Prostaglandin F2α Treatment Associated with Timed Artificial Insemination in Ewes

Traditional treatments of two prostaglandin F2 alpha (PGF2alpha) doses at 10-day intervals or more did not result in acceptable pregnancy rates in timed artificial insemination (TAI) programmes in ewes. An explanation might be the undefined time-period of the onset of oestrus and ovulation after the treatment. Recently a consistent interval to oestrus and ovulation was obtained by giving PGF2alpha at day 3 post-ovulation, i.e. when the largest follicle of the first follicular wave of the cycle was still growing. This can be achieved when a second dose of PGF2alpha is given 7 days after a first dose. In this work, we evaluated the synchronization of oestrus and determined which of three different moments of TAI was the most successful using a PGF2alpha (PG-7d) protocol in a large flock. A total of 436 nulliparous and multiparous ewes were treated with two doses of a PGF2alpha analogue (delprostenate 160 microg, i.m.) separated by 7 days. Onset of oestrus was recorded twice a day and a single cervical TAI with fresh undiluted semen was performed either at 42 h (n = 152), 48 h (n = 120), or 54 h (n = 164), after the second PGF2alpha dose without taking into account the oestrous response. Pregnancy rate was determined by transrectal ultrasonography 30 days after insemination. Onset of oestrus was detected in 308 of 328 and 89 of 108 multiparous and nulliparous ewes, respectively (p < 0.001), within 72 h after treatment. The distribution of the onset of oestrus did not differ between multiparous and nulliparous ewes and the highest proportion of ewes in oestrus was detected between 25 to 48 h (313/397) from the second PGF2alpha dose. The pregnancy rate in ewes inseminated at 42 h tended to be higher than those inseminated at 48 h (p = 0.09) and was higher than those inseminated at 54 h (p < 0.05) (56/152, 31/120, 37/164; respectively). Therefore, the use of the PG-7d protocol resulted in a very high synchronization of oestrus with the highest concentration (around 80%) between 25 to 48 h from the end of treatment. The best pregnancy rate (37%) was obtained after a single cervical TAI with fresh semen at 42 h.     

不同稀释液和输精量对天柱黑番鸭人工授精效果的影响

天柱黑番鸭是我国4个地方番鸭品种之一,已被列为地方品种资源进行保护和利用.由于骡鸭属于属间杂交的产物,自然交配受精率很低,仅为15%～45%,因此,开展人工授精是提高番鸭受精率根本途径.     

Distribution of Live and Dead Spermatozoa in the Genital Tract of Gilts at Different Times After Insemination

Twenty-four gilts were inseminated pair-wise with live or dead spermatozoa from the same ejaculate. The insemination dose was 100 ml undiluted semen containing, on average, 19×10⁹ spermatozoa. The gilts were slaughtered 1, 2, 6 and 12 h after insemination. The numbers of spermatozoa were counted in the uterus, uterotubal junction and in four equally long segments of the oviduct, called I–IV, with a haemocytometer. IV was adjacent to the uterotubal junction. The numbers of spermatozoa recovered in the uterus diminished significantly during the first 12 h after insemination. From gilts inseminated with live spermatozoa more spermatozoa were recovered in the uterotubal junction than from gilts inseminated with dead spermatozoa. Two h after insemination spermatozoa were recovered in all oviducts. Significantly more live than dead spermatozoa were recovered in Segments III and IV of the oviduct, regardless of time. In gilts inseminated with live spermatozoa the sperm count in Segment I varied significantly with time, being hiigest 2 h after insemination. At 6 and 12 h there were no distinct differences in the distribution of live spermatozoa between the various oviduct segments. The numbers of spermatozoa recovered in the oviduct were at these times apparently related to the sperm depots in the uterotubal junction.     

Artificial Insemination with Frozen Semen in Ewes at Different Times of the Breeding Season

Totally 13575 ewes of two different breeds, Dala and Spel, were inseminated with semen, frozen in straws and thawed at 70°C for 8 sec. An insemination dose of 0.2 ml containing approx. 150 × 10⁶ spermatozoa with at least 45 to 50% progressive motility was imerted 5 to 12 mm into the cervix. The insemination was performed once between 12 and 30 h after the onset of heat. The NR rate of the Dala ewes increased significantly during the season. The NR rate of the ewes inseminated before 15. November was 44.3%, from 15. to 20. November 52.2%. from 20. to 25. November 55.3% and from 25. November and later 61.4%. The corresponding values for the ewes of the Spel breed were 57.3, 58.7, 61.5 and 71.0% respectively, and only the difference between the two last values was statistically significant. The difference between the fertility of the two breeds was significant within each of the periods .     

Use of Porcine Luteinizing Hormone at Oestrous Onset in a Protocol for Fixed‐Time Artificial Insemination in Gilts

The aim of this study was to evaluate the effect of porcine luteinizing hormone (pLH) given at oestrous onset in gilts, by different routes and doses, on the interval between onset of oestrus and ovulation (IOEO) and reproductive performance using a single fixed‐time artificial insemination (FTAI). A total of 153 gilts were submitted to oestrous detection at 8‐h intervals and assigned to three groups: control – without hormone application and inseminated at 0, 24 and 48 h after oestrous onset; VS2.5FTAI – 2.5 mg pLH by the vulvar submucosal route at oestrous onset and a single FTAI 16 h later; IM5FTAI – 5 mg pLH by the intramuscular route at oestrous onset and a single FTAI 16 h later. More VS2.5FTAI gilts (47.1%; p < 0.05) ovulated within 24 h after oestrous onset than control gilts (25.5%) whereas IM5FTAI gilts had an intermediate percentage (31.4%; p > 0.05). The IOEO tended to be shorter (p = 0.06) in VS2.5FTAI (30.2 ± 1.4 h) than in control (34.7 ± 1.4 h) gilts, but there was no difference (p > 0.05) between control and IM5FTAI (32.8 ± 1.4 h) gilts. Farrowing rate was not different (p > 0.05) among treatments. Total born piglets (TB) was lower (p < 0.05) in VS2.5FTAI (12.3 ± 0.4) than in control gilts (14.1 ± 0.4), whereas intermediate TB was observed in IM5FTAI gilts (13.3 ± 0.4). Due to the advancement of ovulation, reduction of the hormonal dose and the ease of application, the vulvar submucosal route would be the best option for FTAI protocols, but their negative impact on litter size remains to be elucidated. Taking into account the good fertility results obtained in IM5FTAI gilts whose ovulation was not advanced, the possibility of a single FTAI without any hormonal treatment should be further investigated, to establish reliable FTAI protocols for gilts.     

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。     

鸵鸟输精方法初探

采用手臂引导法给５只鸵鸟进行阴道内输精,共输精１６次,并在２周内收蛋１７枚,其中有受精蛋８枚,受精率为５０%,经孵化获得雏鸟７只。试验初步认为,对母鸵鸟进行训练后,用此方法进行输精是可行的;对鸵鸟这样大型的鸟类,进行阴道浅部输精效果较好。     

荷斯坦奶牛性控冻精人工授精应用效果的研究进展

近年来,对性别控制的研究呈现出迅速发展的趋势。应用性控冻精进行人工授精,是快速增加优质高产奶牛数量的有效途径。奶牛性控冻精的人工授精技术是将奶牛种公牛的精液通过精子分离仪使含X、Y染色体精子得到有效地分离,再将分离后得到的X精子冷冻制成冻精,进行人工授精,从而使母牛怀孕产母犊的技术。     

不同同期发情及定时输精技术对新疆细毛羊受胎率的影响

新疆细毛羊为季节性发情动物,大多数细毛羊每年产1胎,多为1胎单羔。因此,受胎率是决定养羊经济效益的关键因素之一。定时输精技术可以有效地提高母畜的利用率和受胎率,已成为养羊生产中的一项重要技术。为了提高绵羊的繁殖效率,本试验采取3种不同方法分别对青年母羊进行同期发情处理,比较研究了发情后不同定时输精技术及输精时间对受胎率的影响。结果表明,3种同期发情的处理方法均取得了较高的同期发情率,其中CIDR栓+PGF2α方法的同期发情效果较好;青年母羊最佳定时输精技术是腹腔镜输精技术;最佳输精时间为发情后的48 h。     

同期发情在肉牛人工授精领域的研究与应用

阐述了国外肉牛同期发情技术的研究与应用进展,结合我国南方肉牛产业的养殖现状,分析了制约该技术推广应用的几个关键问题,并从技术上提出了解决相关问题的几点思考.     

The Influence of Insemination Conditions on Embryonic Diversity in Gilts Depends on Their Social Condition

Contents A 22 factorial design (factors: sociel environment during rearing and insemination conditions) was applied to gilts. Social conditions differed from an age of approximately 137 days onwards, 30 gilts being individually housed (group 1) and 36 gilts being pairwise housed plus having daily boar contact from approximately 180 days of age onwards (group 2). Insemination conditions of gilts at third oestrus consisted of either only artificial insernination or artificial insemination immediately followed by mating with a vasectomized boar. Gilts were slaughtered at Day 9,10 or 11 after insemination. Experimental treatments did not affect average diameter, surface area, volume, DNA- or protein content of litters. Within-litter embryonic diversity (s.d.) increased with average embryonic development in terms of diameter in all four experimental treatments. The rate of increase, however, differed significantly between experimental treatment (P < 0.05). Mating by a vasectomized boar resulted in a greater rate of increase in within-litter diversity in individually housed gilts, but a reduced rate of increase in diversity in the pairwise housed gilts. The possible consequences of this effect regarding embryonic mortality after Day 11 of pregnancy are discussed. Although based on a relatively small number of litters (49 in total), in the present study, within-litter embryonic diversity was significantly affected by an interaction between insemination conditions and social environment of the gilts. Further research will be needed to extend the data on this relation and focus on the causal analyses of the observed phenomena. Inhalt: Einfluß von Besamungsbedingungen und sozialem Umfeld auf die embryonale Variabilität von Schweineembryonen Ein 22 faktorieller Versuchsaufbau (Faktoren: soziales Umfeld während der Ayfzucht und Besamungsbedingungen) wurde bei Sauen geprüft. Das soziale Umfeld war ab Tag 137 unterschiedlich; 30 Sauen wurden in Einzelhaltung (Gruppe 1) und 36 Sauen wurden paarweis gehalten (Gruppe 2). Ab Tag 180 hatte Gruppe 2 täglich Kontakt mit einem Eber. Sauen im dritten Östrus wurden entweder nur künstlich besamt oder wurden unmittelbar nach der künstlichen Besamung zusätzlich von einem vasektomierten Eber gedeckt. Die Sauen wurden an Tag 9,10 oder 11 nach der Besamung geschlachtet. Innerhalb der Würfe nahm die embryonale Variabilität (s.d.) bezäglich des durchschnittlichen embryonalen Entwicklung (Durchschnitt des Embryos) in allen vier Versuchsgruppen zu. Die Zunahme der embryonalen Variabilität (s.d.) unterschied sich signifikant zwischen den Versuchsgruppen (P < 0.05). Die Deckung mit einem vasektomierten Eber resultierte in einer größeren Zunahme der embryonalen Variabilität innerhalb des Wurfes bei Sauen in Einzelhaltung, jedoch zeigte sich eine verminderte Zunahme der embryonalen Variabilität bei paarweise gehaltenen Sauen. Mögliche Konsequenzen dieses Effektes im Hinblick auf die embryonale Sterblichkeit nach 11-tägiger Trächtigkeit werden diskutiert. Obwohl in der vorliegenden Studie relativ wenige Würfe (49 insgesamt) berücksichtigt wurden war die Variabilität innerhalb der Würfe signifikant beeinflußt durch eine Interaktion zwischen Besamungsbedingungen und sozialem Umfeld der Sauen. Weitere Versuche werden nötig sein, um diese Beziehungen zu sichern und sich mit den Ursachen der beobachteten Phänomene zu befassen.     

狮头鹅人工授精技术参数测定

<正>应用鹅的人工授精技术,能克服对水源等生态环境的依赖性,克服不同品种、公母体重悬殊、择偶性等造成的交配困难,减少公鹅的饲养量,提高种蛋受精率,具有相对于自然交配的优越性。在生产中应用该项技术能节省成本,提高生产水平;在育种中应用该项技术,能加速育种进程,促进地方鹅种的品种改良[1]。     

蜂王人工授精技术概要

蜂王人工授精技术是蜜蜂育种的重要手段。本文从雄蜂及处女王的培育到环境设施消毒、雄蜂捕捉、精液采集、授精及授精后蜂群管理等各环节概要介绍了蜂王人工授精技术的操作要点．为蜂王人工授精技术的实施起到一定的指导作用。     

笼养肉种鸡人工授精的手法

笼养鸡的人工授精技术含量高,要求管理人员不仅要精通此项技术,而且要严格的要求饲养人员遵守操作程序,规范技术和手法,以求获得稳定的生产成绩.现针对笼养肉种鸡介绍人工授精的手法及相关要点.     

Supplementation with Whole Sunflower Seeds Before Artificial Insemination in Beef Heifers

The objective of this study was to evaluate synchronization and pregnancy rates of beef heifers supplemented with 0.91 kg of whole sunflower seeds for 0, 30, or 60 d before AI. Beef heifers from four locations (n = 1,014) were assigned by BW to treatment (within location) and randomly to AI sire. Heifers at Location 1 (n = 176; mean BW = 332 kg) received either 0- or 60-d sunflower seed treatments. Heifers at Location 2 (n = 397; mean BW = 334 kg) were fed sunflower seeds for 0, 30, or 60 d. Heifers at Locations 3 (n = 211; mean BW = 345 kg) and 4 (n = 230; mean BW = 343 kg) received 0- or 30-d sunflower seed treatments. Within location, diets were formulated to be isocaloric and isonitrogenous. All heifers received melengesterol acetate (0.5 mg/d per head) for 14 d followed 19 d later by an injection of prostaglandin F_2a (PGF) (25 mg). Heifers were bred by AI according to the AM/PM rule except on d 3 when all heifers that had not exhibited estrus were artificially inseminated in mass. Neither 72-h estrous response nor pregnancy rate was affected (P>0.10) by 30- or 60-d sunflower feeding. In summary, feeding 0.91 kg of whole sunflower seeds for either 30 or 60 d before AI did not improve estrous response or pregnancy rate when compared with controls.     

OvSynch法处理进行黄牛定时人工授精研究

利用国产GnRH、PGF2α和EB等外源激素对本地黄牛进行处理，观察了OvSynch处理进行定时人工授精的繁殖效果，并探讨了卵巢状况对GnRH作用是否存在影响。结果显示：（1）各试验组同期发情率与对照组差异不显著（P＞0．05），但发情同期化程度显著高于对照组，且能够集中定时进行人工授精；（2）试验Ⅰ、Ⅱ组的第一情期受胎率分别为60．0％、58．3％，与对照组（42．9％）之间无显著差异（P＞0．05）；（3）GnRH类似物能够调控卵泡发育波，其作用不受卵巢状况的影响。试验表明，采用国产GnRH对本地黄牛进行OvSynch处理，能够达到定时人工授精且不降低受胎率的目的。     

欧拉型藏羊的人工采精与细管冷冻精液授配技术研究

为提高青海省本地优质藏羊选育工作,笔者对青海省果洛州玛多县6只欧拉型藏公羊和20只欧拉型藏母羊进行优质选育试验,结果表明:藏公羊鲜精采集量平均为1.5mL,呈乳白或乳黄色、无气味、有云雾状,冻前鲜精活力平均为0.65,平均活力高出国家羊精子标准活力的0.075,冻后活力为0.3到0.5,平均活力高出国家羊精子标准活力0.1。且经冷配后的20只藏母羊均无返情现象。本试验对于藏羊的改良有重要的实践意义,对于改善纯藏羊品种也有重要的参考指导意义。     

羊人工授精三级网点的建立

由精液供应站，精液转运站和输精点组成的羊人工授精三级网点，能更充分地利用优良种公羊精液，扩大配种范围，加速羊群改良。本文对三级站点的任务要求及应配备的设施和人员作出具体的论述。