Birth of Kids After Artificial Insemination with Sex‐Sorted,Frozen‐Thawed Goat Spermatozoa

Successful sex‐sorting of goat spermatozoa and subsequent birth of pre‐sexed kids have yet to be reported. As such, a series of experiments were conducted to develop protocols for sperm‐sorting (using a modified flow cytometer, MoFlo SX^®) and cryopreservation of goat spermatozoa. Saanen goat spermatozoa (n = 2 males) were (i) collected into Salamon's or Tris catch media post‐sorting and (ii) frozen in Tris–citrate–glucose media supplemented with 5, 10 or 20% egg yolk in (iii) 0.25 ml pellets on dry ice or 0.25 ml straws in a controlled‐rate freezer. Post‐sort and post‐thaw sperm quality were assessed by motility (CASA), viability and acrosome integrity (PI/FITC‐PNA). Sex‐sorted goat spermatozoa frozen in pellets displayed significantly higher post‐thaw motility and viability than spermatozoa frozen in straws. Catch media and differing egg yolk concentration had no effect on the sperm parameters tested. The in vitro and in vivo fertility of sex‐sorted goat spermatozoa produced with this optimum protocol were then tested by means of a heterologous ova binding assay and intrauterine artificial insemination of Saanen goat does, respectively. Sex‐sorted goat spermatozoa bound to sheep ova zona pellucidae in similar numbers (p > 0.05) to non‐sorted goat spermatozoa, non‐sorted ram spermatozoa and sex‐sorted ram spermatozoa. Following intrauterine artificial insemination with sex‐sorted spermatozoa, 38% (5/13) of does kidded with 83% (3/5) of kids being of the expected sex. Does inseminated with non‐sorted spermatozoa achieved a 50% (3/6) kidding rate and a sex ratio of 3 : 1 (F : M). This study demonstrates for the first time that goat spermatozoa can be sex‐sorted by flow cytometry, successfully frozen and used to produce pre‐sexed kids.     

Fertility in Single‐ovulating and Superovulated Dairy Heifers after Insemination with Low Dose Sex‐sorted Sperm

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.     

Apoptosis‐Like Events and In Vitro Fertilization Capacity of Sex‐Sorted Bovine Sperm

This study utilized three staining assays (Annexin V, mitochondrial membrane potential (JC‐1) and TUNEL) for flow cytometric analysis of apoptosis in sex‐sorted sperm from four different bulls (A, B, C and D). Correlations between sperm quality and IVF efficiency were then assessed to determine which assay provided the best prediction of IVF efficiency. The results of the Annexin V assays, as well as measures of viable sperm, early apoptosis, necrotic sperm and mitochondrial membrane potential (?ψm) showed that the sex‐sorted sperm collected from bull A significantly differed from those of the other three bulls (p < 0.05). In addition, the levels of DNA fragmentation in sex‐sorted sperm from bull A were significantly lower than those from bulls B and C (p < 0.05). The percentage of cells reaching the cleavage and blastocyst stages in sex‐sorted sperm from bull A were significantly greater than those from the other bulls (p < 0.05). A significant positive correlation was observed between viable sperm and the percentage of cells at the cleavage or blastocyst stages (p < 0.05). In contrast, a negative correlation was found between early apoptotic sperm and the percentage of cells at the cleavage or blastocyst stages (p < 0.05). In conclusion, these results indicated that the Annexin V assay was the most reliable technique for the prediction of the IVF success of sex‐sorted bovine sperm.     

Pregnancy Rates in Lactating Holstein–Friesian Cows after Artificial Insemination with Sexed Sperm

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.     

奶牛“同期发情-定时输精”技术综述

奶牛发情鉴定在规模化奶牛养殖中是一个难题,容易因发情鉴定不及时而错过配种期,延长产犊间隔,降低繁殖效率。使用同期发情、同期排卵和定时输精技术可以有效地克服这一缺点,提高繁殖效率,便于配种员的操作。本文对同期发情-定时输精技术的原理和国内外在奶牛上的研究作一综述,供奶牛场有关技术人员参考。     

奶牛人工授精受胎率影响因素和提高措施

奶牛人工授精是以人工方法,采用机械手段采集优质种公牛的精液,再经过机械手段将特定处理后的精液输入母牛生殖道的一种生产技术方式。人工授精操作能极大减少种公牛的养殖数量,节约养殖成本,提高优质种公牛的利用效率,加快品种改良进程,促进育种工作的开展。但由于奶牛人工受精是一个侵入性的操作,一旦操作不合理或者各个细节把握不完善,会造成繁殖母牛出现严重的繁殖障碍,降低母牛的受胎率,不利于提高品种改良和扩大养殖效益。该文主要论述奶牛人工受精受胎率的影响因素,提出相应的改进措施。     

奶牛冷冻性控精液的人工授精试验

XY与CRI奶牛性控冻精解冻后精子活力为0.38、0.41,密度为210万个/剂和230万个/剂,常规冻精解冻后精子活力为0.48,密度为1020万个/剂.据试验,室温下性控精液在5～15 min时其活力下降比常规冻精明显,奶牛发情结束前后4 h内的情期受胎率分别为63.3%与70.7%;青年牛2剂/次、1剂/次的受胎率分别为60.71%(17/28),52.63%(10/19),深度输精与宫体输精的受胎率分别为66.66%(18/27),57.14%(20/35).所产后代母犊率达95.91%(47/49).     

奶牛X性控冻精的应用效果试验

奶牛X性控冻精在国内已实现规模化生产,技术趋向成熟,该项技术的推广应用可明显提高奶牛的繁殖效率,加速奶牛育种进程,社会效益和经济效益显著。本试验是使用X性控冻精在奶牛不同阶段应用效果试验。     

低剂量梅花鹿XY精子马花杂交人工授精试验

采用流式细胞分离仪分离的梅花鹿X和Y型冷冻精液与常规冻精对62头3组同期化处理的马鹿进行直肠把握人工授精。结果表明,0.25 mL/支含106个有效精子的X和Y型冻精产仔率分别为43%和37%,而0.25 mL/支含107个有效精子的常规冻精产仔率为55%,X、Y型冻精与常规冻精组间差异显著(P<0.05),所产后代性别比率分别为0∶10,9∶0和5∶6,X、Y型冻精与常规冻精组间差异显著(P<0.05),X、Y型冻精与常规冻精所产后代出生及60 d时的体重差异不显著(P>0.05)。     

奶牛人工授精的优缺点和技术要点

奶牛人工授精技术加速了奶牛品种改良进程,实现了将优秀种公牛精液跨区域、超时限的利用共享,极大地促进了养牛业的发展.以奶牛人工授精应用现状为出发点,介绍了人工授精技术的优点和不足,最后结合自身工作经验,从发情鉴定、适时配种、精液解冻、精液检测、输精、精液保存和妊娠检测等技术要点进行概述,以期更好地促进奶牛人工授精技术的应...     

奶牛性控冻精低剂量人工授精技术规范

奶牛性别控制繁育技术是继常规人工授精和胚胎移植之后,家畜繁育改良技术的第三次革命.由于性控冻精自身特点,在人工授精操作上与常规冻精输精略有不同,为了提高奶牛性控冻精受胎率和利用效率,节省成本,本规程对奶牛性控冻精低剂量深部人工授精技术环节进行了规范和要求.     

临沂市奶山羊鲜精人工授精技术应用

临沂市具有较好的农业资源,适合发展奶山羊养殖业。但是,目前奶山羊传统的自然交配繁育速率较慢,且受胎率低,不利于奶山羊养殖业的快速发展。近年来,由于人工授精技术具有增强繁殖速率、提升受胎率、提高种公羊利用率和降低成本等优点,在畜牧养殖业中的运用和推广十分广泛。但是人工授精的成功率受到母羊发情期、精液采集和保存、输精方式等多种因素的影响,因此增强对该技术的了解,对促进当地奶山羊的良种繁育具有重要意义。     

奶牛性控冻精和常规冻精活力对比试验分析

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。     

不同胎次奶牛应用性控冻精的效果观察

本文探讨了不同胎次奶牛应用性控冻精人工授精的效果。观察了不同胎次奶牛使用性控冻精后的情期受胎率、流产率、正产胎儿成活率、产母犊率、产公犊率和正产胎儿死亡率。结果表明,情期受胎率、正产胎儿成活率和母犊率随着胎次的增加而呈下降趋势（P〈0．05）,而流产率、产公犊率和正产胎儿死亡率随着胎次增高而逐渐增加（前一项P〈0．05,后两项P〈0．01）。说明不同胎次奶牛对性控冻精的应用效果具有明显的影响。     

母牛常用生殖激素的临床应用

近年随着产奶水平的不断提高,在一些高产奶牛群中,因生殖激素失调而引起的繁殖障碍亦有所增多。在临床治疗内分泌紊乱的不孕母牛过程中,由于缺乏对生殖激素的全面了解,而使用不当,不能取得预期效果,甚至出现一些不良反应。现将本场近年来母牛常用生殖激素的临床使用方法简介如下。1母牛常用的生殖激素种类1.1来自下丘脑的促性腺激素释放激素(GnRH)其主要功能为:促进和调节脑垂体前叶的分泌和释放促黄体素(LH)、促卵泡素(FSH)。临床用药以LRH-A3(促排Ⅲ)为多。1.2来自垂体前叶的促性腺激素主要有两种:一是促进卵泡发育和成熟的促卵泡素(…     

Successful Production of Offspring Using Cryopreserved Sperm via Nonsurgical Artificial Insemination in Rats

In rats, artificial insemination (AI) is surgically performed as a general tool to obtain offspring using cryopreserved spermatozoa. Nonsurgical AI is a more desirable technology because it does not require any surgical procedures. However, there has never been a successful nonsurgical AI since frozen-thawed rat spermatozoa show low motility. We show here for the first time successful nonsurgical AI in rats using oxytocin treatment. Intraperitoneal injection of oxytocin (1/800 IU) immediately before nonsurgical AI significantly increased the number of sperm collected from the oviducts compared with that without oxytocin treatment. Therefore, to obtain pups, oxytocin was intraperitoneally injected into females mated with vasectomized males, and the rats were then used for nonsurgical AI. Seven of the 12 oxytocin-treated rats became pregnant after nonsurgical AI, and 37 pups were obtained. Only one rat (1/13) without oxytocin treatment was pregnant after nonsurgical AI, and only 1 pup was delivered. These results show success for the first time in obtaining offspring using frozen-thawed rat spermatozoa via nonsurgical AI. Our results also suggest the possibility that oxytocin treatment is effective for improvement of nonsurgical AI even in other species.     

Objective Sperm Motion Analysis to Assess Dairy Bull Fertility Using Computer‐Aided System – A Review

Motility is one of the most important characteristics associated with the fertilizing ability of spermatozoa and is an expression of their viability and structural integrity. Computer‐assisted semen analyser (CASA) provides precise and accurate information on different sperm motion characteristics. This article reviews various aspects of computer‐aided motility analysis of bull sperm like sample preparation, standardization of instrument settings, importance of various motility parameters evaluated by the system and its impact on basic functional studies of spermatozoa. It gives special emphasis to various aspects of bull sperm motion analysis especially sub‐populations of spermatozoa, hyper‐activation, motion characteristic in different genetic and age groups, etc. and their utility in predicting the fertility of dairy bulls. The need to fill the gap in research and the necessity of universal standardization of the equipment has been discussed.     

定时输精对奶牛第一情期受胎率的效果分析

[目的]探讨不同月份和精液类型对利用定时输精程序处理奶牛后第一情期受胎率的影响.[方法]选择93头产后60 d以上不发情和产后配1～3次仍未受胎的奶牛,不检查卵巢直接利用激素生源2+1进行同期发情处理.1～3月份处理41头奶牛,6～8月份处理52头;其中,利用性控精液配种58头,常规精液配种35头.[结果]表明:经定时...