公猪信息素28天诱情法对后备母猪初情期的影响

1 引言 推动母猪群繁殖性能的最关键因素之一是对后备母猪的管理和培育.每年约有 40％～50％的母猪被淘汰,有些母猪一生仅断奶30至40头仔猪.由于寿命短而导致的更高更新率会增加所需后备母猪的数量.所以,制定管理实践措施以识别具有最大生命周期性能潜力的后备母猪对于生产系统的生产力至关重要.即便是对后备母猪管理的微小改进...     

公猪效应对小母猪初情期诱导的作用

小母猪与公猪接触可诱发其提早进入初情期,因此在适当的管理和营养条件下,小母猪与公猪接触后可在5月龄时出现初情期。如果小母猪与生长猪一起饲喂,则只有1%在7月龄体重达到100-104千克时可达到初情期。一般来说,大多数140日龄以上的小母猪会对接触公猪出现反应而表现发情。从接触公猪到出现初情期的时间随着小母猪从160日龄增加到200日龄而缩短,但如果在160日龄之前接触公猪进行刺激,则小母猪达到初情期的日龄及体重都会增加,而且对繁殖性能没有任何改进作用。因此,应该在小母猪达到160日龄时让其接触公猪进行刺激。一般与成年公猪（8-11月龄）接触5-30分钟/日可迅速引起小母猪达到初情期。     

公猪精液异常的鉴定

猪人工授精技术是促进猪的繁殖育种和提高养猪业经济效益的一项重要的技术。精液品质、授精时间的确定以及母猪输精后的管理等是与其繁殖性能密切相关,直接影响到母猪生产性能的最佳发挥。我们在评价精液品质方面主要集中讨论精子形态学。尽管在影响猪的繁殖性能的人工授精技术诸因素中,精液品质占33％,但由精液品质引起的生产性能下降问题(如窝产活仔数显著降低)越来越受到重视(见表1)。 精液品质与精子的成熟期和精液的加工有     

如何提高公猪在夏季的繁殖性能

如何提高公猪在夏季的繁殖性能野猪的性兴奋高峰出现于冬季，即日照时间最短的季节。有可能家猪也保留着这种季节性的光照周期规律。１９９１年进行的试验表明了季节因素对杜洛克公猪精子生成量的影响（表１）。由表１可见，公猪的确是在冬季的射精量最大，春夏季节的精子...     

种公猪营养与繁殖性能

营养与繁殖性能的关系越来越受到人们关注,而种公猪的繁殖性能对养猪生产至关重要。研究表明营养是影响种公猪繁殖性能的主要因素,营养缺乏使得种公猪繁殖性能低下。文中主要综述了能量、蛋白质与氨基酸、维生素、矿物质等营养素与种公猪繁殖性能关系以及种公猪的营养需要等。     

公猪繁殖生物学和繁殖性能

公猪处于不良条件下时,正常的精子发生过程会根据应激的严重程度和持续时间而以一定的方式发生变化。公猪处于中等程度应激之下数天时间,从理论上说,精子的发生过程会呈现类似于图1所示的方式。中等程度应激的例子也许就是环境温度数天时间处于温度适中区之外的情况,或者是引起体温升高数天的温和疫苗反应。一般来说,应激开     

公猪部分繁殖相关性状的研究进展

公猪的繁殖相关性状包括性行为、生殖器官形态大小、精液质量及后裔繁殖性能等。本综述从遗传学的角度出发,对以下5个方面进行了详细的阐述和总结:1)公猪的性行为;2)公猪的精液质量及其与繁殖性能的关系;3)生产性能与公猪繁殖相关性状的关系;4)公猪繁殖相关性状的遗传力。旨在为更好地管理公猪站、提高公猪站的生产力和经济效益提供一点理论基础,以供同仁参考。     

结扎公猪用作诱情公猪应该注意的问题

在猪场中,公猪出生后什么时间结扎比较合适?后备母猪什么时候使用结扎公猪进行诱情?很多猪场将诱情的结扎公猪放在后备母猪圈中饲养,是要一起饲喂?还是需要单独饲喂?公猪可以在很小的时候就直接结扎,例如产房内结扎,然后再把结扎的小公猪养大。后备母猪诱情可以选择在150～170日龄之间,在每个圈舍里放一头结扎的公猪,长期跟母猪一起饲养,这样既不用担心结扎公猪的配种问题,又可以节省很多劳     

浅析种公猪使用年限的影响因素

近年来,种公猪的研究不再是单一的营养问题,更为重要的是繁殖性能和使用年限的问题。种公猪的好坏直接影响着整个猪场的效益。合理延长种公猪的使用年限,对猪场生产有很重要的实际意义;如节约种公猪养殖成本,提高母猪的配怀率和产仔数,以及提高整个猪群的稳定性。文章对影响种公猪使用年限的几种因素进行了简要概述。     

公猪繁殖性能评定

随着规模化养猪业的发展及人工授精技术的普及,公猪繁殖性能已是影响猪场经济效益的重要因素。如何准确评定公猪的繁殖能力,保证人工授精效果,进而保证母猪的繁殖性能的发挥,是养猪人工作中的重要环节。生产实践中最常用的是通过显微镜对猪精细胞水平进行检测。科研人员也在一直研究影响人工授精效果的因素,将精液的检测从细胞水平上升至分子水平,再用分子标记手段将公猪繁殖性能由检测提前至预测,最大限度地保证公猪的繁殖性能,保证优良公猪的性能得到最大程度的发挥。文章从精液品质、人工授精效果、分子水平检测、标记物等几个方面介绍公猪繁殖性能评价时需要衡量的指标,为公猪繁殖性能评定提供参考。     

环境温度对发酵床养殖公猪繁殖性能的影响

微生物发酵床养殖是一种生态养殖模式,在冬天具有很好的保暖作用,减少了日粮的损耗,但在夏天,缺少散热的功能,对育肥猪和种猪的养殖影响较大。实验对某微生物发酵床生态养猪场的4头种公猪,通过连续观测公猪舍环境温度、垫料温度及公猪的精神状态,检测公猪血液生化指标、精子活率、精子质量、精子密度及生化指标项目。结果发现1号公猪的总蛋白水平较高,其它生化指标差异不显著;4头公猪中只有4号公猪精子活率达到70%,其余公猪精液中精子活率低于10%,大量死精。结果表明微生物发酵床养殖对公猪繁殖性能的影响较大。     

The association between disease and profitability in individual finishing boars at a test station

Endemic diseases in finisher herds are considered to be costly for the pig producer. We investigated the effect of diseases on the profit margin using data from a Danish boar test station (n = 5777) collected from July 2002 to December 2004. Boars reaching a target slaughter weight of at least 80 kg were included in the study. Oral and parenteral treatments were used as indicator of disease in the finishing period and, pathological lesions were used as indicator of disease at slaughter. Profit margin was calculated individually for each boar as the difference between the total revenue and the variable costs. A multivariable hierarchical model was constructed to investigate the association between the risk factors: oral treatment (yes/no), parenteral treatment (yes/no), pathological findings (yes/no), breed (Duroc, Hampshire, Landrace, Yorkshire) and weight at 4 weeks with the outcome variable: profit margin. The results showed that treatment in the finishing period had a negative effect on the profit margin. According to the least square means estimates, boars that were treated parenterally had a reduction in the profit margin of 2.24 €. This corresponded to a reduction in the profit margin of 17%. Boars treated orally had a reduction of 0.88 €, which corresponded to a reduction in the profit margin of 7%. Pathological findings, breed and weight at 4 weeks were also significantly associated with the profit margin. The effect of pathological findings was influenced by breed and caused a reduction in the range from 0.54 to 2.41 € (corresponding to a reduction in the profit margin ranging from 4 to 20%). The results were robust to changes in price of a 30 kilogram piglet and, relatively robust in regard to changes in the feed price. However, price per kilogram carcass weight appeared to influence the economic effect of oral and parenteral treatment and pathological findings on the profit margin. The effect of oral and parenteral treatments was also sensitive to changes in medicine prices.     

Pampas deer (Ozotoceros bezoarticus) courtship and mating behavior

Background

Pampas deer, Ozotoceros bezoarticus (Linnaeus 1758), is a South American grazing deer categorized as "near threatened". However, knowledge about pampas deer behavior including courtship and mating is scarce and incomplete. The aim of this study was to characterize the courtship and mating behavior of the pampas deer (Ozotoceros bezoarticus), an endangered species from South America.

Methods

We performed focal observations of 5 males allocated at the Estación de Cría de Fauna Autóctona Cerro Pan de Azúcar, Uruguay, 4 times a day from 5 to 20 minutes each time on a daily basis from February to May. During that period we recorded all courtship and mating behaviors, as well as quantified the frequency of the specific behaviors shown. As mating were rarely observed, we recorded that behavior when it was observed in the context of other studies performed in the same population during the following 2 years.

Results

During the observation period we recorded 928 courtships and 5 mating periods. In addition, we recorded 10 more matings performed during other studies, totaling 15. The duration of each mating calculated from the 15 recordings was 3.9 ± 0.4 s, and the total period of female receptivity (from first to last mating acceptance) was 8.2 ± 1.1 min. Main observed courtship behaviors in males were “chase” and “ostentation”, while the most observed close to mating were “chinning”, “raised head” and “anogenital sniffing”. The most observed behaviors in females during the mating period were “vulva exhibition” and “move away”.

Conclusion

This is the first detailed report in pampas deer mating behavior. Estrus lasted only 8 min accepting only 3 short copulations per estrus. However, female behavior during courtship can be characterized as highly proceptive.     

Attitudes of Swiss consumers towards meat from entire or immunocastrated boars: a representative survey

Male piglets are castrated in order to prevent boar taint in pork. The surgical intervention is currently done without anaesthesia. Growing public concern about the welfare issue of this procedure forces the meat industry to evaluate alternative methods. The acceptance of such methods was studied in Switzerland within a large representative survey on the image of Swiss meat. Five questions were aimed at our subject. It was found that only a small part of the population has actually experienced boar taint. Nevertheless, the majority would not buy products made from tainted meat even if the absence of any perceivable boar taint and identical quality with current products could be guaranteed. The acceptance of meat from immunocastrated animals was low. Among the proposed four alternative methods, the production of entire males (with two options regarding processing of the tainted meat), immunocastration and castration with anaesthesia, only the last one seems to be acceptable to the interviewees.     

Production of inhibin A and inhibin B in boars: changes in testicular and circulating levels of dimeric inhibins and characterization of inhibin forms during testis growth

We investigated the production of inhibin in boars from the infantile to pubertal periods by: (1) measurement of testicular and circulating levels of inhibin, (2) characterization of inhibin forms and (3) localization of inhibin subunits in the testis. Total inhibin levels in the testis increased until 8 weeks of age but then declined to much lower values at 15 weeks. Testicular inhibin A and inhibin B were high until 8 weeks. Circulating levels of total inhibin and inhibin A were also high until 8 weeks, then declined from 10 weeks; inhibin B was not detected, because of low sensitivity of the inhibin B assay. Analyses of inhibin A and inhibin B levels in the eluted fractions obtained from testes after immunoaffinity chromatography and SDS-PAGE showed the presence of a peak of approximately 45 kDa until 10 weeks of age. As the boars aged, the levels of inhibin A and inhibin B increased in the molecular weight region of 29–31 kDa. The fractions corresponding to 29 and 30 kDa suppressed FSH release from rat pituitary cells, but the 45 kDa fraction had no FSH-suppressing activity. Total amounts of inhibin A isolated from the SDS gels were similar to those of inhibin B until 10 weeks of age, but were three times higher than those of inhibin B between 15 and 25 weeks. Further fractionation by reverse phase high-performance liquid chromatography revealed that the 29–31 kDa immunoreactive material was composed of mature forms of inhibin A and inhibin B, in addition to a 26 kDa monomer. Immunohistochemistry indicated that positive immunostaining for the subunits was observed in Sertoli cells from the infantile to pubertal periods. Elongated spermatids also showed positive signals at age 25 weeks. These results clearly indicated that: (1) the boar testis has the ability to produce inhibin A and inhibin B during the infantile period but inhibin A is the predominant form towards puberty and (2) the molecular weight forms of inhibin and the sites of production of inhibin change with testicular development.     

母猪日粮纤维的营养研究进展

日粮纤维具有多种理化特性,日粮中添加适量的纤维可改善妊娠母猪的繁殖性能,降低刻板行为的发生率,防止便秘,降低无乳症的发生率,在养猪生产中具有重要的意义。本文主要介绍了日粮纤维的定义、理化特性及其对母猪的繁殖性能、行为和健康水平的有益作用、不利影响及可能的作用机制。     

种公猪选育技术及提高选育效果的措施

种公猪的优质选育能得到更好的品种,降低生产成本,提高生产效率,种公猪的选育成为了种猪选育的一大重要项目。本文概述了我国种公猪选育的一般原则与方法,指出了种公猪性能测定的现状,表述了种猪选育的新技术,详细介绍了种猪选育性能测定过程中的方法及注意事项,并提出了一些提高种猪选育效果的措施。     

催情散中总多糖、总黄酮及4种活性成分的含量测定

目的：建立催情散中总黄酮、总多糖含量测定方法,并建立同时测定朝藿定A、朝藿定B、朝藿定C、淫羊藿苷有效成分含量方法,为催情散的质量控制提供全面的依据。方法：运用比色法测定催情散中总多糖和总黄酮的含量,应用高效液相色谱法(HPLC)分析催情散中主要成分并测定其含量。结果：不同生产厂家的催情散中主要化学成分的含量存在一定差异,催情散中总多糖平均含量为3.35 %,总黄酮平均含量为1.30 %,催情散中总黄酮中朝藿定A、朝藿定B、朝藿定C和淫羊藿苷的平均含量分别为0.0137 %、0.0131 %、0.1106 %、0.0764 %。结论：建立了催情散中总多糖、总黄酮及4种活性成分测定方法,此方法具有较好的稳定性和重复性,可以作为催情散质量控制的标准。     

人工散养条件下对混养火烈鸟繁殖行为的初步观察

2000年5月～2006年7月连续6 a对香江野生动物园人工散养条件下不同品种混养的火烈鸟繁殖行为采用随机观察,个别焦点跟踪和持续跟踪观察等方法进行了系统的研究,结果表明除繁殖期不同外,混养的古巴火烈鸟与大火烈鸟的繁殖行为相似;混养的古巴火烈鸟没有与大火烈鸟发生过交配行为.