Bacteriospermia among smallholder artificial insemination boars in the Philippines and potential associated factors

Objective:To determine the prevalence of bacteriospermia,the bacterial load,and the potential factors associated with bacterial contamination in boar semen collected by local smallholder artificial insemination operators.Methods:Fifteen individual raw semen samples were collected from locally available artificial insemination boars owned by different smallholder boar operators within the 5th district of Leyte,Philippines and were subjected to standard bacteriological culture and identification,including a survey of potentially associated factors.Prevalence and bacterial count were determined accordingly,while boar characteristics and collection practices were clustered following agglomerative hierarchical clustering technique.Results:One hundred percent contamination with a bacterial count of(2.01±0.38)×10^(3) CFU/mL was observed.At least 73.33%of the samples were positive for Bacillus spp.,while other identified isolates included Enterobacter spp.,Staphylococcus spp.,E.coli,Pseudomonas spp.,Citrobacter spp.,and Klebsiella spp.Conclusions:Despite the high prevalence of bacteriospermia,the bacterial count is low.Nevertheless,on-farm practices on boar health and management,semen collection,and sanitation as well as the enhancement of basic protocols to control contamination should be conscientiously considered in smallholder artificial insemination operation.

Artificial Insemination of Cherry Valley Ducks with Muscovy Ducks

[Objective] To explore artificial insemination technique for production of mule ducks. [Method] Female Cherry Valley ducks were artificially inseminated with semen collected from male Muscovy ducks by massage method and vagina-insemination method to investigate the effects of insemination dose, insemination interval, insemination time and diluents on fertilization rate. [ Result ] The average fertilization rate was only 39.58%, when the female Cherry Valley ducks naturally mated with the male Muscovy ducks. However, it was increased to 74.79% by artificial insemination. The fertilization rate was 75.24% after semen was diluted by PBS buffer, while it was 75.16% after semen was diluted by Lake＇s buffer; however, there was not significant difference between the fertilization rate of the diluted semen and that of fresh semen （74.10%）. After semen was respectively diluted by PBS buffer and Lake＇s buffer and then stored at 5 ℃ for 24 h, the fertilization rate was low, respectively 23.76% and 34133%. [ Conclusion] Artificial insemination technology can reduce insemination dose and increase fertilization rate in production of mule ducks.

Study on Key Technique of Artificial Insemination for Silkworm,Bombyx mori

[Objective] The aim of this study was to investigate the efficient technique of artificial insemination for silkworm. [Method] Sperms were extracted from bursa copulatrix of female moths mated for 30 min through extruding and centrifugal method, and then the semen was injected into other virgin moths with trypsinase. [ Result] A high-effective collection technology of spermatids from silkworm was established successfully, 50 μl semen could be collected by only one person in each hour. The survival rate of spermatids was over 80% in vito after collected from bursa copulatrix, while the obtained semen was quite pure and the average fertilization rate of silkworm was 76,5%. [ Conclusion] The establishment of high-effective semen extraction technique of silkworm provides the technical basis for studies on other related techniques for silkworm sperm.

Efficiency of Artificial Insemination in Giant Pandas at the Wolong Breeding Center

The goal of the giant panda ( Ailuropoda melanoleuca ) breeding program is to develop a self sustaining,genetically diverse population.Due to the common problems about sexual incompatibility and a limited number of captive born males that breed naturally,artificial insemination (AI) has become a critical genetic management tool.It is common practice,however,to combine natural mating and AI using semen from non breeding males.From 1998 to 2000 at the Wolong breeding facility,12 of 18 (66.7%) females produced 20 cubs following combined natural mating and AI.The objective of this study was to determine the efficiency of AI without natural breeding.In 1998 and 2000,seven females were anesthetized for transcervical AI on two consecutive days.Ejaculates from six males were collected by electroejaculation,diluted in an egg yolk diluent containing 0% or 4% glycerol and used either fresh or following cold storage at 4℃ (for 24 or 48 h) or cryopreservation using the pellet freezing method.Mean (±SEM) ejaculate traits in six male sperm donors were:ejaculate volume,3.3±0.5 ml;sperm concentration,1,429.8±235.4×10 6/ml;sperm motility,81.7±2.1%;progression (0～5,5=best),3.1±0.1;and normal sperm,79.3±9.2%.For AI (n = 14) in seven females,mean inseminate traits were:spermic volume inseminated,2.4±0.3 ml;sperm motility,73.5±2.9%;progression,2.5±0.1;and total motile sperm inseminated/AI,684.2±118.2×10 6.Four of seven (57.1%) females became pregnant and produced five cubs of which four survived.Mean gestation and litter size was 131.5±9.7 days and 1.3±0.3 cubs/litter,respectively.These results indicate that the efficiency of AI is sufficient for recovering valuable genes from non breeding individuals to enhance genetic diversity in the ex situ population of giant pandas.

Lazzaro Spallanzani: pioneer of artificial insemination, multidisciplinary research, and scientific dissemination

Lazzaro Spallanzani(1729-1799)was a father of modern biology,with peculiar traits such as a multidisciplinary approach and penchant for scientific dissemination.Spallanzani consistently contributed to modern reproductive medicine by implementing experimental methods for the first historically successful artificial insemination.Nevertheless,he participated in discoveries pertaining to blood circulation,digestion,and respiration.Widely known in Europe in the eighteenth century,his fame prolonged to the following century,not exclusively through scientific acknowledgments,but even in literature.Nowadays,the figure of Spallanzani experience a kind of neglect and it would appear essential to maintain his work in the light of the history of medicine.

Estrus Synchronization and Artificial Insemination with Fresh and Chilled Semen in Assaf Ewes

This paper aims to study the efficiency of two short-term progestagen (FGA vs. MAP) + eCG treatments in estrus synchronization and artificial insemination (AI) with fresh or chilled semen in Assaf ewes fertility rate. All ewes received a subcutaneous implant of exogenous melatonin 45 days before been treated with short-term progestagens + eCG. By June 1st, ewes were divided in two groups: half was treated with an intravaginal sponge impregnated with 20 mg of FGA and the other half with an intravaginal sponge impregnated with 60 mg of MAP. Progestagen treatments lasted for 6 days. At sponge withdraw, all ewes were injected with 750 IU of eCG. Ovarian activity was assessed by plasmatic progesterone levels before and after progestagens + eCG treatment. Semen was collected by electro ejaculation and extended with Andromed? or OviXcell?. AI was performed 55 hours after eCG administration with fresh or chilled semen. During AI several factors were assessed: vagina mucosa color and lubrication, external cervical Os type, cervical mucous viscosity, semen deposition place and seminal cervix outflow. Semen was deposited as deep as possible without distress or trauma cervix mucosa. All Assaf ewes presented cyclic activity before progestagen + eCG treatments (2nd fortnight of May). Short-term progestagen + eCG treatments were equally efficient (100.0%). About 76.5% of Assaf ewes were pregnant 41 days after AI. Fertility rate was influenced by external Os type, semen deposition place and seminal cervix outflow. However, this rate was not conditioned by vaginal color or lubrication, cervical mucus viscosity, semen preservation technic and semen extender.

Factors Influencing the Superovulation and Artificial Insemination of Sheep

[Objective] This study aimed to find out a method for low-cost and highly efficient sheep superovulation treatment and artificial insemination. [Method] The factors those probably influencing the results of conventional superovulation and insemination, such as combination of FSH hormone and sponge suppository, estrus interval, number of insemination, and ram individuals were analyzed. [Result] The combination of sponge suppository and FSH produced in Beijing exhibited the poorest effect to superovulation, significantly worse than that of other combinations （P0.01）. The FSH produced in Ningbo, combined with sponge suppository or CIDR produced better effect to superovulation. The superovulation effect was better when the interval from the last FSH injection to estrus was 12 h, significantly better than that when the interval was 36 h （P0.01）; and there was no difference in the superovulation results when the interval was 0, 12 and 24 h. The pregnancy rate of two artificial inseminations was significantly higher than that of only one insemination （P0.01）. Rams themselves had significant influence on fertilization results. [Conclusion] The combination of domestic FSH and domestic sponge suppository cost much less and dose not reduce the superovulation results. Better fertilization result can be obtained if the ewes are inseminated twice with the sperm those gave high pregnancy rate.

Transfer of disulfide bond formation modules via yeast artificial chromosomes promotes the expression of heterologous proteins in Kluyveromyces marxianus

Kluyveromyces marxianus is a food-safe yeast with great potential for producing heterologous proteins.Improving the yield in K.marxianus remains a challenge and incorporating large-scale functional modules poses a technical obstacle in engineering.To address these issues,linear and circular yeast artificial chromosomes of K.marxianus(KmYACs)were constructed and loaded with disulfide bond formation modules from Pichia pastoris or K.marxianus.These modules contained up to seven genes with a maximum size of 15 kb.KmYACs carried telomeres either from K.marxianus or Tetrahymena.KmYACs were transferred successfully into K.marxianus and stably propagated without affecting the normal growth of the host,regardless of the type of telomeres and configurations of KmYACs.KmYACs increased the overall expression levels of disulfide bond formation genes and significantly enhanced the yield of various heterologous proteins.In high-density fermentation,the use of KmYACs resulted in a glucoamylase yield of 16.8 g/l,the highest reported level to date in K.marxianus.Transcriptomic and metabolomic analysis of cells containing KmYACs suggested increased flavin adenine dinucleotide biosynthesis,enhanced flux entering the tricarboxylic acid cycle,and a preferred demand for lysine and arginine as features of cells overexpressing heterologous proteins.Consistently,supplementing lysine or arginine further improved the yield.Therefore,KmYAC provides a powerful platform for manipulating large modules with enormous potential for industrial applications and fundamental research.Transferring the disulfide bond formation module via YACs proves to be an efficient strategy for improving the yield of heterologous proteins,and this strategy may be applied to optimize other microbial cell factories.

Application of Artificial Insemination in Selective Breeding of Native Beef Cattle in Wenzhou

[Objective]The paper was to improve the quality and growth rate of native yellow cattle in Wenzhou.[Method]Three groups of cattle were subjected to artificial insemination using frozen semen from Wagyu bull.The groups consisted of 20 native yellow cattle,20 Angus catle,and 20 Luxi yellow cattle.The heifers were subsequently evaluated for body size and body weight,and underwent treatment with estrus synchronization,artificial insemination,and early pregnancy diagnosis.[Result]The mean body size and body weight of native yellow cattle were found to be significantly lower than those of Angus cattle and Luxi yellow cattle(P<0.05).The estrus synchronization rate and mating rate of native yellow cattle were both 100%,while the corresponding rates for Angus cattle and Luxi yellow cattle were 90%and 95%,respectively.The ultrasound examination conducted on the 32m day following the mating revealed a distinct image of gestation sac,which,when considered alongside the findings of the rectal examination,may be indicative of pregnancy.The conception rates were 75%,72%,and 74%for native yllow cattle,Angus cattle,and Luxi yellow cattle,respectively.[Conclusion]The reproductive performance of native beef cattle is relatively superior.

Study on Artificial Propagation and Embryonic Development of Poyang Lake Catfish

Poyang Lake catfish （Silurus asotus Linnaeus） is native to Poyang Lake Basin. Artificial propagation of Poyang Lake catfish was carried out by using artificial insemination. Under water temperature of 18-26 ℃, embryonic development of Poyang Lake catfish in impounded water was observed and recorded in detail. Embryonic development of Poyang Lake catfish encountered seven stages, and it last- ed for 47.08 h from the fertilized egg stage to the stripping stage. The hatching time of Silurus meridionalis Chen was shortest, followed by that of Poyang Lake catfish, and the hatching time of Pelteobagrus vachelli was longest.

Effect of Uterine Anomalies on Pregnancy Rates and Reproductive Outcomes in Women Undergoing Artificial Insemination by Husband

Objective: Congenital uterine anomalies are common; however, their effects on artificial insemination by husband(AIH) and the period during which AIH is converted to in vitro fertilization(IVF) are unclear. We examined the influence of uterine malformations on reproductive outcomes following AIH and the optimum number of AIH cycles before resorting to IVF-embryo transfer(IVF-ET).Methods: We retrospectively recruited 168 patients with uterine malformations(anomalous group) undergoing AIH between January 2011 and December 2016. Meanwhile, 168 patients with infertility but with normal uteri(normal group) were matched as controls according to age.Results: The clinical pregnancy rate was similar in both groups(12.4% vs. 12.3%, P=0.950); the cancellation(21.6% vs. 4.4%, P< 0.001),early pregnancy loss(35.7% vs. 11.4%, P = 0.032), and preterm birth rates(21.4% vs. 2.9%, P = 0.038) were higher in the anomalous group,resulting in lower term birth(32.1 % vs. 74.3%, P =0.001) and live birth rates(50.0% vs. 77.1 %, P = 0.034). After two AIH cycles, the clinical pregnancy rate was lower(3.6% vs. 23.1%, P = 0.037) among women with uterine anomalies than among those with normal uteri. There was no difference in the pregnancy rates(52.5% vs. 53.7%, P= 0.908) between the two groups of patients with unsuccessful AIH who then underwent IVF-ET.Conclusions: IVF-ET can be performed immediately after two unsuccessful AIH cycles in patients with uterine malformations. In patients undergoing AIH or IVF, uterine malformations increase the risk of adverse obstetric outcomes.

Effect of administration of phenylephrine immediately after low dose insemination on pregnancy rates in mares

There is considerable pressure on equine veterinarians to achieve good pregnancy rates with very small doses of semen. Phenylephrine administration in the rabbit increased numbers of oviductal, uterine, and cervical sperm, myometrial contractions, and fertilized ova after low dose insemination. The use of phenylephrine to enhance uterine contractility and fertility has not been investigated in the mare. Thus, the objective of this study was to determine if phenylephrine administration would result in clinically acceptable pregnancy rates in mares bred by low dose insemination. The hypothesis (Ha) was that pregnancy rates would be significantly higher in mares receiving phenylephrine compared to saline controls. Six pony mares and eight horse mares were enrolled in this study. Mares were inseminated within 24 hours of ovulation with 30 million progressively motile spermatozoa from a single fertile stallion. Immediately following insemination, mares were administered either phenylephrine (0.06 mg/kg) or 1mL of saline via IV injection. Pregnancy status was determined 14 days following ovulation via transrectal ultrasonography. Pregnancy rates in phenylephrine treated mares were 44% (4/9) while 22% (2/9) in saline-treated mares (P > 0.05).

The Impact of Seasonal Variation on Clinical Pregnancy and Live Birth Rates in Assisted Reproductive Technology: A Retrospective Cohort Study in Hainan

Objective:To investigate the influence of season on live birth and clinical pregnancy rates,as well as assisted reproductive technology(ART)outcomes,in the Hainan region.Methods:Patients were categorized into four groups based on the dates of artificial insemination and transplantation:spring,summer,autumn,or winter.The main outcome measures were clinical pregnancy rates and live birth rates.Secondary outcomes included body mass index(BMI),oocyte number,two pronuclei(2PN)cleavage rate,total gonadotropin(Gn)dosage and days,age,2PN fertilization rate,sperm concentration,sperm PR rate,anti-Müllerian hormone(AMH),and endometrial thickness.Outpatient semen quality indicators included sperm PR rate,total sperm count,sperm concentration,and total sperm motility.Results:This retrospective cohort study analyzed 2,016 artificial insemination cycles and 1,783 ovarian retrieval cycles from January 2017 to October 2022,and assessed the semen quality of 6,651 outpatients from May 2017 to October 2022.In artificial insemination cycles,sperm PR rate and clinical pregnancy rate were highest in winter,with a statistically significant difference between groups(P<0.05).Clinical pregnancy rate was influenced by both age and sperm PR rate(P<0.05).In ovarian retrieval cycles,the winter group had significantly higher clinical pregnancy,2PN fertilization,and 2PN cleavage rates than the other groups.The autumn group had higher live birth rates,though not significantly different.Additionally,winter months showed higher total sperm concentration and total sperm number compared to other seasons.Conclusion:Seasonality affected clinical pregnancy and live birth rates in artificial insemination cycles but not in ovarian retrieval cycles in the Hainan region.These findings suggest that while there is no need to choose a specific season for ovarian retrieval cycles,artificial insemination in winter may be preferable for patients.

基于子宫内膜结构与子宫螺旋动脉血流参数构建人工授精妊娠预测模型及验证

背景:现子宫内膜结构及子宫螺旋动脉血流参数对夫精宫腔内人工授精(artificial insemination by husband,AIH)妊娠率的影响水平尚不明确,该研究通过校准其他混杂因素后,确定了其独立影响因素,并构建了预测模型,具有较好的临床应用效能。目的:基于子宫内膜结构及子宫螺旋动脉血流参数构建AIH临床妊娠预测模型及验证。方法:回顾性分析2017年1月至2021年1月于常州市妇幼保健院接受AIH助孕治疗患者共1299例,将其中1182例未临床妊娠者纳入未妊娠组,117例临床妊娠者纳入妊娠组;通过1∶1倾向评分匹配,妊娠组与未妊娠组各匹配成功93例;采用单、多因素分析筛选子宫内膜结构及子宫螺旋动脉血流参数对AIH结局的影响因素,通过受试者工作曲线确定各独立影响因素的最佳截断值,限制性立方样条法分析各独立影响因素对AIH妊娠影响的风险趋势,临床决策曲线与临床影响曲线对该联合预测模型的临床应用效能进行检验。结果与结论:①倾向评分后妊娠组与未妊娠组各非内膜因素均无显著统计学意义,数据具有较好的均衡性(P>0.05);②单因素分析结果显示,内膜下血管化指数、血流指数、血管化血流指数、子宫动脉阻力指数、子宫动脉搏动指数、收缩期最高血流速度/舒张期末血流速度、基底子宫内膜到外子宫肌层内层平均交界区、最大交界区厚度为AIH妊娠的影响因素(P<0.05);③多因素Logistic回归结果显示,基底子宫内膜到外子宫肌层内层平均交界区厚度、子宫动脉搏动指数、血管化血流指数为AIH妊娠的独立影响因素,影响大小依次为血管化血流指数>基底子宫内膜到外子宫肌层内层平均交界区厚度>子宫动脉搏动指数;④受试者工作曲线显示,血管化血流指数的曲线下面积为0.704(0.629,0.779),最佳截断值为6.26;基底子宫内膜到外子宫肌层内层平均交界区厚度的曲线下面积为0.660(0.582,0.739),最佳截断值为6.38;子宫动脉搏动指数的曲线下面积为0.642(0.563,0.721),最佳截断值为1.18;⑤限制性立方样条曲线显示,当血管化血流指数>6.24时,其对AIH妊娠具有显著的正影响趋势;基底子宫内膜到外子宫肌层内层平均交界区厚度≤6.55 mm时,其对AIH妊娠具有显著的正影响趋势;当子宫动脉搏动指数>1.27时,其对AIH妊娠具有负影响风险;⑥临床决策曲线与临床影响曲线显示,该联合预测模型在阈概率值为0.17-0.93时具有临床最大净获益,且在该阈概率范围内损失与获益的比值始终小于1,显示出该联合预测模型具有较好的临床效能;⑦结果表明,通过倾向评分与多因素Logistic回归校正子宫内膜外其他混杂因素后,基底子宫内膜到外子宫肌层内层平均交界区厚度、子宫动脉搏动指数、血管化血流指数为AIH妊娠的独立影响因素,通过对其最佳截断值的确定与风险趋势性评估,证实该联合预测模型具有较好的预测价值与临床应用效能。

鸡精液甘油简易冷冻保存技术改进与优化效果评价

[目的]改进与优化鸡精液甘油细管简易冷冻保存技术。[方法]采用单因素设计试验,使用6%的冻存(3、6、9个月)与现配甘油保护液制作细管冷冻精液,比较冷冻精液冻后精子活力、活率及畸形率。采用液氮面上熏蒸法优化一步冷冻法冷冻速率,并用优化后一步冷冻法与前期研发的两步冷冻法制作细管冷冻精液,检测两种冷冻方案冻后与离心去甘油后的精子活力、活率、畸形率及种蛋受精率、孵化率。采用一步冷冻法冷冻不同品种公鸡精液,并采用不同输精轮次应用于不同年龄母鸡,通过输精试验评价输精效果。[结果]①添加冻存3、6、9个月的甘油保护液与现配甘油保护液冻后精子活力、活率、畸形率均无显著差异(P>0.05)。②经优化和重复率比较后一步冷冻法最佳冷冻速率为细管精液距离液氮面3 cm冷冻3 min,样品精子活力≥60%的重复率为100%,精子活力≥65%的重复率为65%。③一步冷冻法精子活力、精子活率分别为62.84%和76.00%,均极显著高于两步冷冻法(58.17%和68.62%)(P<0.01),两种冷冻方案的精子畸形率无显著差异(P>0.05)。一步法、两步法冷冻精液离心去甘油前、后平均精子活力、种蛋平均受精率和平均孵化率均无显著差异(P>0.05),单日最高受精率分别为68.34%和80.00%。④采用一步冷冻法制备的黑凤鸡与湘东鸡冻精输精后的种蛋受精率和孵化率均无显著差异(P>0.05)。给30周龄母鸡输精后种蛋受精率极显著高于68周龄母鸡(P<0.01)。3轮4次输精模式种蛋受精率极显著高于1轮2次输精模式(P<0.01)。[结论]将甘油保护液制备成储备液在―20℃冻存,采用一步冷冻法并预先进行冷冻速率优化,输精时注意精液冷藏时长、母鸡年龄、输精轮次,能得到稳定较好的输精效果。

Applying bases for "double control" artificial breeding of giant panda in captivity

THE giant panda is a kind of endangered rare animal,the number of which is less than onethousand at present,specially distributed in China.According to the protective scheme issuedby The International Association of Nature Protection,stock population in captivity must

人工授精女性痛苦表露状况及影响因素分析

目的:了解人工授精女性痛苦表露状况并分析其影响因素。方法:选择2021年4月-2023年4月本院收治的人工授精不孕症女性患者148例,使用一般资料调查问卷、痛苦表露指数量表(DDI)、领悟社会支持量表(PSSS)、Locke-Wallace婚姻调试量表(MAT)进行调查,以Pearson相关系数模型分析PSSS评分、MAT评分与人工授精女性痛苦表露水平的关系,并以元线性回归模型分析人工授精女性痛苦表露影响因素。结果:本次共发放问卷148份,有效回收138份,有效率为93.2%。138例女性DDI评分35.25±5.48分,低水平占比14.5%、中等水平占比73.2%、高水平占比12.3%;PSSS评分53.15±9.67分,MAT评分99.56±12.21分。单因素分析显示,不同年龄、家庭人均月收入、居住地、是否为夫精人工授精、人工授精次数的人工授精女性痛苦表露评分存在差异,Pearson相关分析PSSS、MAT评分与人工授精女性DDI评分呈正相关(均P<0.001);多元线性回归分析,家庭人均月收入、是否为夫精人工授精、PSSS评分、MAT评分对人工授精女性痛苦表露水平有正向影响,人工授精次数对人工授精女性痛苦表露水平有负向影响(均P<0.05)。结论:本次调查的人工授精女性痛苦表露处于中等水平,家庭人均月收入、是否为夫精人工授精、人工授精次数、社会支持、婚姻亲密关系等是其重要影响因素,临床应高度重视并给予针对性护理干预,以提升人工授精女性痛苦表露水平,促进身心健康。

B超监测梅花鹿性控精液腹腔镜输精试验

梅花鹿常规冻精与性控冻精解冻后进行品质鉴定,结合B超监测卵泡有选择的对60只同期发情处理的梅花鹿进行腹腔镜精准输精。数据分析显示,同期发情处理后梅花鹿卵巢B超监测结果与腹腔镜输精受胎率存在明显的正相关;X和Y型冻精产仔率为83.33%,而常规冻精产仔率为65.31%,X、Y型冻精与常规冻精组间差异显著(P<0.05);常规冻精组、X冻精组与Y冻精组所产后代性别比(公/母)分别为9:8、0:10和16:1,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)。结果表明,结合B超监测有选择的进行梅花鹿性控精液腹腔镜人工输精,可显著提高受胎率,降低成本,技术可行。

影响驴人工授精情期受胎率的因素分析

为了提高母驴情期人工授精受胎率,试验选取新疆喀什地区的母驴为试验对象,对母驴不同生理状态、产驹天数、配种季节、配种次数、最后一次配种距离排卵的间隔时间、不同授精剂量和不同稀释液等7个方面因素开展了相关研究。结果表明:人工授精2次、3次、4次和5次的情期受胎率显著高于1次(P<0.05),排卵前24 h和48 h人工授精的情期受胎率极显著高于排卵后0~24 h内授精(P<0.01),精液稀释后用注射器向子宫授精(原精)5~10 mL,情期受胎率极显著高于浓缩精液子宫角细管授精(原精)2 mL(P<0.01)。说明驴一个情期人工授精2~5次、最后一次配种距离排卵间隔时间为24~48 h可获得较高的情期受胎率,增加输精剂量可以提高母驴情期受胎率。

雉鸡人工授精及注意事项

雉鸡是一种驯化时间较短的珍禽,在国内真正开展规模化人工养殖也仅30余年时间。初期由于受雉鸡特有生理特性和生产特点影响,主要采用小群地面平养和自然交配的传统饲养模式,生产水平低下。进入21世纪后,国内部分雉鸡种源企业经过10余年的技术创新,在攻克雉鸡单鸡单笼多层立体笼养的基础上,探索形成了雉鸡人工授精实用操作技术。该技术结合雉鸡特有生理特性和生产特点,从种雉准备与调教、采精与精液处理、输精时间与方法等方面,规定了相关操作要领和注意事项,显著提升了种雉人工饲养的生产水平。