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1.
随机选择自然发情的母牛900头,其中黄牛450头,水牛450头,采用冷冻精液和新鲜精液进行人工授精,观察不同输精部位对母牛配种受胎率的影响。试验结果表明,①冷冻精液组:采用子宫颈内输精,配种受胎率黄牛和水牛均为0;采用子宫颈与子宫体交界处输精,配种受胎率黄牛达86.67%,水牛达66.67%;采用子宫体前1/3处输精,配种受胎率黄牛为60.0%,水牛为40.0%;采用子宫颈内5~6 cm处输精,配种受胎率黄牛为26.67%,水牛为6.67%;在子宫体与子宫角交界处输精,配种受胎率黄牛达13.33%,水牛达6.67%;采用子宫颈与子宫体交界处输精,配种受胎率显著高于其他输精部位(P0.01);②新鲜精液组:采用子宫颈内输精,配种受胎率黄牛为46.67%,水牛为13.33%;采用子宫颈与子宫体交界处输精,配种受胎率黄牛为80.0%,水牛为60.0%;采用子宫体前1/3处输精,配种受胎率黄牛为66.67%,水牛为33.33%;采用子宫颈内5~6 cm处输精,配种受胎率黄牛为33.33%,水牛为20.0%;采用子宫体与子宫角交界处输精,配种受胎率黄牛和水牛均为13.33%。同样表明采用子宫颈与子宫体交界处输精,配种受胎率显著高于其他输精部位(P0.01),为母牛输精的最佳输精部位。  相似文献   

2.
为探索精液剂型、输精部位对母驴情期受胎率的影响,试验在母驴发情旺季(3—6月份)选取健康母驴300头随机分组,分别采用3种精液剂型(冷冻精液、4℃冷却精液、鲜精)和2个不同输精部位(子宫颈内口、子宫角深部)进行人工授精,并对其受孕情况进行统计和分析。结果表明:冷冻精液、4℃冷却精液、鲜精人工授精的情期受胎率分别为23.88%、29.67%、35.28%,其中鲜精受胎率最高,与冷冻精液之间差异显著(P0.05);子宫颈内口和子宫角深部输精的情期受胎率分别为33.33%、45.16%,组间差异不显著(P0.05),但后者的受胎率略高。说明采用鲜精剂型、子宫角深部输精的方式可以更好地提高母驴情期受胎率。  相似文献   

3.
本文针对水牛的发情特点、适时输精、输精部位、输精次数、以及外源激素对配种受胎率的影响进行探讨。结果:①水牛发情持续时间变化范围比较大,可以从1天至几天不等,发情特征性表现不如黄牛明显,大部分水牛在发情后36~40h即进入发情的后期或末期,平均40h左右输精受胎率可达61.9%,效果最好,24h以前、60h以后输精,受胎率分别为25.7%和32%,效果不理想;②在子宫颈与子宫体交界处,配种受胎率达63.1%,分别比子宫颈内、子宫体前1/3、子宫体与子宫角分叉处输精高出60、21.1和57个百分点,差异显著(P<0.01),为最佳输精部位;③水牛发情时进行2次输精受胎率达65.3%,比1次输精高出26.1个百分点,差异显著(P<0.01);④水牛发情后24h、36h、48h用HCG、LRH-A3处理后,配种受胎率分别为65.7%、71.1%和68.6%,分别比对照组高出43.8、7.8和16.2个百分点以上,差异显著(P<0.01)。  相似文献   

4.
在几年来的配种工作实践中,我们在采用直肠把握子宫颈输精法进行黄牛冻精配种的基础上,初步探索了子宫体输精,即把精液直接输到母牛子宫体内,取得了比较满意的受胎效果,用这种方法输精,准胎率达到88.7%,比子宫颈管输精法提高10%以上。我们从1977年开始应用冷冻精液改良黄牛,当时采用开腔器输精法,由于输精部位浅,开膣器刺激母牛生殖道,引起努责、弓腰,造成精液逆流,影响受胎,加  相似文献   

5.
黄牛最佳输精部位的研究   总被引:1,自引:0,他引:1  
本试验于1999—2001年对黄牛的最佳输精部位进行研究,每年从建三江分局七星农场选择160头可繁本地母牛,均分成4组对其输精,输精部位分别为:子宫颈5—8cm处,受胎率为75%;子宫体分叉处,受胎率为77.5%;精液一半输到卵泡发育较好的一侧子宫角,一半输至另一侧子宫角;受胎率为79.17%;全部输入卵泡发育好的一侧子宫角,受胎率为84.17%。上述研究表明,将全部精液输到卵泡发育好的一侧子宫角其情期受胎率最高。  相似文献   

6.
母牛子宫不同部位输精的受胎效果观察   总被引:1,自引:0,他引:1  
在给母牛输精时,一般要求在子宫颈内口前端进行输精,但在操作时,经常发现初配母牛在输精上有困难,达不到该输精部位,而造成对部分牛不敢输精而延误情期.为了提高初配母牛受胎率,对不同母牛分别采取了子宫颈浅部输精、子宫颈内口前端输精和偏角深部输精3种方法.通过268头不同情况发情母牛输精试验,取得了良好的受胎效果.  相似文献   

7.
为探索澳洲白种公羊不同精液剂型、不同输精部位对湖羊母羊受胎率的影响,在春夏季节选择体格健壮、无繁殖疾病、2岁左右的经产湖羊母羊2 431只,随机分组,分别采用冷冻精液(Ⅰ组)、4℃冷却精液(Ⅱ组)、鲜精(Ⅲ组)3种精液剂型和阴道底部(Ⅳ组)、子宫颈内口(Ⅴ组)、腹腔子宫角(Ⅵ组)3个输精部位进行人工授精,并对母羊受孕情况进行统计与分析。结果显示:①在精液剂型方面,Ⅰ组、Ⅱ组、Ⅲ组的情期受胎率分别为66.5%、80.3%、87.8%,组间均呈极显著差异(P<0.01);母羊受胎率分别为88.7%、95.4%、98.3%,Ⅰ组与Ⅱ组、Ⅲ组间呈极显著差异(P<0.01),但Ⅱ组与Ⅲ组间呈显著差异(P<0.05)。②在输精部位方面,Ⅳ组、Ⅴ组、Ⅵ组的情期受胎率分别为72.9%、86.4%、95.1%,组间呈极显著差异(P<0.01);母羊受胎率分别为91.8%、98.7%、99.2%,Ⅳ组与Ⅴ组、Ⅵ组间均呈极显著差异(P<0.01),但Ⅴ组与Ⅵ组间无显著性差异(P>0.05)。说明采用鲜精剂型、子宫角输精的方式可以更有效地提高湖羊母羊的情期受胎率,但从经济效益上综合考虑,最佳的人工授精方式是通过母羊子宫颈内口输入鲜精剂型。  相似文献   

8.
近些年,随着农牧业产业结构不断调整,广西象州县牛养殖产业不断发展,农民群众依靠养牛走上了发家致富的道路。在牛养殖过程中,母牛受胎率不高一直是影响养殖场效益的主要因素,基于此笔者结合实际,以黄牛为研究材料,分别就子宫颈内口处、子宫体分岔处以及子宫角大弯内进行人工输精,观察母牛受胎率情况,为以后提高母牛受胎率积累经验。  相似文献   

9.
所谓母牛的“三点一式”输精,即为在母牛的子宫体,左、右子宫角各输入每次输精量的三分之一。这对于初学者来说难度较大,对于熟练操作者就易把握。我省从1973年开始进行牛的冷冻精液人工授精,采用直肠把握子宫颈深部输精法为发情母牛授精。初开展此项工作时,母牛配种受胎率仅为20%-30%。近年来,由于技术操作熟练程度较以前有所提高,母牛受胎率平均在50%左右。在几年前,新疆、北京等地先后采用母牛的“三点一式”输精,母牛受胎率高达85%一90%,在原有基础上大有提高。现就母牛的“三点一式”输精作一些繁殖原理及实施上的分析…  相似文献   

10.
本试验分别向发情母牛子宫颈口内3~4cm、子宫颈内口处、子宫体分岔处、滤泡发育侧的子宫角大弯内4个不同输精部位进行人工授精时,情期受胎率结果为74.55%,78.18%,82.73%,88.18%。表明,距离精子和卵子结合部位(输卵管壶腹部)越近,呈现情期受胎率越高的趋势。尤其滤泡发育侧的子宫角大弯内输精受胎率显著(P〈0.05)高于子宫颈口内3~4cm、子宫颈内口两处。  相似文献   

11.
12.
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   

13.
采用高效液相色谱法测定癸氧喹酯干混悬剂的含量,在2-250μg/mL范围内,峰面积的常用对数与进样量浓度的常用对数呈良好的线性关系,R^2=1(n=5),平均回收率为99.24%~99.51%,RSD在0.05%~0.28%。此方法分析时间短,样品前处理简便、定量结果准确,重现性好,结果满意,为其质量控制提供了依据。  相似文献   

14.
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   

15.
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   

16.
乳酸杆菌作为益生菌广泛用于人和动物.本文综述了乳酸杆菌改善宿主健康的机制.乳酸杆菌可通过产生抗菌物质如乳酸、过氧化氢、细菌素,或者通过竞争营养或肠道黏附位点来抑制致病菌;通过诱导黏附素的分泌或阻止细胞凋亡而增强肠道的屏障功能,从而保护肠道.文章重点讨论了乳酸杆菌表面成分(表面蛋白、脂磷壁酸和肽聚糖)与肠道受体(C型凝集素受体、Toll样受体和Nod样受体),阐述了他们结合后启动免疫调节信号,调控肠道免疫功能以发挥改善健康作用的机制.  相似文献   

17.
为贯彻落实《兽药生产质量管理规范》(简称《兽药GMP》),进一步推动兽药GMP实施进程,我部制定了《兽药生产质量管理规范检查验收办法》,现予公告。本公告自2003年6月1日起施行。附件:兽药生产质量管理规范检查验收办法二○○三年四月十日第一章 总则 第一条 为推动《兽药生产质量管理规范》(以下简称兽药GMP)的实施,规范兽药GMP检查验收工作,制定本办法。 第二条 农业部负责全国兽药GMP管理和检查验收工作;负责制修订兽药GMP检查验收管理规定;负责兽药GMP检查员队伍建设和监督管理工作,负责国际兽药贸易中GMP互认工作。 …  相似文献   

18.
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   

19.
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   

20.
用硝酸和高氯酸消化蜂蜜,使硒游离出来,在微酸性环境下,硒和2,3-二氨基萘(DAN)生成有较强荧光的物质,用环己烷萃取,在激发波长378nm,荧光波长518nm处测定其荧光强度。蜂蜜中硒含量范围:0.10~0.82μg/g。表明:蜂蜜应视为天然富硒营养品。  相似文献   

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