5号染色体两候选SNP基因定位以及与绵羊臀尾性状的关联分析

脂尾(臀)性状是绵羊逆境生存的耐逆性状,其臀尾部大量储积脂肪的基因组变异研究目前仍是空白。本研究以国外新近报道的5号染色体上存在的可能与尾脂性状相关联的两处SNP为研究对象,分别采用PCR-RFLP和PCR-SSCP的方法检测两SNP在我国尾型极端差异的阿勒泰羊、湖羊、细毛羊以及藏羊群体中的多态性、基因型与等位基因分布,验证两SNP是否可作为我国低脂绵羊新品种培育的分子标记。研究结果表明:两SNP在我国脂尾(臀)型阿勒泰羊、湖羊与瘦尾型中国美利奴羊细毛羊和藏羊群体中高度分化,两SNP的T等基因与A等位基因在瘦尾型绵羊品种中高频出现,存在与瘦尾性状密切相关的趋势,提示此两个SNP可作为选育低脂绵羊新品种的有效分子标记。     

豫西脂尾羊微卫星DNA多态性研究

为了分析5个微卫星位点BL1038、BM757、BM4621、OarFCB304、OarFCB48在豫西脂尾羊群体中的多态性,试验采用非变性聚丙烯酰胺凝胶电泳方法检测其多态性。结果表明:在豫西脂尾羊群体中共发现5个微卫星位点有60个等位基因,有效等位基因(Ne)在6.010 3～10.846 8之间,平均Ne为8.430 3,OarFCB48的Ne最高为10.846 8;5个微卫星位点的平均杂合度(H)为0.876 7,OarF-CB48的H最高为0.907 8。微卫星位点OarFCB48的多态信息含量(PIC)最高为0.902 1,BM757的PIC最低为0.817 5,平均PIC为0.866 5。说明豫西脂尾羊群体属于PIC较高的遗传群体。     

阿勒泰羊Myf 5基因多态性与早期生长发育性状的相关性分析

采用PCR测序方法研究了152只阿勒泰羊群体Myf5基因多态性及其与群体生长发育性状的相关性。结果表明：在阿勒泰羊Myf5基因中存在3个多态位点,即位于Myf5基因第1外显子区域的19-CCT Ins/Del、第4外显子区域的C-109G以及C-383T;在这些位点均存在3种基因型。多态位点与体重和日增重的相关性分析表明,仅SNP位点C-383T与体重和平均日增重具有相关性（P〈0.05）,不同基因型体重和日增重排序为TT〈CT〈CC。说明Myf5基因该位点可能是影响阿勒泰羊生长发育性状的主效QTL或与之紧密连锁,可作为阿勒泰羊肥羔生产的候选分子标记。     

绵羊Fsp27基因组织表达、多态性及其与不同绵羊品种尾脂沉积能力的关联性分析

旨在研究绵羊Fsp27基因的组织表达/多态性及其与不同绵羊品种尾脂沉积能力的关联性。本研究采用qRT-PCR检测了营养充足期阿勒泰羊不同组织中Fsp27基因的表达情况,同时对营养充足期和营养匮乏期阿勒泰羊尾脂组织中Fsp27基因的表达情况进行了定量分析,采用PCR-SSCP结合测序技术检测了5个不同尾脂沉积能力绵羊品种Fsp27基因的突变情况,并分析了相关突变与绵羊尾脂沉积能力的关联性。结果表明,Fsp27基因在营养充足期阿勒泰羊尾脂中高表达,其表达量极显著高于其他组织（P<0.01）,在肾周脂肪和皮下脂肪组织中的表达量也较高,极显著高于心、肝、脾、肺、肾、胃、肠、皮肤和骨骼肌组织（P<0.01）。在心、肝、脾、肺、肾、胃、肠、皮肤和骨骼肌组织中呈微量表达,且各组织间差异不显著（P>0.05）。另外,营养充足期阿勒泰羊尾脂中Fsp27基因的表达量极显著高于营养匮乏期（P<0.01）。绵羊Fsp27基因在不同尾脂沉积能力品种群体中共检测到25个突变位点,其中位于第3外显子g.16771741的G/A突变以及第5外显子g.16774969的C/T突变均为错义突变,且与绵羊尾脂沉积能力高度相关。g.16771741的G/A突变在尾脂沉积能力较强的阿勒泰羊、小尾寒羊和湖羊群体中以G等位基因为主,分别占到86.8%、83.7%和85.7%,而尾脂沉积能力较差的中国美利奴细毛羊和萨福克羊群体中G等位基因分别仅占30.3%和11.1%。g.16774969的C/T突变在阿勒泰羊群体中以T等位基因为主,TT基因型占84.7%,CT基因型占15.3%,没有检测到CC基因型;在短脂尾型的小尾寒羊和湖羊群体中,TT和CT基因型也分别占到65.9%、50.4%和22.7%、41.1%,而在长瘦尾的中国美利奴细毛羊和萨福克羊群体中则以CC基因型为主,分别占到97.4%和69.4%,没有检测到TT基因型。以上研究结果表明,Fsp27基因在阿勒泰羊尾脂中高表达,且其在尾脂中的表达量与阿勒泰羊的营养状态密切相关,Fsp27基因第3外显子g.16771741的G/A突变以及第5外显子g.16774969的C/T突变与绵羊尾脂沉积能力高度相关,可以作为理想的分子标记用于低脂肪绵羊品种的选育。     

豫西脂尾羊血液蛋白的多态性研究

本研究利用聚丙烯酰胺凝胶电泳技术(PAGE)分析了河南豫西脂尾羊的血红蛋白(Hb)、转铁蛋白(Tf)、红细胞蛋白质(Ep)、前白蛋白(Pa)和血清酯酶(Es)的多态性。结果表明,在豫西脂尾羊群体中Hb存在3种基因型为HbAA、HbAB、HbBB,它们受Hb^A和Hb^B两个共显性等位基因控制,其中HbAA基因型频率为0.0571,HbAB为0.6286,HbBB为0.3143;Hb^A等位基因频率为0.3714,Hb^B为0.6286。Tf存在3种基因型为TfAA、TfAB、TfBB,它们受Tf^A和Tf^B两个共显性等位基因控制,其中TfAA基因型频率为0.2000,TfAB为0.2545,TfBB为0.5455;Tf^A等位基因频率为0.3273,Tf^B为0.6727。Ep有EpAA和EpAa共2种基因型,其中EpAA基因型频率为 0.4286,EpAa为0.5714;Ep^A基因频率为 0.7143,Ep^a为0.2857。Es基因座有2个等位基因即Es⁺和Es^-,而且Es⁺和Es^-的基因频率分别为0.5500和0.4500,有3种基因型Es⁺⁺、Es^+-、Es^--的频率分别为0.4250、0.2500和0.3250。Pa上未检测到多态性,它呈现单态。     

小尾寒羊改良豫西脂尾羊试验报告

本试验让豫西脂尾羊与体型大、生长速度快、繁殖率高的小尾寒羊杂交,同时保留其产肉率高、爬坡能力强的优良特性。从而改进其总体生产性能。结果表明,杂交后代既继承了小尾寒羊的优良特性,又继承了脂尾羊的优良特性,该杂交模式值得大面积推广。     

小尾寒羊改良豫西脂尾羊杂交一代效果研究

偃师市利用小尾寒羊必廊豫西脂尾羊，其杂交一代与豫西脂尾羊相比，具有明显的改良效果。在相同的饲养管理条件下，公母羔初生重分别增加1．0kg和0．3kg，1月龄体重分别增加2．4kg和0．2kg和1．2kg,3月龄体重分别增加3．8kg和5．8kg，6月龄体重分别增加9.8kg和9.0kg;1岁羊体重增加11.2kg,1.5岁羊体重增加15.0kg；屠宰率增加2个百分点；产毛量年均增加1.3kg;繁殖率提高75.5个百分点.     

策勒黑羊母羊脂尾性状特征及其与体重、体尺的相关性分析

为了探究策勒黑羊脂尾性状特征及其与体重、体尺的相关性,试验选取健康的成年策勒黑羊母羊408只,测定体重(y)、体高(x₁)、体长(x₂)、体斜长(x₃)、胸宽(x₄)、胸深(x₅)、胸围(x₆)、管围(x₇)、尾长(x₈)、尾宽(x₉)和尾周长(x₁₀),计算尾体积(x₁₁),分析策勒黑羊母羊的尾体积差异,根据尾体积进行尾型分型,并对体重与脂尾性状和体尺指标进行相关性分析,构建体重的最优回归方程。结果表明：策勒黑羊母羊平均尾体积较大,为(18 108.51±11 868.52)cm³,策勒黑羊母羊的尾型分为小尾型、中尾型、大尾型和肥尾型;肥尾型策勒黑羊母羊的数量比较少(9只),中尾型数量较多(223只);肥尾型的策勒黑羊母羊的体重、体长、体斜长、胸围、尾长、尾宽和尾周长均极显著大于其他三种尾型(P<0.01);策勒黑羊母...     

本地脂尾绵羊膘情评定及其分级标准的研究

抓膘保膘是本地脂尾绵羊生产的重要环节.通过观察体躯丰满程度、被毛光泽与否、骨突显现程度,触摸腰椎横突问肌肉脂肪填充程度和脂尾大小与结实程度,把膘情分成3类10成6个等级,分类管理,是养好羊的重要措施.     

蒙古羊的起源及尾脂沉积的研究进展

蒙古羊是中国数量最多、分布最广的粗毛绵羊品种,其体质结实,适应性强,能耐受极粗放的饲养管理条件。蒙古羊尾部较强的脂肪沉积能力使其具有很好的抗逆性,但尾部脂肪沉积过多又不足以满足消费者对高品质羊肉的需求。结合现有的资料和研究成果,围绕蒙古羊的起源和尾脂沉积调控机制进行了总结,旨在为深入了解蒙古羊的起源和明确育种目标提供参考。     

Relationship between leptin content, metabolic hormones and fat deposition in three beef cattle breeds

The aim of the study was to determine if cattle breeds differing in their carcass characteristics also differ in the profiles of their leptin and metabolic hormones. Three breeds, Belgian Blue (BB) (n = 12), Limousin (L) (n = 12) and Aberdeen Angus (AA) (n = 12) with varying ability to deposit fat and protein were compared. Blood, muscle and subcutaneous (SC) adipose tissue were sampled. Animal performance, carcass and meat characteristics were determined as well as plasma leptin concentration, leptin gene expression in SC adipose tissue, leptin-receptor gene expression in SC adipose tissue and plasma concentration of insulin, tri-iodothyronin (T3), thyroxin (T4) and cortisol. The BB bulls showed the lowest values of leptin gene expression (P < 0.05). Values of plasma leptin concentration and of leptin-receptor gene expression tended to be lower in BB than in the other breeds. For a similar amount of adipose tissue (after normalisation), BB bulls showed a higher ratio of plasma leptin (P < 0.05), whereas normalised leptin gene and leptin-receptor gene expressions did not significantly differ between breeds. Belgian Blue bulls also differed in their metabolic hormone profile, tending to show lower values of insulin, T3 and T4 than the two other breeds. Cortisol levels were significantly lower (P < 0.05) in BB than in L and AA animals.     

Relationship of plasma lipid concentrations to fat deposition in pigs

The time course for changes in plasma free fatty acid and triglyceride concentration after removal of feed was established. Genetically obese and lean lines of pigs, two types of crossbred female pigs and a group of male pigs were used to establish the relationship between circulating free fatty acid or triglyceride concentrations and adiposity. Pigs were weighed, ultrasonically probed for backfat thickness, bled in a fed state and again in the fasted state. Plasma was analyzed for free fatty acid and triglyceride concentration. Fasting increased plasma free fatty acid, but only slightly increased triglyceride concentrations. There were several significant correlations between backfat thickness and plasma lipid concentrations; however, the low magnitude and inconsistency of these correlations precludes use of plasma lipid concentrations as indicators of adiposity in swine. Fasted obese pigs had lower plasma fatty acid concentrations than lean pigs at 2, 4 and 6 mo of age. If these plasma levels represent in vivo mobilization of fat, the results probably contrast with previously reported in vitro results wherein adipose tissue from obese pigs had lipolytic rates expressed on a cellular basis that were equal to or greater than those form lean pigs.     

Dietary conjugated linoleic acids increase intramuscular fat deposition and decrease subcutaneous fat deposition in Yellow Breed × Simmental cattle

This study was conducted to estimate the effect of dietary conjugated linoleic acids (CLA) on intramuscular and subcutaneous fat deposition in Yellow Breed × Simmental cattle. The experiment was conducted for 60 days. The results showed that the average backfat thickness, (testicles + kidney + pelvic) fat percentage and subcutaneous fat percentage in dietary CLA were significantly lower than in the control group, while intramuscular the fat percentage was significantly higher. Compared to the control group, the Longissimus muscle enzyme activities of lipoprotein lipase (LPL), fatty acid synthase (FAS) and acetyl‐coenzyme A carboxylase (ACC) in dietary CLA and the subcutaneous fat enzyme activities of LPL, hormone‐sensitive lipase (HSL) and carnitine palmitoyltransferase‐1 (CPT‐1) were significantly increased. Similarly, compared to the control group, the Longissimus muscle sterol regulatory element binding protein 1 (SREBP‐1), FAS, stearoyl‐coenzyme A desaturase (SCD), ACC, peroxisome proliferator‐activated receptor γ (PPARγ), heart fatty‐acid binding protein (H‐FABP) and LPL gene expression in dietary CLA were significant increased, as were the subcutaneous fat of PPARγ, H‐FABP, LPL, CPT‐1 and HSL in dietary CLA. These results indicated that dietary CLA increases IMF deposition mainly by the up‐regulation of lipogenic gene expression, while decreasing subcutaneous fat deposition mainly by the up‐regulation of lipolytic gene expression.     

Effect of colostral fat level on fat deposition and plasma metabolites in the newborn pig

The effects of colostral fat level on fat deposition and plasma concentrations of glucose, insulin, and free fatty acids (FFA) were determined in 28 newborn pigs during the first postnatal day. Soon after birth, pigs were allotted to four treatments groups. Group 1 was killed at birth. The remaining pigs were fed intragastrically sow colostrum that contained high (10.2%; HFC), normal (4.8%; NFC) or low (1.0%; LFC) levels of total fat at the rate of 15 to 18 g/kg birth weight at 65- to 70-min intervals. A total of 21 feedings was provided and pigs were killed 1 h after the last feeding. Body fat deposition increased linearly (P less than .01) with the amount of ingested fat by .32 (+/- .04) g per 1-g increase in fat intake. Fatty acid composition of the pigs changed toward that of the colostrum with increased fat in colostrum. More liver glycogen was lost (P less than .01) in pigs given LFC. Plasma concentrations of glucose and insulin were similar in pigs fed HFC and NFC. After the 11th feeding (14 h postnatal), LFC resulted in lower plasma glucose concentrations (P less than .05) than HFC or NFC. Plasma insulin concentrations also were lower in pigs fed LFC. Plasma FFA concentrations remained unchanged in pigs fed LFC but increased with both fat content in colostrum (P less than .05) and time (P less than .05) in the other two groups. Colostral fat plays a major role in the supply of energy and in glucose homeostasis in the neonatal pig.     

Genome‐wide association studies revealed candidate genes for tail fat deposition and body size in the Hulun Buir sheep

Fat‐tailed sheep have a unique characteristic of depositing fat in their tails. In the present study, we conducted genome‐wide association studies (GWAS) on traits related to tail fat deposition and body size in the Hulun Buir sheep. A total number of 300 individuals belonging to two fat‐tailed lines of the Hulun Buir sheep breed genotyped with the Ovine Infinium HD SNP BeadChip were included in the current study. Two mixed models, one for continuous and one for binary phenotypic traits, were employed to analyse ten traits, that is, body length (BL), body height (BH), chest girth (CG), tail length (TL), tail width (TW), tail circumference (TC), carcass weight (CW), tail fat weight (TF), ratio of CW to TF (RCT) and tail type (TT). We identified 7, 6, 7, 2, 10 and 1 SNPs significantly associated with traits TF, CW, RCT, TW, TT and CG, respectively. Their associated genomic regions harboured 42 positional candidate genes. Out of them, 13 candidate genes including SMURF2, FBF1, DTNBP1, SETD7 and RBM11 have been associated with fat metabolism in sheep. The RBM11 gene has already been identified in a previous study on signatures of selection in this specific sheep population. Two more genes, that is, SMARCA5 and GAB1 were associated with body size in sheep. The present study has identified candidate genes that might be implicated in tail fat deposition and body size in sheep.     

快速与慢速肉鸡脂肪生长与肌苷酸含量比较

本试验旨在相同条件下,比不同品种和性别肉鸡的脂肪生长量和肌苷酸含量及其相互关系。比较发现:(1)快速与慢速肉鸡的各项脂肪指标均无显著差异(p>0.05),但慢速鸡的肌肉脂肪、皮下脂肪和腹脂率分别比快速鸡高7%、13%和37%;(2)慢速肉鸡肌苷酸含量比快速高50%,且差异显著(p<0.05);(3)母鸡皮下脂肪(p<0.01)和腹脂率(p<0.05)显著高于公鸡,母鸡肌间和肌肉脂肪也分别高于公鸡6%和12%(p>0.05);(4)肌苷酸与腹脂率存在显著正相关(r=0.61,p<0.05)。     

藏猪和大约克猪ACADM基因表达量与脂肪沉积性状的相关性分析

为探究中链酰基辅酶A脱氢酶(ACADM)基因在不同品种猪组织中的表达水平,并分析其与猪脂肪沉积性状的相关性,采用Sange测序法对藏猪(58头)和大约克猪(60头)ACADM基因起始密码子上游1 kb区域进行了单核苷酸多态性(SNPs)筛选与基因分型,选取180日龄藏猪和大约克猪各10头屠宰后分别采集肝脏、背脂、心脏和...     

细胞因子对小尾寒羊胎盘成熟的影响

为了研究细胞因子对小尾寒羊胎盘成熟的影响 ,本实验采用液相竞争法和平衡法 ,对小尾寒羊空怀期 (n=5 )和妊娠期 (n=13)第 85天、10 5天、12 5天、14 0天和 15 0天 (足月 )时的血清白细胞介素 - 1β(IL - 1β)、白细胞介素 - 6 (IL - 6 )和肿瘤坏死因子(TNF)的含量分别进行检测。结果表明 ,IL - 1β和 IL - 6含量在 12 5天时与对照组间差异极显著 (P<0 .0 1) ,TNF含量在各时期与对照组差异均显著 (P<0 .0 1或 P<0 .0 5 )。随着妊娠过程的进展 ,三种细胞因子含量逐渐增加 ,12 5天时达到最高值 ,分别为 0 .390± 0 .196 ng/ ml,5 79.8± 15 2 .8pg/ ml和 2 .348± 0 .396 ng/ ml。而后逐渐下降 ,到足月前略有回升 ,但仍低于 12 5天时的最高值。由此看出小尾寒羊在妊娠期间 ,细胞因子与妊娠之间有着密切的关系 ,前者对于维持妊娠起到重要作用。由于 14 0天至足月3种细胞因子基本稳定 ,这表明胎盘于 14 0天左右达到成熟 ,IL- 1β和 IL- 6与启动分娩有关 ,而 TNF可能参与小尾寒羊分娩的启动。     

共轭亚油酸对猪脂肪沉积的影响

本文就共轭亚油酸对猪脂肪沉积、脂肪组织中脂肪酸的组成、脂肪代谢的影响作一综述,并探讨共轭亚油酸可能的作用机理。