便于有计划安排生产,更适于在规模化生产中应用。 相似文献
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为了克服子宫颈输精的不足,提高母羊繁殖率,本试验借助腹腔镜技术,采用腹壁穿刺的方法,通过专用输精枪将肉羊细管冷冻精液输入母羊的子宫角内。试验结果表明,母羊同期发情后48~52 h输精,4个试验羊场受胎率分别为73.6%、71.9%、68.5%、32.7%,说明多胎羊受胎率高于单胎羊,年龄与胎次相仿母羊群受胎率高于胎次不清母羊群。在同等饲养条件下自然发情(试情)与同期发情,母羊受胎率分别为61.3%和60.9%,二者受胎率没有差异。 相似文献
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冷冻精液输精深度和时间对蒙古羊受胎率的影响 《畜牧与饲料科学》2021,42(5):108-111
[目的] 研究冷冻精液输精深度和时间对蒙古羊受胎率的影响。[方法] 选取体况健康、繁殖机能正常的蒙古羊母羊作为试验动物,采用孕酮海绵栓对受体母羊进行同期发情处理。应用常规人工输精法（n=135）、过子宫颈输精法[过子宫颈第一皱褶（1~2 cm）输精（n=120）,过子宫颈第二到第三皱褶（3~4 cm）输精（n=120）]、腹腔镜辅助子宫内输精法（n=128）对发情后的母羊进行冷冻精液人工授精。接受常规人工输精法和过子宫颈输精法处理的受体母羊在发情后约14 h和22 h各输精1次,接受腹腔镜辅助子宫内输精法处理的受体母羊在发情后30~36 h输精1次。输精后40 d用B超仪检测母羊妊娠情况,计算并比较接受不同输精方法处理母羊的受胎率。[结果] 腹腔镜辅助子宫内输精法的受体母羊受胎率平均值最高,为60.2%;其次为过子宫颈第二到第三皱褶（3~4 cm）输精,受胎率平均值为58.3%;过子宫颈第一皱褶（1~2 cm）输精和常规输精法的受体母羊受胎率平均值分别为37.5%和36.3%。统计学分析表明,腹腔镜辅助子宫内输精法和过子宫颈第二到第三皱褶（3~4 cm）输精的受体母羊受胎率平均值显著（P<0.05）高于常规输精法和过子宫颈第一皱褶（1~2 cm）输精。[结论] 蒙古羊母羊发情后30~36 h采用腹腔镜辅助子宫内输精法完全穿刺子宫颈输精1次,可获得比常规输精法更高的受胎率;采用过子宫颈输精法在母羊发情后约14 h和22 h各输精1次,当授精深度接近4 cm时可达到与腹腔镜辅助子宫内输精法接近的受胎率。 相似文献
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[目的]新疆褐牛是新疆北疆牧区养牛业主导品种,夏季放牧区新疆褐牛人工授精集中冷配点模式的广泛推广,对新疆褐牛选育提高和新品系培育起到了积极作用,为探索新疆褐牛同期发情和同期排卵—定时输精最佳处理方法。[方法]试验选用2胎以上45头牛,分3组,A组,PG+PG法;B组,PG法;C组,CIDR+PG法,比较3种同期发情处理方法效果,同时选用2胎以上20头牛,分2组,D组,GnRH+PG+GnRH+AI法;E组,CIDR+GnRH+PG+GnRH+AI法,比较2种同期排卵—定时输精方法效果。[结果]结果表明,3种不同同期发情处理方法母牛集中在12～24 h内发情,其中12～24 h内A组和C组处理方法母牛发情率极显著高于B组处理方法(P0.01),C组比A组高出32.3%,B组和C组母牛总发情率差异不显著(P0.05),A、B、C 3组总发情率分别达到86.7%,40.0%,93.3%;发情母牛经人工授精配种后,情期受胎率3组差异不显著(P0.05)。2种同期排卵—定时输精方法中,E组发情牛排卵率显著高于D组,D组和E组总受胎率差异不显著(P0.05)。[结论]综上所述,新疆褐牛同期发情处理应采用B组方法,即2次PG法,即降低了成本,有可取得较好的效果;同期排卵—定时输精宜采用D组方法,成本低,且受胎率较好,适宜在牧区集中人工授精冷配点推广。 相似文献
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为了提高奶牛的繁殖力,本试验采取两种不同的给药方法分别对青年母牛和经产母牛进行同期发情处理,并比较研究了发情后不同输精时间对受胎率的影响。结果表明,①两种同期发情的处理方法均取得了较高的同期发情率,方法Ⅱ的处理效果较好,经此法处理的青年母牛和经产母牛的同期发情率分别比方法Ⅰ的处理效果高出3.34和1.67个百分点;②采用两种同期发情处理方法,青年母牛组间和经产母牛组间的同期发情率差异不显著(P>0.05),但两组青年母牛的同期发情率(88.33%、91.67%)均高于经产母牛的同期发情率(85.00%、86.67%)。③青年母牛最佳配种时间为发情后10～12h,而成年母牛最佳配种时间为发情后13～15h。 相似文献
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魏静 《四川畜牧兽医学院学报》2009,(4):28-32
在现代法律秩序中,商会自治规范是制定法的基础和必要的补充,甚至在某些方面替代了制定法;商会自治规范主要包括商会组织规范、行为规范、惩罚规范以及争端解决规范等;其效力仅及于其内部成员;商会自治规范和制定法之间存在冲突,但也存在整合的基础。 相似文献
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本文概述了猪的毛色类型、猪的毛色遗传模式,着重综述了猪毛色基因分子基础的研究进展,指出存在问题并就未来发展方向做了思考。 相似文献
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以国际标准强毒Ｒ株人工感染非免疫产蛋鸡,定时扑杀,分别从鼻窦、眶下孔、气管、肺、气囊、卵巢和输卵管分离ＭＧ,并收集感染鸡所产蛋分离ＭＧ。结果表明,人工感染４８小时后上、下呼吸道及肺已被全面感染,９６小时气囊已被感染,１２０小时输卵管已能分离到ＭＧ,卵巢始终分离不到ＭＧ。人工感染鸡自１４４小时便能在其所产蛋中分离出ＭＧ。药物治疗能在７２小时内消除感染,油乳剂苗则需２４天后逐渐降低蛋内ＭＧ分离率,药物卵内注射、种蛋药浴、高温处理均能杀死卵内ＭＧ,但以研制的种蛋浸泡剂药浴效果为最好。 相似文献
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REASONS FOR PERFORMING STUDY: Centesis of the bicipital bursa using an 8.9 cm long spinal needle has been reported but the alternative of employing a 3.8 cm long hypodermic needle requires validation. OBJECTIVE: To compare the efficacy of 2 different methods of centesis of the bicipital bursa and to evaluate the usefulness of ultrasonographic imaging to determine the location of solution administered when centesis of the bursa is attempted. METHODS: For Trial 1, 6 clinicians, who had no previous experience of centesis of the bicipital bursa, attempted to inject a solution composed of an aqueous radiopaque contrast medium and physiological saline solution (PSS) into the bicipital bursae of 2/12 horses using the previously described distal approach to inject one bursa and a proximal approach to inject the contralateral bursa. The bicipital tendon and bursa were examined ultrasonographically before and after injection; and both shoulders were examined radiographically to identify the location of the medium. In Trial 2, another 6 clinicians, also with no previous experience of centesis, repeated Trial 1, using 6 horses, but the radiopaque contrast medium was mixed with air instead of PSS. RESULTS: Accuracy of centesis using the proximal approach was 39% and that of the distal approach 28%. Ultrasonographic examination of the shoulder allowed the location of solution and air to be accurately predicted in all 12 shoulders examined. CONCLUSIONS: Clinicians who have had no previous experience performing centesis of the bicipital bursa are unlikely to be successful in centesis using either approach. Radiographic examination after injecting a radiopaque contrast medium may be necessary to assess the success of centesis especially if bursal fluid is not obtained during centesis. Injecting air along with the radiopaque contrast medium provides more accurate ultrasonographic confirmation of centesis and better radiographic definition than does injection without air. 相似文献
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Effects of size of ingestively masticated fragments of plant tissues on kinetics of digestion of NDF
Ingestively masticated fragments were collected and sized via sieving. Different sizes of esophageal masticate and ruminal digesta fragments, and ground fragments of larger masticated pieces were incubated in vitro, and undigested NDF remaining at intervals of up to 168 h of incubation was determined. The ruminal age-dependent time delay (tau) for onset of digestion of NDF was positively correlated (P < 0.004) with the mean sieve aperture estimated to retain 50% of the fragments between successive sieve apertures (MRA). Degradation rate of potentially degradable NDF (PDF) and level of indigestible NDF were not related (P > 0.10) to MRA of masticated and ground fragments. Estimates of tau were positively related to MRA, with slopes of bermudagrass < corn silage < ruminal fragments of corn silage. It was concluded that fragment size-, and consequently, ruminal age-dependent onset of PDF degradation of a mixture of different fragment sizes results in an age-dependent rate of degradation of the more rapidly degrading of two subentities of PDF. Models are proposed that assume a tau before onset of simultaneous degradation of PDF from two pools characterized as having gamma-modeled age-dependency and age-constant rates. The ruminal age-dependent pool seems to be associated with the faster-degrading pool, and its rate parameter increases with range in MRA in the population of fragments. Conceptually, the ruminal age-dependent rate parameter for PDF degradation seems to represent a composite of several effects: 1) effects of the size-dependent tau; 2) range in MRA of the population of ingestively masticated fragments; and 3) subentities of PDF that degrade via more rapid age-dependent rates compared with subentities of PDF that degrade via age-constant rates. The estimated fractional rates of ruminative comminution of ingestively masticated fragments (0.060 to 0.075/h) were of a magnitude similar to the mean fractional rates of PDF digestion (0.030 to 0.085/h), which implies that ruminative comminution may be first-limiting to fractional rate of PDF digestion. The in vivo roles of ingestive and ruminative mastication of fragments on PDF degradation must be considered in any kinetic system for estimating PDF digestion in the rumen. These results and others in the literature suggest that the rate of surface area exposure rather than intrinsic chemical attributes of PDF may be first-limiting to degradation rate of PDF in vivo. 相似文献