引进良种肉牛冻胚规模移植技术研究

从加拿大引进良种肉牛利木赞、西门塔尔、盖洛威冻胚,移植受体489头次.得到以下研究结果120d直检妊娠249头(50.9%),产犊221头,产程死亡13头,产犊成活率94.1%.应用氯前列烯醇同期发情,累计处理受体牛930头次,880头次出现发情(94.6%),847头次达到同期发情,72h内同期率为91.1%.经产黄牛移植成功率49.2%(211/429);育成荷斯坦牛移植成功率63.3%(38/60).首批选中的受体移植成功率为60.1%(158/263);首批移植落选牛和移植后未孕牛再进行选择,移植成功率36.4%(64/176);而对类似情况的受体牛经医疗护理和加强饲养管理,两个月后再进行第三批移植,成功率为54.0%(27/50).A级黄体受体牛移植成功率54.7%(41/75);B级黄体受体牛移植成功率44.7%(115/257),统计差异不显著(P＞0.05).桑椹胚(155枚)在周期的第6d、6.5d和7d的移植成功率分别为55.0%(33/60)、51.5%(34/66)和51.7%(15/29),统计分析6d与6.5d、7d差异不显著(P＜0.05);而囊胚(158枚)在周期的6d、6.5d和7d的移植成功率分别为47.2%(25/53)、54.8%(17/31)和75.7%(56/74),6.5d与7d差异显著(P＜0.05),6d与7d差异极显著(P＜0.01).犊牛品种和性别对初生重有一定影响.犊牛总平均妊娠期为288.78±4.89d.     

谈谈杂交水稻制种父母本的花期预测与调节

根据父母本开花习性的观察，提出了父母本最佳花遇标准，分析了父母本花期不遇产生的时期和造成花期不遇的原因，指出幼穗分化前是父母本花期预测和调节的最佳时期，幼穗分化后的调节仍是有效的。     

东北细毛羊发情和排卵规律的研究

本实验系统观察了东北细毛羊的繁殖季节开始时间、发情周期长度、发情持续时间、排卵时间及早期胚胎发育进程等。结果表明：（１）在黑龙江地区大多数（７０．３％）东北细毛羊于７月２１日至８月９日开始发情季节，也即于夏至后１个月至５０ｄ内开始发情；（２）发情周期平均长度１６．６３±０．８４ｄ，８０％的羊为１６～１７ｄ，方差组分估计和Ｆ检验判断，发情周期长度在羊个体间和个体内的差异均不显著；（３）平均发情持续时间３８．３４±１３．７３ｈ，８５％的羊为２４～４８ｈ，方差组分估计和Ｆ检验证明，发情持续时间的个体差异显著且个体间差异显著大于个体内差异；（４）发情开始后２６～３５ｈ排卵；（５）发情５１ｈ胚胎处２．细胞期，６６～７２ｈ处４～６细胞期，７６～８１ｈ处８－细胞期。     

利用GnRH、PGF2α和PRID进行黄牛程序化人工授精

在一个处于自然散养状态下的本地黄牛群体中 ,比较了发情 /排卵同期化并定时人工授精组和仅同期发情处理后适时人工授精组黄牛的繁殖效果。 5 3头健康无病的本地黄牛随机分为 4组 ,试验 组 (Ov Synch法 ) ,注射 Gn RH-PGF2α- Gn RH;试验 组 ,注射 Gn RH- PGF2α- EB;试验 组 ,放置 PRID- PGF2α- EB;对照组 ,注射 PGF2α- PGF2α。其中 ,试验 、 、 组分别在处理结束后 16～ 2 0、2 4、2 4 h进行定时人工授精 ,对照组在鉴定发情后作适时输精。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 .0 5 ) ,;(2 )试验 、 、 组所有授精牛均分别集中在处理结束后16～ 2 3、2 4～ 2 8、2 4～ 2 8h内完成人工授精 ,而对照组处理牛接受人工授精时间非常分散 ;(3)试验 、 、 组的第一情期受胎率分别为 6 0 .0 %、5 8.3%和 5 7.1% ,与对照组 (42 .9% )之间无显著差异 (P>0 .0 5 )。结果表明 ,试验组 3种程序处理黄牛均可以达到定时人工授精且不降低受胎率的目的。尤其是 Gn RH- PGF2α- EB程序 ,成本低、处理效果好 ,适宜在生产中推广应用     

青海毛肉兼用半细毛羊同期发情及提高受胎率的试验（二）

采用不同生殖激素在９７３只青海志肉兼用半细毛羊中进行同期发情和提高受胎率试验。结果表明：①５ｄ和１０ｄ内的同期发情率,总受胎率在Ｐ４＋ＰＭＳＧ组分别为７６．３２％,９７．３６％和９４．７４％;Ｐ４＋ＩＣＩ８０９９６组为９０．０％,１００％和１００％;ＰＭＳＧ组为６３．１６％,９５．７９％和９４．７４％;ＩＣＩ８０９９６组为８２．９１％,９５．５８％和９４．９３％,同期发情效果均显著或极显著高于对照     

Conception rates in farm mink (Neovison vison) in relation to first mating date,age and color variety

The aim of the study was to analyze the effects of the first mating date, age and color variety on the conception rates in farm mink. We analyzed female mink reproductive performance in 492 Sapphire and 463 Standard Black females over 3 or 4 years. The analysis included the number of inefficient matings, the interval between the first inefficient mating and the efficient mating (copulation) and the conception rates. The results show a significant effect of female's age and color variety on the conception rates. The youngest, yearling females of either color needed a higher number of matings per conception, as compared to older, 2‐ and 3‐year‐old females. Black females demonstrated a higher number of inefficient matings (1.066), as compared with Sapphires (0.730). Yearling females were most often mated from 1 to 10 March, and older females from 11 to 20 March. Older females achieved better conception rates than the yearlings. Dates between 11 and 25 March proved to be the optimum for the first mating, since the highest conception rates were observed if the females had mated during this period.     

Effect of synchronization protocols on reproductive indices,progesterone profile and fertility under subtropical environmental conditions in repeat breeder Holstein cows

The objectives were to evaluate the reproductive indices and survival analysis of pregnancy outcomes in multiparous repeat breeder Holstein cows (n = 557). The cows were synchronized to ovulate by Ovsynch, new controlled internal drug release device (N‐CIDRsynch), and once‐used CIDR device (U‐CIDRsynch). The pregnancy per AI at 28 days post‐insemination (P/AI 28) in the N‐CIDRsynch group (28.75%) was significantly (COR = 1.49; p = 0.011) greater than that reported in the Ovsynch (23.46%) and U‐CIDRsynch (21.73%) groups. Furthermore, the pregnancy per AI at day 75 post‐insemination (P/AI 75) in the N‐CIDRsynch group was significantly greater than the Ovysync group (COR = 1.35; p = 0.050). The repeat breeder cows received a N‐CIDR device had a significantly higher progesterone level on day 2 and day 4 of CIDR insertion (1.38 and 1.67 ng/ml, respectively) than those received a U‐CIDR device or the control group (p = 0.012 and 0.001, respectively). The Cox regression model recorded significant associations for synchronization protocols, THI at the TAI and season of calving with the hazard of P/AI 28 and P/AI 75 (p = 0.044 and 0.046; 0.001 and 0.005; 0.003 and 0.001, respectively). Multiparous repeat breeder cows (>3) had a lower hazard ratio (HR) of P/AI 28 than that reported in the reference (2nd parity) group (HR = 0.74, p = 0.050). The repeat breeder cows inseminated at 76–80 and >80 temperature‐humidity index (THI) had significantly lower HR of P/AI 28 than those inseminated at the baseline (<70) THI value (HR = 0.73 and 0.30, p = 0.036 and 0.001, respectively). The current results indicate that the use of N‐CIDR synch protocol may achieve satisfactory pregnancy outcomes in repeat breeder cows.     

基于CAZAC序列的MIMO-OFDM定时同步算法

针对MIMO-OFDM系统定时同步中的精确度问题，提出一种基于CAZAC序列的定时同步方法。通过CAZAC序列优化帧的定时目标、准确度以及结构，使得帧和符号同步同时实现，简化定时算法。帧同步和符号同步的联合实现，降低了定时算法的计算量并能够准确定义信道的第一径，能够在时域实现整数频偏的估计，在提高同步精度的同时降低了系统的复杂度，通过仿真验证了算法在Rayleigh衰落信道中性能的明显改善。     

产后无发情和亚发情母牦牛激素诱导发情试验

选择怀孕母牦牛84头,在生产前后1个月进行补饲,其中40头在产后当年发情季节进行激素诱导发情试验,44头作对照;另选择60头自然生产的产后母牦牛在发情季节进行单纯的激素诱导发情试验,60头作对照.激素诱导发情方法是0 d注射氯前列烯醇0.2 mg,7 d后注射促黄体素释放激素A3 25 μg,连续3 d;在0和7 d进行直肠检查和血样采取,血样进行孕酮测定;测定处理时母牦牛卵巢状态,观察母牦牛发情配种受孕情况.结果显示,通过直肠检查和血浆孕酮测定,发现无发情状态的产后母牦牛占产后牦牛的63.33%和65%,亚发情的产后母牦牛占产后牦牛的36.67%和35%.采用氯前列烯醇和促性腺激素释放激素处理方案进行诱导发情,26.67%的产后母牦牛在处理后出现了发情;对怀孕母牦牛在围产期进行补饲,产后母牦牛在发情季节采用氯前列烯醇和促性腺激素释放激素诱导发情,有45.45%的产后母牦牛恢复了发情,而只补饲不进行激素诱导发情的母牦牛只有20%的母牦牛出现了发情;通过孕酮测定发现2组中激素诱导发情成功的母牦牛中,有68.18%和72%是处于亚发情状态的母牦牛.结果表明,氯前列烯醇和促性腺激素释放激素进行诱导发情的处理方案适合于产后亚发情状态的母牦牛.     

不同体况绵羊同期发情处理试验研究

通过两年三批次不同体况绵羊不同药物同期发情处理试验,分别对CIDR栓＋PG、CIDR栓＋PMSG、PG三种处理的发情率和发情时间进行比较分析,试验表明绵羊营养状况对不同药物同期发情处理均有较大影响,在营养较好条件下三种处理均可取得较好的同期发情效果,营养不良三种处理同期发情效果均变差,在相同条件下以CIDR栓为主的处理较PG处理发情率较高,且发情快而集中。综合考虑发情率和处理成本,在处理羊营养状况中等以上PG处理具有成本低操作简单的明显优势。