部分梅花品种主要观赏性初探

依据梅花的花形、花色、花瓣及花萼器官的主要观赏特征 ,对昆明市黑龙潭公园内的“龙泉探梅”梅花专类园收集的 8个类型中的部分栽培品种进行随机取样调查 ,分析其观赏特性及观赏价值 ,为进一步探讨梅花在园林造景中的应用提供参考。     

西部地区主要猪品种与野猪遗传聚类分析

对八眉猪、内江猪、荣昌猪、汉江黑猪等西部地区地方品种和汉中白猪、长白猪、大白猪、杜洛克猪等8个猪品种以及野猪基因组DNA、混合DNA样进行了RAPD分析。根据8个多态引物的扩增结果计算了遗传距离指数并进行了UPMGA聚类分析。结果表明：长白猪与大白猪亲缘关系最近，八眉猪和汉江黑猪次之，而野猪与长白猪的遗传距离最远。综合考虑现行的分类结果及前人研究结果，认为内江猪、八眉猪和汉江黑猪为一类型，荣昌猪和汉中白猪可划分为同一类型，但对野猪与其他品种的亲缘关系应作进一步分析。     

Comparison of performance of F1 Romanov crossbred ewes with wool and hair breeds during spring lambing under intensive and extensive production systems

The objective was to evaluate wool (Dorset and Rambouillet) and hair (Dorper, Katahdin, and White Dorper) breeds for their ability to complement Romanov germplasm in two distinct production systems by estimating direct sire and grandsire effects on lamb growth, survival, and ewe productivity traits. Rams of the five breeds (n = 75) were mated to Romanov ewes (n = 459) over a 3-yr period to produce five types of crossbred lambs (n = 2,739). Sire breed (P > 0.06) did not impact body weight or survival traits of the first-generation crossbred (F1) lambs. The productivity of retained crossbred ewes (n = 830) mated to Suffolk and Texel terminal sires was evaluated at 1, 2, and 3 yr of age in each production system. In the intensive production system, labor and harvested feed were provided for sheep that lambed in March in barns, and ewes were limited to rearing two lambs with additional lambs reared artificially. Ewes in the extensive production system lambed in May on pasture and were responsible for rearing all lambs born with no labor or supplemental feed provided before weaning. A total of 1,962 litters and 4,171 lambs from 2,229 exposures to two terminal sire breeds (Suffolk and Texel) were produced in the experiment. Crossbred ewes in the intensive production system were mated in October, resulting in larger litter sizes than crossbred ewes mated in December for the extensive production system. However, single- and twin-born lamb mortality was similar between the two systems that differed greatly in labor, feed, and facilities. Lambs produced in the intensive system received concentrate feed from an early age and were heavier at 24 wk of age than lambs produced in the extensive system. These outcomes resulted in greater 24-wk litter weight in the intensive than in the extensive system (P < 0.0001). Unexpectedly, the relative performance of crossbred types did not differ importantly between production systems. White Dorper × Romanov crossbred ewes had numerical advantages in productivity in each system; however, differences between ewe types were not significant. In the extensive system, without labor and shelter at lambing or supplemental feed until weaning, 3-yr-old crossbred ewes of all types averaged 1.78 lambs marketed per ewe lambing, and 40% of the ewes that gave birth to triplets weaned their entire litters. These results document that prolific sheep and extensive systems can be successfully combined if appropriate crossbred types are used.     

The SNPs Analysis of the Exons of Three Genes of MyoD Gene Family in Seven Swine Breeds （Line）

The study objects includes seven swine breeds： Minzhu, Sanjiangbaizhu, Yorkshire, Landrace, Junmuyihao, Duroc and Double muscle Yorkshire. According to the sequences of MyoG, MyoD and Myf5 of swine in GenBank, seventeen pairs of primers for MyoG, MyoD and Myf5 were designed. PCR-SSCP technology was applied to detect SNPs of the exons of the three genes. The results showed that no polymorphism was in MyoG and MyoD, and some SNPs were in three exons of Myf5. There was one mutant site in the first exon of Myf5 （G → C）, three mutant sites in the second exon of Myf5 （C → A, A → G and G → A）; in the third exon of Myf5, there was one base A deficiency at 3 387 bp, three bases T deficiency at 3417 bp, one mutant site at 3443 bp （T → C）. This study obtained a tendency conclusion that gene frequency of allele M of Myf5 on the one hand is positively correlated with lean meat percentage, on the other hand is correlated with the orientation of selective breeding; it also deduced that allele F is possibly correlated with high lean meat percentage. Through statistical analysis, allele A, B, C of Myf5 have no obvious correlation with lean meat percentage of different swine breeds. In addition, the high polymorphism of Myf5 showed that seven swine breeds are rich in genetic variation, and have high selective competency.     

江西地方品种鸡禽白血病病毒及鸡白痢沙门氏菌感染状况的研究

禽白血病毒(ALV)和鸡白痢沙门氏菌(SP)均可以垂直传播。通过禽白血病病毒(ALV)J亚群抗体和群特异性P27抗原的商品化ELISA检测试剂盒和全血平板法等调查了江西省13个种鸡企业的8个地方品种鸡群ALV和SP的感染情况,结果显示:ALV-P27抗原、ALV-J抗体均有检出,江西省地方鸡ALV-J亚型感染相当严重,迫切需要净化。江西地方品种鸡白痢沙门氏菌感染率相差较大,同一品种鸡在不同场之间的SP感染率差异明显。生物安全措施会影响鸡白痢的感染情况,在鸡白痢的净化过程中,采取严格的淘汰制度的同时,必须加强饲养管理措施来控制鸡白痢的发生。     

杜泊绵羊对我国本地绵羊杂交改良的初步效果

目前我国绵羊无论存栏数还是产肉量均居世界首位,但各地方品种众多,与世界优良肉用绵羊相比普遍体重较小、生长慢。2001年以来我国引进了著名肉用绵羊—杜泊绵羊,各地相继开展了杜泊绵羊对本地绵羊的杂交改良,都取得了显著效果,杂交后代在生长速度及产肉性能方面都有很大的提高,为加速我国肉用绵羊业的发展开创了新的途径。     

《中国生物多样性国别研究报告》中家畜禽品种英汉对照名称

《中国生物多样性国别研究报告》中家畜禽品种英汉对照名称陈幼春储明星（中国农业科学院畜牧研究所，北京１０００９４）《中国生物多样性国别研究报告》自１９９３年６月开始拟稿，历时三年，于１９９６年６月２６～２８日在中国林业科学院完成终审，此报告是根据李鹏总...     

两种猪种对含全脂大豆抗营养因子饲粮的消化率反应

试验用 2× 3析因试验设计 ,研究了含有 2 0 %热处理全脂大豆、2 0 %生全脂大豆和不含有任何大豆及大豆产品的等能量、等氮和等赖氨酸水平的 3种饲粮对东北民猪仔猪和长白仔猪的饲粮养分消化率的影响。试验结果表明 :东北民猪仔猪对干物质、粗蛋白质、粗脂肪 (P <0 .0 5 )、粗纤维、无氮浸出物 (P <0 .10 )的消化率显著高于长白仔猪 ;3种饲粮之间 ,热处理全脂大豆饲粮的干物质、粗蛋白质、粗脂肪、粗纤维、粗灰分、无氮浸出物的消化率高于生全脂大豆饲粮和对照饲粮。     

中外品种猪的肉质性状差异及其形成机制探讨

肉品质是猪的重要经济性状。随着人们生活水平的提高,消费者对优良的猪肉品质越来越重视,优良肉质性状形成与营养调控已成为畜牧学研究的热点。影响肉质性状的因素较多,且中外品种猪之间的肉质性状差异很大,这为研究肉质性状差异的形成机制提供了很好的素材。本文综述了国内外相关研究进展,比较了中外品种猪的肉质性状差异,并对其形成的遗传机制进行了探讨,旨在为生产更多满足人们需要的优质肉产品提供参考。     

The Genetic Diversity and Phylogenetic Relationships of Five Guangxi Pig Breeds and Three Exotic Pig Breeds by Analysis of mtDNA D-loop Sequences

In order to compare the genetic diversity and phylogenetic relationships between Guangxi pig breeds and three exotic pig breeds,one pair of primers was used to amplify 85 mtDNA D-loop sequences of five Guangxi pig breeds (Bama Xiang pig,Dongshan pig,Guizhong spotted pig,Luchuan pig,Huanjiang Xiang pig),and we downloaded 45 mtDNA D-loop sequences of three exotic pig breeds (Duroc,Yorkshire,Landrace) from GenBank.Then the haplotype,genetic diversity and phylogenetics analysis were carried out.The results showed that 38 haplotypes were identified in 130 sequences,and the mean distances among Guangxi pig breeds were smaller than that among Duroc,Landrace and Guangxi pig breeds.The NJ phylogenetic tree classified all samples into two clusters.One contained all of Guangxi pig breeds and partial Yorkshire,the other was composed wholly of exotic pig breeds,which mean there were two distinct maternal origins.In the cluster of Guangxi pig breeds,Luchuan pig were clustered,and the others were rather dispersive.It indicated that Luchuan pig had simple maternal bloods,and the other breeds had complex maternal bloods,and they had gene flow with each other.The maternal pig resources in Guangxi were not affected by the introduction of exotic pig breeds,and they were still suitable for use as a female parent in their development and utilization.