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1.
《畜牧与兽医》2016,(8):52-54
为了研究使用性控冷冻精液(以下简称性控冻精)进行人工授精对青年奶牛繁殖性能的影响,选择10名输精员和6头公牛性控冻精对1851头青年奶牛随机进行人工授精,第1次人工授精时全部使用性控冻精,返情的母牛分别使用常规精液和性控冻精人工授精,统计分析妊娠率、产犊数、母犊数等繁殖指标。结果表明:性控冻精人工授精后代母犊率显著高于常规精液人工授精后代母犊率(P0.05);不同公牛性控冻精和不同输精人员的人工授精情期受胎率存在差异(P0.05);性控冻精人工授精对青年奶牛流产率、产犊率和犊牛初生重等没有显著影响(P0.05)。青年奶牛第1次人工授精配种适合选择性控冻精,能显著提高后代母犊率。  相似文献   

2.
本研究通过改进人工授精方法、改善奶牛子宫环境、人为激素调解等试验,观察各项措施对奶牛性控精液受胎率的影响。结果表明,奶牛性控精液人工输精以子宫角深部为好;育成牛在发情12~14hN输精受胎率较高,经产牛可酌情延后2~3h,肌注LHIKH—A3以低剂量处理(25μg)的受胎率高;用盐酸环丙沙星100mL经产牛进行子宫投注净化处理后受胎率显著高于对照组。  相似文献   

3.
试验通过比较荷斯坦奶牛常规精液和性控精液人工授精效果、性控精液对青年牛和经产牛人工授精的效果以及改进型输精枪与通用输精枪输精效果,分析了第一情期受胎率。结果表明:采用性控精液受胎率62.2%,采用常规精液人工授精受胎率80%,性控精液和常规精液差异显著(P〈0.05);同用性控精液人工授精,青年牛(受胎率75%)与经产牛(受胎率57.6%)差异显著(P〈0.05);用改进型输精枪第一情期受胎率70%,通用输精枪第一情期受胎率55%,差异显著(P〈0.05)。  相似文献   

4.
奶牛性控冻精应用研究   总被引:4,自引:2,他引:2  
应用奶牛性控冻精进行人工授精,探讨其情期受胎率、母犊率与常规冻精的差别,以及其不同年龄与配母牛、不同输精时间、不同输精部位与情期受胎率之间的关系,为大规模推广应用提供科学依据.结果:1、奶牛性控冻精人工授精的情期受胎率为56.6%(3020/5335),与普通冻精的情期受胎率59.1%(1328/2246)相比差异不显著(P>0.05),奶牛性控冻精的母犊率为93%(1922/2067),极显著高于普通冻精48.8%(63/129)的母犊率(P<0.001);2、应用性控冻精,青年牛的情期受胎率为69.0%(2333/3382),显著高于经产牛49.2%(961/1953)的情期受胎率(P<0.05);与配母牛 发情开始后18~24h输精,其情期受胎率为56.8%(2255/3970),显著高于发情开始后8~12h输精46.1%(629/1365)的情期受胎率(P<0.01):单侧子宫角深部输精,情期受胎率为56.6%(2886/5099),显著高于双侧子宫角输精45.3%(107/236)的情期受胎率(P<0.05).结果表明:1、性控冻精与普通冻精的情期受胎率无差异,可以规模化推广;2、性控冻精输精母牛情期受胎率的高低与母牛的经产与否、输精时间和输精部位有直接相关性.  相似文献   

5.
为了验证流式细胞分离法分离的奶牛X性控冻精与普通冻精生产的F1、F2代繁殖性能是否存在差异,课题组对宁夏平吉堡奶牛场X性控冻精人工授精所生产的F1、F2代的育成牛、经产牛情期受胎率、总受胎率和流产率、死胎弱胎率进行了跟踪检测研究。结果表明:X性控冻精生产的F1、F2代育成牛、经产牛繁殖性能未见异常;X性控冻精生产的F1、F2代育成牛、经产牛与普通冻精生产的后代育成牛、经产牛情期受胎率和总受胎率差异不显著(P0.05)。  相似文献   

6.
本文运用性控冻精进行奶牛人工授精,设计不同输精时间、不同输精部位、不同年龄奶牛间以及合理运用激素调控等因素对奶牛受胎率的影响。结果表明:最佳输精时间在出现明显发情症状后18~22h;最佳输精部位在有卵泡发育一侧子宫角基部;青年牛受胎率要远远高于经产牛,合理运用激素调控有利于提高受胎率。  相似文献   

7.
【目的】试验旨在研究以褪黑素和地诺前列腺素组成的复合添加剂对奶牛性控冻精解冻后精子质量及奶牛人工授精后受胎率的影响。【方法】30份奶牛性控冻精样均分为2组:试验组和对照组,试验组添加由24 ng/mL褪黑素、1.5 mg/mL地诺前列腺素及精液稀释液组成的250 μL复合添加剂,对照组添加250 μL精液稀释液,试验组和对照组均与解冻后的奶牛性控冻精按照1∶1(V/V)进行混合,室温孵育0、2及4 h,通过免疫荧光染色分析精子活率、顶体完整率、高能线粒体活性精子比率;对216头青年奶牛和82头头胎奶牛输精后通过28 d早孕检测来确定受胎率情况。【结果】与对照组相比,经复合添加剂处理0 h的性控冻精活率、顶体完整率及高能线粒体活性精子比率均无显著变化(P>0.05);经复合添加剂处理2 h的性控冻精活率、顶体完整率、高能线粒体活性精子比率均显著升高(P<0.05);经复合添加剂处理4 h的性控冻精活率和顶体完整率均无显著变化(P>0.05),高能线粒体活性精子比率显著升高(P<0.05)。在输精试验中,试验组青年奶牛和头胎奶牛中的受胎率分别为65.22%和48.21%,均显著高于对照组(P<0.05)。【结论】以褪黑素和地诺前列腺素组成的复合添加剂可以促进解冻后奶牛性控冻精精液品质以及青年奶牛和头胎奶牛输精后的受胎率。  相似文献   

8.
应用奶牛性控冻精进行人工授精,探讨不同冻精品种、不同配种员、不同输精部位、不同发情状态、配次等因素对情期受胎率的影响,结果表明,冻精品种、配种员技术水平、输精部位对性控冻精受胎率均有影响,其中输精部位对性控冻精受胎率影响更显著。另外,本文也探讨了解决性控冻精受胎率制约性因素的对策。  相似文献   

9.
试验观测对比奶牛性控冻精和常规冻精解冻后精子存活时间,为进一步把握输精时间,提高受胎率提供依据。试验结果表明:性控冻精刚解冻时活力较高,为0.5级以上,但活力下降快、存活时间较短,解冻后6h活力降低为零;常规冻精刚解冻时活力在0.4~0.5级之间,但存活时间较长,活力下降速度慢,解冻后8h活力降低为零。所以性控冻精解冻后,要求输精技术员尽快输精。  相似文献   

10.
冷冻精液人工授精与鲜精人工授精和本交相比,其受胎率较低.影响冷冻精液质量的因素主要是①稀释液成分的影响,包括稀释液的组成成分及其比例分配.②稀释液中温度变化的影响.③稀释倍数和甘油含量的影响.精液稀释比例越小,甘油含量就越小,精子受的损伤就越小.④精液解冻的影响.小体积的冻精可以快速解冻,而以毫升计包装的冻精则不宜快速解冻.  相似文献   

11.
Our aim was to investigate insemination techniques in order to improve pregnancy rates of artificial insemination (AI) using sex-sorted semen (sexed AI) in cattle in tropical and subtropical (T/ST) regions. In T/ST regions, the pregnancy rates by sexed AI are reportedly the lowest in the hottest months of the year, with less than 15% in cows and 35–40% in heifers (PMID 24048822). We compared sexed AI by depositing the semen into the uterine body (UB-AI, n = 12) versus the unilateral uterine horn (UUH-AI, n = 14) of pre-ovulation heifers. The ovary and follicle were assessed by rectal ultrasound before AI. After insemination, pregnancy was determined by ultrasound at approximately 40 days and approximately 70 days. In the present study, we demonstrated that high pregnancy rates (>70%) by sexed AI in the hottest season in a subtropical region such as Taiwan can be achieved when heifers with pre-ovulation follicles are used. The overall pregnancy rates were 54% higher in the UUH-AI (71%) group than in the UB-AI (42%) group (P = 0.06), examined on approximately 40 days post-sexed AI. Surprisingly, however, the pregnancy outcome appeared to be higher in the hot season (62%) than in the cool season (46%) although this difference was not statistically significant. Based on the present study, we recommend that cattle breeders perform UUH-AI using sex-sorted semen for heifers with pre-ovulation follicles in order to achieve satisfactory pregnancy outcome in the hot seasons in T/ST regions.  相似文献   

12.
The present study was performed to test fertility in single‐ovulating and superovulated dairy heifers after insemination with low dose sex‐sorted sperm under field conditions. Some parameters, including the dosage, deposition site and timing, were assessed with the pregnancy rates after artificial insemination (AI). Moreover, the use of oestrus synchronization in combination with sorted sperm was evaluated. Besides that, we also improved the embryo production efficiency in superovulated dairy heifers by optimizing the timing of inseminations and repartitioning the sexed sperm dosage among multiple inseminations. The conception rate (52.8%) in heifers after low dose (2 × 106) insemination with sorted sperm deep into the uterine horn did not differ (p > 0.05) from that (59.6%) of conventional AI (1 × 107 non‐sorted sperm) and that of deep insemination with low dose non‐sorted sperm (57.7%). There was also no difference (p > 0.05) between conception rates after single (51.7%) and double (53.8%) deep insemination with sorted semen. Heifers inseminated with sorted sperm at synchronous oestrus had a lower pregnancy rate (48.1%) than heifers at spontaneous oestrus (53.6%), but this did not reach statistical difference (p > 0.05). The average number of transferable embryos collected in vivo from heifers inseminated with sorted sperm (4.81 ± 2.04) did not differ (p > 0.05) from that obtained from heifers after insemination with non‐sorted sperm (5.36 ± 2.74). Thus, we concluded that the pregnancy rate after deep intra‐uterine insemination with low dose sorted sperm was similar to that of non‐sorted sperm, which was either also deposited at a low dose deep intra‐uterine or into the uterine body. Sychronization of oestrus can be beneficial in combination with sorted sperm to optimize the organization and management of dairy herds. The results from superovulated heifers demonstrated that our insemination regime can be used to obtain a comparable embryo production efficiency with sorted sperm than with non‐sorted sperm.  相似文献   

13.
Artificial insemination (AI) in pigs has been established for about four decades but ejaculates are still used insufficiently. Higher demand of semen for AI and new techniques that involve low sperm concentration require the optimization of insemination protocols. Based on the knowledge of the physiology of sperm transportation and events in the female genital tract prior to fertilization, new strategies are under development to minimize sperm losses. One goal is to deposit the semen into the uterine horn rather than into the proximal cervix. It was shown that the minimal number of spermatozoa necessary for surgical AI at the utero‐tubal junction (UTJ) were at least 1 × 106 diluted in 0.5 ml of a special extender. Artificial insemination into the distal part of the uterine horn required about 1 × 107 million sperm in 20 ml of extender. Meanwhile, first insemination devices for non‐surgical intra‐uterine AI are commercially available. Using similar sperm concentrations as for surgical AI, non‐surgical uterine insemination did not differ significantly from control inseminations in terms of pregnancy rate and litter size. With respect to the fertilizing capacities of their ejaculates, boars have to be selected more strictly for sperm quality parameters as most of the compensatory effects of sperm cells disappear in maximally extended semen samples.  相似文献   

14.

The objective of this study was to evaluate the fertility of sexed semen compared with conventional semen with regard to the puberty and breeding ages of Holstein dairy heifers subjected to double Ovsynch protocol with fixed time of artificial insemination. A total of 468 Holstein heifers were divided into two groups. The first group was 122 dairy heifers inseminated via conventional semen, while the second group was 346 heifers inseminated with sexed semen. The puberty and breeding ages of heifers were determined from the farm records. Estrus was synchronized using the double Ovsynch protocol. Numbers were estimated for pregnancy at 40 and 60 days post insemination, embryonic loss, and abortion. The results revealed that the heifers inseminated with sexed semen had a significantly lower first-service pregnancy rate (51.45%) than those inseminated with conventional semen (61.47%). Heifers achieving puberty before 350 days old had a higher pregnancy rate. Embryonic losses and abortion rates did not differ between the two types of semen. Holstein heifers subjected to Ovsynch protocol with sexed semen had an acceptable first-insemination pregnancy rate. Even the applications of sexed semen reduce the reproductive fertility and pregnancy rate in Holstein heifers.

  相似文献   

15.
The effects of artificial insemination (AI) using sexed sperm on pregnancy rates have seldom been studied in lactating dairy cows on commercial dairy farms. We evaluated pregnancy results after AI of 306 lactating dairy cows, of which 157 were inseminated with 2x10(6) frozen/thawed sexed sperm and 149 with 15x10(6) frozen/thawed unsexed sperm. The average pregnancy and calving rates were 21.0% and 20% for the sexed-sperm AIs and 46% and 45% for the unseparated control-sperm AIs respectively (p<0.001). The proportion of female calves derived from sexed-sperm AI was 82% compared with 49% for control AI (p<0.01). The proportion of live and healthy calves in single births was 100% for sexed-sperm AI and 97% for control AI (p>0.05). Our results indicate that AI with low-dose sexed sperm under field conditions in commercial dairy herds without oestrus synchronization results in significantly reduced pregnancy rates compared with normal-dose AI. Improved insemination strategies combined with increased sperm doses are needed before the use of sexed sperm can be of any significant benefit for the dairy and beef industry.  相似文献   

16.
The aim of this study was to compare pregnancy per artificial insemination (P/AI) after timed AI with sex‐sorted sperm (SS) or conventional semen (CS) in lactating dairy cows. Cyclic cows (n = 302) were synchronized by Ovsynch and randomly assigned into two groups at the time of AI. Cows with a follicle size between 12 and 18 mm and clear vaginal discharge at the time of AI were inseminated with either frozen‐thawed SS (n = 148) or CS (n = 154) of the same bull. A shallow uterine insemination was performed into the uterine horn ipsilateral to the side of probable impending ovulation. Pregnancy per AI on Day 31 tended (p = 0.09) to be less for SS (31.8%) than CS (40.9%). Similarly, P/AI on Day 62 was less (p = 0.01) for cows inseminated with SS (25.7%) compared with CS (39.0%). The increased difference in fertility between treatments from Days 31 to 62 was caused by the greater (p = 0.02) pregnancy loss for cows receiving SS (19.2%) than CS (4.8%). Cow parity (p = 0.02) and season (p < 0.01) when AI was performed were additional factors affecting fertility. Primiparous cows had greater P/AI than multiparous cows both on Day 31 (41.7% vs 25.0% in SS and 53.0% vs 31.8% in CS groups) and on Day 62 (33.3% vs 20.5% in SS and 48.5% vs 31.8% in CS groups). During the hot season of the year, P/AI on Day 31 was reduced (p = 0.01) in the SS group (19.6%) when compared with the rates during the cool season (38.1%). In conclusion, sex‐sorted sperm produced lower fertility results compared to conventional semen even after using some selection criteria to select most fertile cows.  相似文献   

17.
Breeding records, including 649 inseminations during fall and winter at a dairy farm in a subtropical area of Western Mexico (24o N; 24°C, mean annual temperature 24°C) were analyzed to document effects of sex-sorted semen from commercial Gyr bullls, estrus synchronization protocol, inseminator, sire and environmental conditions on fertility of crossbred cows (Holstein × Gyr). Percentage of services resulting in pregnancies decreased sharply when sex-sorted semen was used (22.7 vs. 37.7%; P < 0.01). Although statistically not significant (P = 0.31), cows whose first insemination was in November experienced a numerically greater reduction (21 percentage points) in pregnancy rate compared to cows whose first insemination occurred in December. Substantial increases in services per pregnancy (4.71 ± 1.35 vs. 2.13–2.43; P < 0.01) were associated with the warmer month of the study period, November, compared to other winter months. Pregnancy rates of cows regardless of semen category (33%) were not affected by sire, temperature–humidity index and estrus synchronization protocol. Cows inseminated by one inseminator had higher pregnancy rates (P < 0.01) than cows inseminated by other two technicians. The sorted sperm produced 91% (142/156) female offspring. It was concluded that, under the field conditions of the present study, pregnancy rate with sexed semen was 15 percentage points lower than pregnancy rates using conventional semen, with 91% of female calves derived from sexed sperm.  相似文献   

18.
At the time of AI following Ovsynch protocol, a total of 51 buffaloes were randomly divided in a first group (n = 30) subjected to conventional AI into the uterine body with 20 million non-sex sorted frozen-thawed spermatozoa, while a second group (n = 21) was inseminated near the utero-tubal junction (UTJ) ipsilateral to the ovary carrying the preovulatory follicle with 2.5 million live (4 million total) sex-sorted frozen-thawed spermatozoa. The semen used for flowcytometric sorting was collected and processed on a farm in Italy, and then shipped to a laboratory in Germany. Eleven buffaloes were inseminated with X-chromosome bearing spermatozoa and 10 with Y-chromosome bearing spermatozoa. Conception rates after conventional and UTJ inseminations were 43.3% (n = 13) and 42.8% (n = 9) respectively (p = 0.97). Eight of the nine foetuses obtained after insemination with sexed spermatozoa corresponded to the sex as predicted by the cell sorting procedure (five male and four female foetuses by ultrasound vs six male and three female foetuses by cell sorting). In conclusion, for the first time buffalo semen has been successfully subjected to procedures for flowcytometric sperm sorting and freezing. Low doses of sexed spermatozoa have been deposited near the UTJ giving conception rates similar to those of conventional AI with full dose.  相似文献   

19.
The main objective of this study was to assess the effect of month of breeding on reproduction performance of Holstein heifers and cows inseminated with sex-sorted or conventional semen in a hot environment. Pregnancy per artificial insemination (P/AI; 64,666 services over an 8-year period) both in heifers (n?=?22,313) and cows (n?=?42,353) from a large dairy herd in northern Mexico (26°N) were evaluated with the GENMOD procedure of SAS, with respect to month of AI. Overall, P/AI with sex-sorted semen was greater (P?<?0.01) in heifers (41.6 %) than cows (17.3 %). P/AI for cows serviced with conventional semen was 10 % points higher (P?<?0.01) in January and December (31 vs. 21 %) than cows serviced with sex-sorted semen. While there was no difference in P/AI between the sex-sorted sperm and conventional semen in cows inseminated in July (16 and 18 %, respectively), P/AI plummeted for both groups of cows during the summer and fall (more severe heat stress). P/AI was not different between heifers serviced with sex-sorted or conventional semen during the hottest months of the year (July to October). However, during the coldest month of the year (January and February), P/AI was 10 percentage points greater (P?<?0.01) in heifers serviced with conventional than sex-sorted semen. It was concluded that in this hot climate cow and heifer fertility declined in the summer and fall when inseminated with conventional semen. However, the use of sex-sorted semen during summer and fall did not compromise the breeding success in heifers. Thus, this data suggest that sex-sorted semen promotes some embryonic thermoprotective mechanism, which leads to a marginal summer and fall fertility depression with this type of semen in this particular hot environment.  相似文献   

20.
A new device (Chapingo device) to deposit semen at the base of the uterine horns of cattle was developed at Universidad Autonoma Chapingo, Mexico. Nine Holstein heifers were inseminated by transvaginal laparoscopy, using a laparoscope for cattle and the Chapingo device. A dose of sexed semen (2.1 × 106 spermatozoa) was deposited at the base of the uterine horn ipsilateral to the ovary where the preovulatory follicle was identified. Insemination was achieved in all the heifers, taking on average 13.7 ± 3.1 min per animal. In all cases, it was possible to see both ovaries, the base of the uterine horns and the oviducts. After the procedure, none of the heifers showed any type of complications such as haemorrhage, adhesions or trauma. On days 21 and 22 after insemination, four of the nine heifers (44.4%) returned into oestrus; on day 30 after insemination, one heifer was found to be pregnant by ultrasound. The results show the feasibility of generating pregnancies by transvaginal laparoscopy in heifers inseminated with sexed semen.  相似文献   

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