Progestin and prostaglandin for estrous synchronization in beef heifers

Seventy-eight Simmental-Angus-Hereford crossbred yearling heifers, in 1983, and 99 similar heifers, in 1984, were used to compare two estrous synchrony regimens. One treatment group (SMB) was synchronized using the commercially available Syncro-Mate-B procedure, which involved placing a norgestomet implant in the ear for 9 d and giving an injection of norgestomet and estradiol valerate at the time of implantation. A second group (PR + PG) was given a norgestomet implant (PR) for 7 d and a 5-mg injection of alfaprostol (PG) at implant removal. Percentage of heifers cycling during the synchronization period and percent conceiving in 5 d or 30 d were not different (P greater than .10) due to treatment. The interval from implant removal to onset of behavioral estrus was shorter (P less than .01) for the heifers treated with SMB than for the heifers treated with PR + PG (42.8 vs 58.0 h). The group treated with SMB had a more uniform synchrony of estrus than the group treated with PR + PG. The effect of day of the estrous cycle at implantation on hours to estrus after implant removal was determined by a regression analysis, which showed a linear response for the SMB group with a slope of .78 (P = .09); the PR + PG group regression was cubic (P less than .01); this also indicated a more uniform response by the SMB group. These results indicate that the combination of norgestomet and alfaprostol produced more variation in interval from treatment to estrus than the Syncro-Mate-B procedure.(ABSTRACT TRUNCATED AT 250 WORDS)     

牛胚胎移植受体牛同期发情效果分析

牛胚胎移植过程中,受体牛同期发情处理是重要的环节之一,而处理效果常以发情率和黄体质量作为判定标准。本试验在2003年10月采用不同的方法对受体牛进行同期发情处理,得到不同的效果,即:按二次肌注PG法处理受体牛44头,     

发情周期中奶山羊下丘脑-垂体-卵巢轴催产素的免疫组化定位

用免疫组化ABC法,对发情周期中奶山羊下丘脑-垂体-卵巢轴催产素(OT)分布进行了观察研究.结果表明,下丘脑中分泌OT的神经元主要分布在室旁核和视上核,在穹窿周核、腹内侧核、腹外侧核、交叉上核、背内侧核、乳头体、下丘脑外侧区、下丘脑前核等核团也有一定数量的阳性神经元;阳性神经纤维仅见于室旁核、下丘脑前核、视上核等少数核团,在正中隆起和第3脑室室周可见到一定数量的阳性神经纤维.在垂体前叶未见到OT免疫反应阳性产物,自垂体柄和正中隆起的一侧可见到平行排列的OT阳性神经纤维断续地延伸至神经部.卵巢的卵泡及间质未见OT免疫阳性反应,,在黄体组织中存在数量较多的免疫反应阳性细胞,阳性细胞主要呈圆形、卵圆形,小梁两侧及黄体中央近腔区域的阳性细胞呈长梭形,有相当数量的阳性细胞具有突起.连续切片HE染色对照观察显示,黄体中OT主要由大黄体细胞产生,但小黄体细胞也存在OT免疫阳性反应.     

四川省亚热带湿润气候区紫花苜蓿的生产特点

分析了四川亚热带湿润区的气候,土壤和地形特征,指出了紫花苜蓿在这一地区的主要受限因素,并提出在四川湿润地区推广种植紫花苜蓿要注重抗湿、抗热、耐酸品种的选育,同时要提高田间管理水平。在紫花苜蓿的利用上,要以饲草利用为基础,采用菜用、蜜用相结合的方式,提高经济收益,以解决紫花苜蓿在南方地区生产,管理和运输成本高的问题,扩大紫花苜蓿在四川的种植规模。     

南方湿热气候地带提高肉牛育肥效果的生产环节控制

为了给南方湿热气候地带肉牛的育肥提供参考,文章从肉牛育肥生产的4个重要环节论述了如何选择开始育肥的时间、育肥的期限、架子牛的始重和育肥饲料,以提高在南方(尤其是岭南地带)肉牛育肥的生产效益。建议在岭南湿热地带育肥肉牛开始时间以10月下旬或11—12月份较佳;育肥架子牛年龄、体重应尽量接近,周岁以上犊牛年龄相差以不超过2～3个月为宜,体重差异应控制在1个标准差以内;育肥模式可选择秋末、冬春的非热季节3～6个月短期育肥、从第1年的1月底或2月初开始的跨年度12个月育肥和从第1年秋末开始的跨3个年度的18～24月的长期育肥3种育肥模式;育肥饲料应按照育肥阶段提前准备,渐进式地更换饲料品种类型和数量;并从牛的种质、驱虫防病、每日最佳投料时间和确定产品适时上市等方面提出了持续增加育肥生产效益的可选择环节。     

不同部位注射氯前列烯醇对南疆绒山羊同期发情的影响

同期发情技术是繁殖控制技术的重要内容之一,是指利用某些激素制剂处理,人为控制并调整母畜发情周期使之同期化的方法。使母畜在预定的时间内集中发情,以便有计划合理组织配种,有利于推广人工授精,减     

适于西南石漠化治理推广应用的草种

介绍了石漠化的概念及分布,阐述了石漠化治理工程对草种、灌木的基本要求以及适宜种植的牧草、灌木种类,给石漠化治理推广应用的草种提供了一定的基础.     

我国安哥拉山羊性能统一测定的实施建设

1 性能统一测定的必要性 目前，我国的陕西、山西、内蒙古、甘肃、四川等10省(区)饲养的纯种安哥拉山羊已达1 500余只，含有安哥拉山羊血液的各代杂种将近15万只(肖西山，1998)。然而缺乏全国统一的协调组织，对优秀种公羊不能共享，以致引进的安哥拉山羊利用效率低。其原因主要是由于我国安哥拉山羊发展时间较短，在组织管理上还不完善，不但没有产品马海毛的等级标准，而且也没有安哥拉山羊的品种标准(肖西山，1998)，在生产上存在着盲目选择种羊的现象。 对我国安哥拉山羊性能统一测定，是为了制定一个品种标准，打破省(区)间的界限，充分发挥现有种公羊的利用率，建立全国性的优秀种公羊登记和选育体系，从而促进我国马海毛生产。 2 美国安哥拉山羊性能测定的组织工作 据报道(Lewis和Shelton，1985)，美国得克萨斯州于1967年就开始了安哥拉山羊的性能测定工作，主要采取测定站集中测定。每年一次，大约在3月初至7月末这一段时间内进行。测定工作主要由得克萨斯农业实验站负责，同时邀请州内的安哥拉山羊生产者及农场主参与。 测定开始时，先是州内各地的参与者将待测羊只送往测定站，然后对被测山羊驱虫和肠毒血症免疫，再将被测羊只分养在各测定圈舍里。正式测定开始之前，要经过为期两周的调整期。在整个测定期，要定期进行药浴防螨。在饲养方面，所有羊只都采用自由采食方式。每年的日粮配合变动不大。整个测定期间，羊只的死亡损失及饲养费、医药费和剪毛所需花费都由各地参与者自行负责。畜主有权利随时去测定站察看自己的羊只，而且剪下的毛仍归畜主所有。测定完毕，在测定站安排1天的展览日，这一天可以得到有关被测羊只的一整套资料。另外还可能安排1天的拍卖日，各畜主可以自由出售自己的羊只。至此，一年一度的测定工作暂告结束。 测定站集中测定的优势是待测公羊事先在具有可比性的条件下进行饲养管理，而且要经过两周的调整期，因此有可能发现并利于保存最好的公羊；有利于客观地评价、比较各公羊，并及时掌握各羊只在一段时间内的变化情况，为对其进行改良和利用提供更多的依据；另外测定站有条件进行山羊饲料效率的测定，并进行有关研究。但是，这种测定法存在的一个严重问题是，来自各地的待测羊只之间差异很大，在某种程度上影响各性状在选择指数中的权重(Shelton，1987)，另外可能会引起各地山羊的疫病传播；且其测定容量小，受测公羊数量有限，测定成本也高。     

贵州黑山羊胚胎移植手术不同麻醉方法比较

为了筛选适合于贵州黑山羊胚胎移植手术的麻醉方法,试验以贵州黑山羊为试验动物,比较了速眠新Ⅱ注射液2种麻醉方法（肌肉麻醉和静脉麻醉）对山羊生理指标,麻醉山羊的诱导期、麻醉期、苏醒期,麻醉苏醒后山羊的采食、反刍及精神状况的影响。结果表明：2种麻醉方法下,麻醉效果优、良的山羊数量和生理指标无明显差异;速眠新Ⅱ注射液静脉注射麻醉时,山羊的诱导期、麻醉期和苏醒期均较短,在苏醒后0.5 h,90.0%的山羊可以采食,83.3%的山羊可以反刍,93.3%的山羊精神状况良好;苏醒后1 h基本上全部可以恢复正常;采用静脉注射麻醉山羊进行胚胎移植手术,速眠新Ⅱ注射液用药剂量小,且安全、有效,明显优于肌肉注射。     

论西南地区的草地生态建设

在阐述西南的地理位置以及草地资源特征的基础上,分析了西南草地建设对于生态环境、畜牧业及农业发展的重大作用,并提出了进行草地建设的一些措施.     

论西南地区的草地生态建设

在阐述西南的地理位置以及草地资源特征的基础上,分析了西南草地建设对于生态环境、畜牧业及农业发 展的重大作用,并提出了进行草地建设的一些措施。     

Change of daily milk yield during estrous period in Holstein cattle raised under Mediterranean climate

This study was conducted to determine the effect of estrus on the daily milk yield in Holstein cows and to investigate the chance of using the possible milk yield changes in determining the estrus. During the 3-year period of the study, 103 dairy cows were observed 4 days before and 4 days after daily milk yield of 240 estruses and a total of 2174 daily milk yields were evaluated. Variance analysis was used to determine the factors affecting the daily milk yield, and the LSD test was used for multiple comparisons. Insemination year, insemination season, number of lactation, milk yield group, and daily milk yield of lactation period were found to be significant (P?<?0.01). On the other hand, the effect of estrus days on milk yield was insignificant. In the days of estrus, the least square mean of milk yield is 31.0 kg, while the lowest and highest milk yields are 10.2 kg and 62.9 kg. The daily milk yield in the estruses decreased by an average of 300 g, which decreased to 400 g by continuing 1 day after the estruses. The next day, however, it increased rapidly by 600 g, and then dropped again, probably due to the effect of metestrus. It was found that, among all estruses, 31.3% of cows decreased their milk yield, whereas 26.5% of cows increased their milk yield. However, 42.2% of cows both decreased and increased their milk yield in different estruses. The interval between birth and the first insemination after were found to be longer (97.5 days and 92.9 days) at high milk-yielding cows compared to the low milk-yielding cows. According to the results of this study, daily milk yield changes could not be used as an estrus indicator.

     

超细品系羊非发情季节同期发情实用技术研究--配种公羊对同期发情效果的对比分析

对中国美利奴羊(新疆军垦型)超细品系乏情季节不同配种公羊对同期发情效果的影响作了对比分析.结果证明,成年公羊配种比周岁公羊好,1060、1063、1073号公羊的效果比1068、1069、1070、3021号公羊好.     

过渡地带高尔夫球场草坪建植技术的研究

过渡地带因其特殊的气候条件为高尔夫球场草坪的建植带来了一定的困难.通过草坪建植前床土及排水层的处理、草种的选择、混配和草坪苗期管理几个方面阐述了过渡地带高尔夫球场草坪建植的技术和方法。     

利用孕酮栓+PMSG+PG法对羊同期发情效果的试验研究

利用孕酮栓+PMSG+PG法对大群体羊进行同期发情处理,比较不同季节、地区、埋栓时间及品种对同期发情效果的影响。结果表明:该方法在春季、秋季和冬季对山羊均可获得较好的同期发情效果,并且发情时间主要集中于处理结束后的0～24 h和25～48 h;对于山区及平原的山羊,0—24 h及25—48 h同期率差异不显著(P>0.05);埋栓时间长短对于山羊在0—24 h、25～48 h及0～72 h的同期率差异均不显著(P>0.05);绵羊同期效果显著低于山羊(P<0.05)。     

Evaluation of luteolysis and estrous synchronization by a prostaglandin analog (Luprostiol) in Brahman cows and heifers

A trial was conducted to evaluate the ability of a prostaglandin analog, Luprostiol (LP), to synchronize estrus in Brahman cows and heifers. Animals were injected with either 0, 3.75, 7.5, 15 or 30 mg LP or 500 micrograms cloprostenol (CLP) on d 8 or 9 after estrus (d 0). All concentrations of LP (greater than 0 mg) and CLP caused luteolysis in cows and heifers, as indicated by a decline (P less than .01) in serum progesterone concentration after injection. Animals receiving 0 or 3.75 mg LP had a longer (P less than .04) interval to estrus after injection than did animals in other treatment groups. The proportion of animals exhibiting estrus by 120 h after injection was influenced by dose of LP (P less than .0001; 0, 3.75 mg less than 7.5, 15 and 30 mg and CLP) but not by age. Cows had a lower (P less than .01) progesterone concentration than heifers on d 10, 11 and 12 after LP-induced estrus. Progesterone concentration was lowest (P less than .01) on d 10, 11 and 12 after LP-induced estrus in cows given 15 mg LP or CLP. First-service conception rate was similar between cows and heifers, but it was lower (P less than .01) in animals given 15 or 30 mg LP. Both estrogen and LH concentrations were decreased (P less than .01) at the time of estrus by the 15 and 30 mg of LP. Luprostiol can cause luteolysis and estrous synchrony in Brahman cattle.(ABSTRACT TRUNCATED AT 250 WORDS)     

Seroprevalence of Mycoplasma hyopneumoniae in pigs in subtropical southern China

Enzootic pneumonia caused by Mycoplasma hyopneumoniae is a severe disease of pigs, causing significant economic losses to the pig industry worldwide, including the tropical and subtropical regions. In order to obtain the baseline prevalence of M. hyopneumoniae in pigs from intensive farms in southern China, double-sandwich enzyme-linked immunosorbent assay (ELISA) was used to detect M. hyoneumoniae antibodies in 460 pig serum samples collected from 12 administrative cities in China’s southern Guangdong province. According to the proportions of the infected animals, among the 12 intensive farms, only two of them showed no infection of M. hyoneumoniae and the seroprevalence ranged from 0% to 90%, with an averaged prevalence of 45.7%. The highest prevalence was found in breeding boars (68.8%), followed by sows (54.5%). These data showed that the infection of pigs with M. hyopneumoniae is severe, and boars might be more important carriers and transfers of M. hyoneumoniae than sows. Integrated strategies and measures should be taken to control the infection of pigs with M. hyopneumoniae in southern China.