高校图书馆开展"阅读优质服务月"活动的实践与思考

在"世界读书日"之际,我校图书馆为了"营造校园阅读氛围,延伸图书馆的服务功能",开展了以"书籍滋养心灵,阅读充实人生"为主题的阅读优质服务月活动,活动内容丰富,活动效果受到读者的广泛欢迎,总结活动规律,将会为今后开展此类活动留下宝贵的经验.     

我国农村生育率对家庭人力资本的影响与对策

利用统计年鉴数据对我国农村生育率对家庭人力资本的影响进行实证分析,表明随着农村生育率下降,农村居民家庭人力资本呈现出不断上升趋势。在分析制约农村生育率下降迟缓的深层次经济与社会文化因素的基础上,提出应发展农户经济,改变农村生产经营方式,加快农村城市化进程,加快农村社会养老保障建设等对策,以降低农村生育率。     

奶山羊精子体外获能异体受精试验

关于哺乳动物体外受精的研究,已经历了120多年,直到80年代才获得了第一例“试管家畜”。近年来,尽管“试管婴儿”平均每天有4例问世,但到1990年4月10日为止,全世界获得的“试管家畜”仅有130例,其中“试管牛”54头,“试管猪”52只,“试管绵羊”23只,“试管山羊”只有1只。 为了克服山羊体外受精的难点,Rao等将山羊输卵管卵母细胞输入事先经子宫输入新鲜羊精的假孕兔输卵管,培养24～36h,有37.0％完成了异体受精。将这些受精卵移植给9只受体羊后,有1只正常分娩,获得了首例异体受精山羊羔。我们将超排羊输卵管卵母细胞移入事先经阴道输入新鲜羊精的假孕兔输卵管,获得了44.8％的异体受精率。但迄今尚未证实,山羊体外获能的精子与超排卵母细胞在假孕兔输卵管内能否完成受精过程和产出正常后代。本试验旨在研究山羊体外获能的精子与超排的输卵管卵异体受精及受精卵移植后产羔的可能性。     

马尾松“小阳春”集约造林试验阶段报告

利用每年11月份(俗称“小阳春”)适宜的温湿度进行马尾松栽植,造林成活率达93％,并有利于根系恢复,提前萌动,延长生长期,增加生长量,根系活力、叶绿素含量等生理特征值明显提高。同时,扩大了适宜造林的时间范围,缓和了春季造林劳力的紧张状况,有利于当年补植和避开春季造林的不利条件。     

青藏高原东北边缘亚高山桦木林种群年龄结构

基于10个典型样地的调查数据,对白桦、红桦、糙皮桦3种天然分布于青藏高原东北边缘亚高山带的主要桦木种群年龄结构进行了测度分析．结果表明,3种桦树的年龄结构较复杂,白桦和糙皮桦均属于增长型(发育的前期)或稳定型(发育的中期),而红桦的不同群丛属于增长型(发育的初期)或始衰型(发育的中后期),不同群落之间差异明显; 聚类分析结果显示,青藏高原东北边缘桦木林年龄结构大致可以分为5类,中华柳—糙皮桦林单独聚为第1类,桦叶荚蓬—白桦林和辽东栎—山杨—白桦林聚为第2类,箭竹—白桦林、糙皮桦纯林、红桦纯林、山杨—白桦林聚为第3类,白桦纯林单独聚为第4类,箭竹—红桦林和青杆—白桦林聚为第5类．出现以上情况,不仅与群落本身的性质有关,而且与人为干扰和地区环境差异有关．因此,为保护该地区桦木林,不但要进行适当择伐,减少人为干扰,而且应对其进行长期的定位监测．     

山西瘦肉型猪新品系(SD-Ⅰ系)6月龄体重遗传趋势分析

用混合模型ＢＬＵＰ法对山西瘦肉型猪新品系（ＳＤ Ⅰ系）选育过程中０～４世代４０头公猪的４４７头后裔６月龄体重进行了遗传趋势评估。结果表明：群体平均育种值随世代的增加而增加，说明ＳＤ Ⅰ系猪选育过程中所采取的育种措施是有效的。各世代间环境条件基本一致，且除０世代外，对表型值都有正的效应。继续进行选育，６月龄体重尚有提高的可能。     

Estimation of Genetic Parameters and Analysis of Season Effects and Age Effects for Semen Traits in Landrace Boars

The purpose of this study was to estimate the genetic parameters of semen traits of Landrace boars in South China and to analyze the influence of the age and season of semen collection on semen traits, so as to provide theoretical basis for formulating reasonable boar breeding program. The Asreml-R was used to analyze the 107 221 semen data of 1 605 Landrace boars from 2 AI stations in Southern China, the single-trait repeatability animal model was used to estimate the variance components, heritability and repeatability of each semen traits, two-trait repeatability animal model was used to estimate genetic correlation and phenotypic correlation of semen volume, semen density, sperm motility and percentage of abnormal sperm. The general linear model of R language program was used to analyze the influence of age and season of semen collection on semen traits. The results showed that the semen volume and percentage of abnormal sperm had medium heritability (0.23 and 0.38), and the variation coefficient of percentage of abnormal sperm was 85.42%, while the other traits had low heritability (0.07-0.19). Semen volume-semen density and sperm motility-percentage of abnormal sperm had extremely significantly negative genetic correlation(-0.77 and -0.90, respectively). Semen density-sperm motility showed extremely significantly positive genetic correlation (0.50). The influence of the age of semen collection on semen traits was significant(P<0.05). After boars reached sexual maturity, semen volume showed a significant increase, semen density and percentage of abnormal sperm showed a general decrease, and total sperm number and functional sperm number were significantly higher in the 13-18-month of age group than those in the other groups (P<0.05). The semen density was the highest in spring, and the total sperm number and functional sperm number were significantly higher in autumn and winter than those in spring and summer (P<0.05). In conclusion, the semen volume and percentage of abnormal sperm of Landrace boars can be selected as candidate traits. In the boar production management, boar whose semen production after 36 months of age decline, will be considered to update. Boar semen quality was significantly higher in autumn and winter than those in spring and summer. It is suggested that cooling work should be done in advance in Southern China in summer.     

Effect of extra maternal feed supply in early gestation on sow and piglet performance and production and meat quality of growing/finishing pigs

The influence of differentiated extra maternal feed allowance during early gestation on maternal performance and postnatal development of the progeny from gilts and sows was investigated. Four different feed allowances of the same diet (Control [C], +35% [T35], +70% [T70], +100% [T100]) were assigned to 20 crossbred gilts (Swedish Landrace×Swedish Yorkshire), which continued as sows with the same feed allowance the following parity. The progeny was uniformly raised and slaughtered at a live weight of 110 kg. Additional maternal feed allowance resulted in significantly more weaned piglets per sow but not per gilt. Piglet numbers did not increase from T35 to T70/T100. Piglet birth weight did not increase due to maternal feeding. The intra-litter variation in piglet birth weights was similar between the treatments. Independent of the additional feed allowance, all gilts and sows had similar weights after weaning and had good body condition. The growth rate of progeny from sows was negatively related to maternal feed supply; for progeny from gilts, no clear trend of nutritional influence could be observed. Carcass and technological meat quality was not affected by maternal feeding treatment. Birth weight positively affected later growth performance (daily weight gain), carcass quality (lean meat content, back fat, proportion of muscles in ham/loin), whereas technological meat quality was unaffected.     

B6-Co与B6小鼠眼睑角质形成细胞的原代无血清培养及比较研究

为进一步研究B6-Co小鼠眼睑发育缺陷机制,首次培养了小鼠眼睑角质形成细胞,并对B6-Co和B6小鼠眼睑角质形成细胞的迁移能力进行划痕实验分析,FITC-phalloidin染色比较B6-Co和B6小鼠肌动蛋白细胞骨架.结果表明,B6-Co小鼠眼睑角质形成细胞迁移的数目和距离明显少于B6小鼠.细胞骨架异常,B6-Co小鼠眼睑闭合不全(EOB)是由小鼠眼睑角质形成细胞迁移缺陷造成的.     

梅花星猪类群种质分子特征研究

利用PCR-RFLP等技术检测了湖北省黄梅县梅花星类群49头猪的ESR、FSHβ(影响产仔数)、TEF1(生长速度)、LPIN1、H-FABP(肌内脂肪含量),MC4R、CMYA1(背膘厚度)等7个候选基因的多态性.结果表明,梅花星猪类群中上述7个候选基因均有丰富的多态性,特别是肌内脂肪含量有利基因的基因频率较高,是其肉质优良的分子基础.其他性状相关基因的杂合子频率也较高,通过和已有的研究对比,初步分析梅花星猪类群受外来猪杂化程度严重,本研究为梅花星猪遗传资源的保护和利用提供了科学依据.