脂尾去除对‘兰州大尾羊’和‘蒙古羊’生长性能及脂肪沉积分布的影响

为了研究脂尾去除对‘兰州大尾羊’和‘蒙古羊’生长性状及脂肪沉积分布的影响,选取发育正常、年龄、体重基本一致的兰州大尾羊和蒙古羊各18只,各随机选取9只进行断尾,‘兰州大尾羊’采用外科手术法,‘蒙古羊’采用橡圈结扎法。断尾羊为试验组,未断尾羊为对照组。屠宰后的结果显示:‘兰州大尾羊’和‘蒙古羊’试验组的采食量均低于对照组,而日增重、宰前活重和热胴体重则均是试验组比对照组高,但差异均不显著(P>0.05)。‘兰州大尾羊’对照组的尾臀部脂肪重和总脂肪重明显高于试验组,尾臀部脂肪重差异极显著(P<0.01),总脂肪重差异显著(P<0.05)。‘兰州大尾羊’其余各部位脂肪重均是对照组低于试验组。其中,皮下脂肪重和肾周脂肪重差异不显著(P>0.05);睾丸脂肪重、肠胃脂肪重和内部脂肪重呈现显著性差异(P<0.05)。‘蒙古羊’对照组的尾臀部脂肪重高于试验组,且差异性极显著(P<0.01)。皮下脂肪重、睾丸脂肪重、肾周脂肪重、肠胃脂肪重、内部脂肪重和总脂肪重在‘蒙古羊’的试验组和对照组之间没有显著性差异(P>0.05)。由分析可知,脂尾去除有提高兰州大尾羊和蒙古羊日增重及降低二者采食量的趋势;脂尾去除对‘蒙古羊’脂肪沉积分布影响不大,而‘兰州大尾羊’则有更多的脂肪沉积到了皮下、睾丸、肾周和肠胃周围,且断尾的‘兰州大尾羊’总脂肪重显著降低。

Comparison of Growth and Development Traits among Crossbreds of Dorset and Local Sheep Varieties in Gansu Province

In order to improve the meat production performance of local sheep varieties in Gansu Province, Dorset was introduced to crossbreed with the local sheep varieties, including Tan sheep, Small Tail Han sheep and Mongolia sheep. The offspring of different crossbreeding combinations were sampled randomly at different growth stages, and their growth and development traits were measured so as to screen out the best crossbreeding mode. The results showed that under the same crossbreeding mode, the growth rate of F3 was higher than that of F2, and of F2 was higher than that of F1. Among the F3 population, the growth rates of Dorset ×Han and Dorset × Mongolia hybrids were higher. Compared with those of Dorset ×Tan F3 hybrids, the body weights of male and female Dorset × Han and Dorset ×Mongolia F3 hybrids were increased by 5.59%, 4.40%, 5.93% and 3.76%, respectively. Among the F2 population, the growth rates of Dorset × Han and Dorset ×Mongolia hybrids were also higher. The body weights of male and female Dorset ×Han and Dorset × Mongolia F2 hybrids were higher than those of Dorset × Tan ×Han F2 hybrids by 5.99%, 3.67%, 9.80% and 5.00%, respectively. In the F1 population, the growth rates of Dorset × Han and Dorset × Mongolia hybrids were higher.Compared with those of Tan × Han F1 hybrids, the body weights of male and female Dorset × Han and Dorset × Mongolia F1 hybrids were increased by 11.32%,5.22%, 7.60% and 7.20%, respectively. Therefore, in the feeding area of Small Tai Han sheep, Mongolia sheep and Tan sheep, Dorset was the best sire for producing hybrid lambs. The economic benefit of crossbred offspring was obvious.

Analysis on Genetic Diversity and Isolation Mechanism by Distance of Different Ecological Type Sheep Breeds in Mon-golia Sheep Group

In the present study with Tan sheep, small-tailed Han sheep, Hu sheep, Tong sheep, and Wadi sheep, we detected the distribution of gene frequency of several microsatellite sites in different chromosomes, the result showed that： 1） Hu sheep was in the status of Hardy-Weinberg extreme disequilibrium （P 〈 0.01）, while populations including Tong sheep, small-tailed Han sheep, Tan sheep, and Wadi sheep were in Hardy-Weinberg equilibrium （P 〉 0.05）. 2） Variance analysis of the heterozygosity and poly- morphic information content at rnicrosatellite makers showed that there were not significant differences among populations as to heterozygosity and PIC （P 〉 0.05）, as to effective number of alleles there were not significant differences both among Tan sheep, Hu sheep, Tong sheep, and Wadi sheep, and between Wadi sheep and small-tailed sheep （P 〉 0.05）, but between the former three populations and the latter two populations, there were significant differences （0.01〈 P 〈0.05）. The variation levels of small-tailed Han sheep was the highest in the five populations based on microsatellite maker data, subsequently followed by Wadi sheep, Tong sheep, Tan sheep, and then Hu sheep. 3） The phylogenetic relationships of the five sheep populations in this study did not meet the mechanism of isolation by distance, and the genetic differentiation relationships among five sheep populations were not closely linearly correlative with their geography distribution. Our findings supported related records in literature： The five populations originated on different time stage from the primogenitor population and communicated genetically with each other thereafter in the process of natural and artificial selection and on different ecological environment.

Cloning of Hoxc8 Promoter in Mongolian Sheep by Thermal Asymmetric Interlaced PCR

[Objective] The research aimed toexplore the method to obtain Hoxc8 pro- moter of Mongolian Sheep. [Method] Thermal asymmetric interlaced PCR was used to amplify the promoter sequence of Hoxc8 inMongolian Sheep. [Result] The ob- tained sequence by usingthermal asymmetric interlaced PCRwas not ideal and the sequencing results were not matching to the known sequence. Though promoter se- quence of Hoxc8 in Mongolian Sheep was not obtained by thermal asymmetric in- terlaced PCR, but the results could provide references for the relevant studies in the future. [Conclusion] The research laid the foundation for further study on the methy- lation status Hoxc8 promoter in Mongolian Sheep.

Variation of Water-Use Efficiency of Leymus chinensis and Cleistogenes squarrosa in Different Plant Communities in Xilin River Basin, Nei Mongol

Water is usually considered to be a key limiting factor for the growth and reproduction of steppe plants in the Xilin River Basin, Nei Mongol. Foliar delta C-13 values, an indicator of long-term intercellular carbon dioxide concentration and thus of water-use efficiency (WUE) in plants, were measured on Leymus chinensis (Trin.) Tzvel. and Cleistogenes squarrosa (Trin.) Keng. in six communities of different habitats in die Xilin River Basin. The foliar delta C-13 values of both species tended to increase with decreasing soil water content (SWC) and a significant negative correlation was found between foliar delta C-13 Values and SWC in different soil layers, indicating that the two species could change WUE according to water availability. We also found relatively constant leaf water contents (LWC) of the two species in different habitats. Our results implied that the two steppe species might have adapted to different soil water regimes either through adjusting stomatal conductance to get a proper WUE, or through enhancing the osmosis-regulating ability to keep a relatively stable LWC. Our findings could partially explain why the two plant species have a wide distribution range and become dominant in the Xilin River Basin.

Cloning and Sequence Analysis of Genome from the Inner Mongolia Strain of the Endogenous Betaretroviruses (enJSRV)

In order to amplify the complete genome of enJSRV from the strain of Inner Mongolia (enJSRV-NM), we used enJSRV-specific and JSRV-specific DNA probes in dot blot hybridization. Seven pairs of primers were designed based on Genbank sequences. Seven fragments were obtained by PCR and were cloned into the PMD19-T vectors. The recombinant plasmids were sequenced and analyzed. The results showed that the genome was 7 942 bp in length and contained four overlapping open reading frames corresponding to the gag, pro, pol and env genes as well as an additional open reading frame (orf-x) that overlaps the 3' end of the pol gene. The nucleotide acid sequences of the enJSRV-NM loci were compared with the sequences of South Africa enJS56A1 strain (Accession No. AF153615) and USA JSRV21 strain (Accession No. AF105220). The nucleotide acid identities were 99.2% and 92.3% respectively. Two zinc fingers were found in the NC region in the predicted amino acid sequence. However, the YXXM motif, which is a reliable molecular marker for the infectious exogenous virus, was not found in the TM region. It was found that the enJSRV-NM region was 90%-98% identical at the amino acid level to its exogenous infectious counterparts in most of the retroviral genome. This is the first nucleotide sequence of enJSRV reported in P.R China. The resource work has provided a wide range of information useful not only for expression genomics and annotation of genomic DNA sequence, but also for further research on the clinical diagnosis of OPA.

Goyo cashmere company, Mongolia

In general the Goyo firm is one of best Cashmere Companies in Mongolia which is already exports their goods and services overseas in market throughout the world, which means it has international trade and finance. In this report it is discussed the Goyo Cashmere Company and the Cashmere industry in Mongolia. And it is recommended one new business idea which makes the Goyo Cashmere Company competitive in the market and gives some the new opportunities that no other Cashmere firm have. And more on it is discussed strategies entering the overseas market with its related risks and ways of reducing the risks. For conclusion the Goyo cashmere according to the new idea it can successful in the market.