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<正> 繁殖性状是绵羊品种的重要经济性状之一。绵羊为温带地区的季节性发情畜种,引入四川副热带地区后,其繁殖特性的变化将会直接关系到四川新区绵羊引种试验的成败,经过连续四年的观察和测定,基本弄清了绵羊引入我省新区后的繁殖特性,为控制绵羊的繁殖,提高绵羊的繁殖效率,建立四川新区绵羊繁殖体系提供理论依据和技术措施。 相似文献
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绵羊繁殖率和生产力的高低直接影响着绵羊产业的规模化发展,因此必须采取相应技术手段提高绵羊繁殖率。通过应用繁殖技术可以更好地促进绵羊发情,提高绵羊的繁殖成功率等,从而更好地实现绵羊高效生产。本文就绵羊繁殖技术应用进行了分析,并提出了提高绵羊繁殖率的措施,旨在为羊产业的发展提供一定参考。 相似文献
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繁殖性状是绵羊的主要经济性状之一,一直以来受到国内外研究者的关注,关于提高绵羊繁殖力的研究报道已有很多。近年来,随着分子生物技术的兴起与迅速发展,结合繁殖技术,使得提高绵羊繁殖性能的研究已深入到分子水平,并取得一定成绩。从数量遗传学角度来讲,绵羊繁殖性状遗传力为0.125,属于低遗传力性状,通过传统选择方法获得遗传进展的 相似文献
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试验以促甲状腺激素受体(thyroid stimulating hormone receptor,TSHR)作为影响绵羊季节性繁殖的候选基因开展了多态性分析研究。结果在绵羊TSHR基因CDS区发现了一处c.31AG突变位点,该突变为错义突变(T315A)。该位点在不同繁殖特性(季节性繁殖和常年发情)绵羊群体的基因型和等位基因频率有着明显不同的分布趋势,GG基因型和G等位基因为常年发情的3个绵羊品种(多浪羊、小尾寒羊、湖羊)的优势基因型和优势等位基因;常年发情的3个绵羊群体和季节性繁殖的3个绵羊群体之间等位基因G/A比值存在显著性差异(P0.05)。研究结果表明该SNP位点上G等位基因与绵羊常年发情性状具有显著的相关性,该位点碱基突变可能导致TSHR构象改变,与TSH结合能力发生变化,进行影响到绵羊的季节性繁殖活动。 相似文献
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在绵羊养殖中,传染性疾病是制约绵羊养殖经济效益的主要因素.羊传染性疾病可影响绵羊的多个系统,根据病原的不同造成不同的器官出现不同的损伤.绵羊生殖系统传染性疾病是一类由病原微生物感染引起的,主要对绵羊的生殖道器官造成病变作用的一类疾病,可造成公羊不育、母羊不孕、妊娠母羊流产、产死胎等,从而导致绵羊繁殖失败或繁殖障碍,给绵... 相似文献
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De Vries F Hamann H Drögemüller C Andrzejewski M Ganter M Distl O 《DTW. Deutsche tier?rztliche Wochenschrift》2004,111(9):349-354
PrP polymorphisms influence the scrapie susceptiblility of sheep. The objective of this study was to analyse the association between performance traits and the PrP genotype in the sheep breeds German black-headed and German white-headed mutton, Bleu du Maine, German mutton merino, Leine, Texel and Suffolk from Lower Saxony and Westphalia. We analysed performance traits such as scores for muscle mass, type and wool quality and the calculated daily weight gain using linear animal models. In all seven breeds no statistically significant associations were found between performance traits and the occurrence of ARR alleles, and the ARR/ARR genotypes, respectively. All genotyped sheep of all breeds investigated showed significantly superior performance traits in comparison to the non-genotyped animals. 相似文献
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Peter T. Birteeb Sunday Olusola Peters Abdulmojeed Yakubu Matthew Adekunle Adeleke Michael Ohiokhuaobo Ozoje 《Tropical animal health and production》2012,45(1):267-274
The characterisation of the small ruminant populations in developing countries will play a major role in the maintenance of the genetic resources as the basis for future improvement in livestock production. The present study aimed at morphological characterisation of the two main breeds of sheep in Ghana by assessing variation within and between breed populations using principal component and discriminant analyses. The two breeds were the Sahel and the Djallonke sheep of both sexes and of two groups namely, young (1 year old, consisting of 74 animals) and mature sheep (≥2 years old, comprising 219 animals). The analysis of variance revealed significant (P?<?0.05) differences in the morphological traits of the Sahel and the Djallonke sheep breeds with higher values recorded for the former. Sexual dimorphism was in favour of male animals in all the morphological traits examined. Mature animals also had comparative advantage over the young. Two principal components were extracted to discern the structure of the two genetic groups. The most discriminating traits between the two sheep breeds were rump height, height at withers, neck girth and pin-bone width. Mahalanobis distance between the two genetic groups was 5.723 (P?<?0.0001). The developed discriminant functions clearly discriminated and classified the Sahel and the Djallonke sheep into their breeds of origin, thus yielding 100, 93.4 and 90.4 % accurate classification for the rams, ewes and the overall sheep population, respectively. The present approach would greatly help in establishing management and conservation policies for the sustainable production of the two Ghanaian sheep breeds. 相似文献
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R Abdoli P Zamani SZ Mirhoseini N Ghavi Hossein‐Zadeh S Nadri 《Reproduction in domestic animals》2016,51(5):631-637
Ovulation rate and litter size are important reproduction traits in sheep and are of high economic value. Reproduction traits typically have low to medium heritabilities and do not exhibit a noticeable response to phenotypic selection. Therefore, inclusion of genetic information of the genes associated with reproductive ability could efficiently enhance the selection response. The most important major genes affecting prolificacy and their genetic diversities in different sheep breeds were reviewed. Different causative mutations with major effects on reproductive traits including ovulation rate and litter size have been found in various sheep breeds around the world. A general overview of the studies on main prolificacy genes showed that some alleles may express different phenotypic effects in different breeds, and thus, further studies on epistatic effects are necessary for more understanding of genetic control of reproductivity in sheep. Regarding the polygenic control of fertility traits, application of new high‐throughput technologies to find new variants is essential for future studies. Moreover, genomewide association studies and genomic best linear unbiased predictions of breeding values are likely to be effective tools for genetic improvement of sheep reproductive performance traits. 相似文献
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本研究旨在探讨甘南藏系绵羊(欧拉羊、甘加羊和乔科羊)及滩羊DGAT1基因16-17外显子多态性,为开展藏系绵羊遗传分化、藏系绵羊与其他绵羊的亲缘关系、藏系绵羊DGAT1基因与肉质性状关联等方面的研究提供参考.采用PCR-RFLP方法,检测501只绵羊DGAT1基因16-17外显子SNP,并对主要遗传参数进行统计学分析.结果表明:①藏系绵羊DGAT1基因16-17外显子均具有Alu Ⅰ酶切多态性,存在TT、TC、CC 3种基因型,其中CC基因型频率最高,为优势基因型;C等位基因频率高于T等位基因频率,为优势等位基因.②欧拉羊在DGAT1基因16-17外显子处于Hardy-Weinberg平衡状态(P＞0.05),而甘加羊、乔科羊在DGAT1基因16-17外显子处于Hardy-Weinberg不平衡状态(0.01＜P＜0.05).③独立性检验结果表明:各藏系绵羊间基因型分布差异不显著(P＞0.05),而滩羊与乔科羊之间差异极显著(P＜0.01),滩羊与欧拉羊、滩羊与甘加羊之间差异显著(0.01＜P＜0.05).④藏系绵羊在DGAT1基因16-17外显子Alu Ⅰ酶切位点均表现为中度多态.结果提示:在DGAT1基因16-17外显子Alu Ⅰ酶切位点上藏系绵羊之间基因型分布差异不显著(P＞0.05),而滩羊和藏系绵羊差异显著(0.01＜P＜0.05)、亲缘关系较远. 相似文献
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试验旨在研究Lpin2基因遗传变异对绵羊尾型和屠宰性状的影响。以两品种脂尾型绵羊广灵大尾羊和小尾寒羊为研究对象,采用DNA直接测序法检测Lpin2基因5'非编码区部分序列的单核苷酸多态性（SNPs）,并分析其与尾型及屠宰性状的关联性。结果发现,Lpin2基因5'非编码区起始密码子上游约1 200 bp的DNA序列中存在3个SNPs,即NC_019480.2:g.－663 dup ATT（SNP1）、g.－388 T > C（SNP2）和g.－330 T > G（SNP3）,其中SNP1为三核苷酸ATT重复扩展短串联重复序列（STR）的拷贝数变异（CNV）,在广灵大尾羊中的突变频率显著高于小尾寒羊（P<0.05）,显著降低了广灵大尾羊的胴体重与屠宰率（P<0.05）,对小尾寒羊的屠宰性状无显著影响（P>0.05）。SNP2和SNP3构成单倍型块,形成的单倍型对各性状无显著影响（P>0.05）。试验结果可为绵羊肉质性状的标记辅助选择提供参考依据。 相似文献
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JIAO Xiao-li JING Jiong-jie QIAO Li-ying HONG Zhong-shan LI Liu-an TIAN Chuan-yao KANG Cui-cui CHEN Ming-ming LIU Wen-zhong 《中国畜牧兽医》2017,44(4):1037-1045
This study was aimed to explore the effects of genetic variations of Lpin2 gene on tail type and slaughter traits in sheep. Two breeds of fat-tailed sheep such as Guangling Large Tailed sheep and Small Tailed Han sheep were chosen to identify the single nucleotide polymorphisms (SNPs) in 5' non-coding region of Lpin2 gene by using direct DNA sequencing, and the associations between SNPs and tail type and slaughter traits were analyzed. The results showed that three novel SNPs were found in 5' non-coding region about 1 200 bp upstream sequence from start codon ATG in Lpin2 gene, namely NC_019480.2: g.－663 dup ATT (SNP1), g.－388 T > C (SNP2) and g.－330 T > G (SNP3), sequencing data revealed that the trinucleotide ATT repeat expansion at SNP1 was cope number variation (CNV) of short tandem repeats (STR), the mutation frequency was significant higher in Guangling Large Tailed sheep than that in Small Tailed Han sheep (P<0.05), and caused the significant decreasing in carcass weight and dressing percentage in Guangling Large Tailed sheep (P<0.05), however this variation exhibited non-significant effects on the slaughter traits in Small Tailed Han sheep (P>0.05). SNP2 and SNP3 could be constructed into a haplotype block while the haplotypes didn't significantly affect the examined traits in two sheep breeds. This finding would provide references for marker assisted selection of the sheep meat quality traits. 相似文献
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本研究以卷曲相关同源蛋白（FRZB）基因作为候选基因,以同羊、小尾寒羊、兰州大尾羊和湖羊4个品种共计582只绵羊个体为试验材料,利用琼脂糖凝胶电泳结合DNA测序技术对FRZB基因的InDel进行筛查,旨在寻找与4个品种绵羊生长性状相关的InDel位点。结果表明,绵羊FRZB基因第1内含子上检测到一段14 bp的InDel突变;FRZB基因内含子区InDel突变位点在同羊、小尾寒羊、兰州大尾羊和湖羊群体中均存在II、ID、DD 3种基因型;关联分析表明,FRZB基因中检测到的InDel突变对同羊生长性状有显著影响（P<0.05）,其中II基因型的体长、背高、荐高、距骨宽度、尾长和尾宽在同羊群体中显著优于DD基因型,可以作为候选分子标记用于同羊分子标记辅助选择。这些结果提示,绵羊FRZB基因第1内含子上一个14 bp的插入突变可显著影响同羊生长性状,可以作为绵羊育种中生长性状的潜在分子标记。 相似文献
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Maryam Nosrati Hojjat Asadollahpour Nanaei Zeinab Amiri Ghanatsaman Ali Esmailizadeh 《Reproduction in domestic animals》2019,54(2):358-364
Ovulation rate and prolificacy are the most important reproductive traits that have major impact on the efficiency of lamb meat production. Here, we compared the whole genomes of the Romanov sheep, known as one of the high prolific breeds, and four other sheep breeds namely Assaf, Awassi, Cambridge and British du cher, to identify genetic mechanisms underlying prolificacy in sheep. Selection signature analysis revealed 637 and 477 protein‐coding genes under positive selection from FST and nucleotide diversity (Pi) statistics, respectively. Further analysis showed that several candidate genes including LEPR, PDGFRL and KLF5 genes are involved in sheep prolificacy. The identified candidate genes in the selected regions are novel and provide new insights into the genetic mechanisms underlying prolificacy in sheep and can be useful in sheep breeding programmes to develop improved breeds for high reproductive efficiency. 相似文献