鸭血红素加氧酶-1（HO-1）基因表达及对蛋壳颜色的影响

以35周龄产绿壳蛋巢湖鸭、产白壳蛋巢湖鸭以及樱桃谷鸭为素材,采集每只鸭的肝脏和输卵管子宫部,提取总RNA进行cDNA反转录,利用实时荧光定量PCR（real-time PCR）方法检测样品中血红素加氧酶（heme oxygen-ase,HO-1）基因的表达水平,分析不同品种、品系间及同一品种不同器官中HO-1mRNA的表达差异。结果显示：不同品种间,HO-1基因在肝脏组织中相对表达量无显著差异（P〉0.05）,在子宫组织中表达量巢湖鸭极显著高于樱桃谷鸭（P〈0.01）。不同品系间,HO-1基因在肝脏组织中相对表达量无显著性差异（P〉0.05）;巢湖鸭2个品系在子宫中的相对表达量差异不显著,但均显著高于樱桃谷鸭。在同一品种内,HO-1基因在肝脏组织中的相对表达量均极显著高于子宫组织（P〈0.01）。     

樱桃谷鸭、白羽番鸭和苏牧麻鸭生长性能、屠宰性能和常规肉品质比较分析

试验选择樱桃谷鸭、白羽番鸭和苏牧麻鸭作为研究材料,探讨3个鸭种1～10周龄生长性能和10周龄屠宰性能,分析其肉用性能.结果表明:①樱桃谷鸭和苏牧麻鸭前期生长快,白羽番鸭在6～8周龄达到增重高峰.②3个鸭种10周龄全净膛率和瘦肉率分别在70%和23.7%以上.樱桃谷鸭腹脂率、苏牧麻鸭瘦肉率,不同性别间差异显著(P<0.05),白羽番鸭所测全部指标中,公母均存在显著差异(P<0.05).③3个鸭种肉品质存在较大差异,但均未偏离正常值范围.     

鸭IFIT5基因(544G>A)多态性与部分免疫指标的关联分析

探索IFIT5基因作为抗性性状的候选标记的可能性,为家禽抗病育种提供一些参考依据。以樱桃谷北京鸭、苏牧麻鸭(樱桃谷鸭×金定鸭)、金定鸭、白羽番鸭为试验材料,利用DNA直接测序技术扫描IFIT5基因单核苷酸多态性(SNP),并分析其与部分免疫指标的关联性。结果表明:仅在IFIT5基因外显子2上检测到一个错义突变(G544A),产生2种等位基因,2种基因型(GG、GA),未发现有AA基因型。经χ2检验,4个鸭群体只有金定鸭和苏牧麻鸭处于Hardy-Weinberg平衡状态。关联分析结果显示:樱桃谷鸭体内H5含量GG型显著高于GA型(P0.05),而Ig M含量GG型显著低于GA型(P0.05),其余免疫指标均无显著差异(P0.05);苏牧麻鸭体内H5含量GG型极显著高于GA型(P0.01),其余免疫指标均无显著差异(P0.05);金定鸭不同基因型各免疫指标均无显著差异(P0.05)。白羽番鸭在+544位点均为GG纯合基因型。由此可以看出,IFIT5(544GA)可作为樱桃谷鸭体内H5含量的候选分子标记。     

三种肉鸭生长及屠宰性能比较研究

试验旨在研究3种肉鸭(樱桃谷鸭、广东肉麻鸭、重庆白鸭)的生长和屠宰性能,探索其适宜加工生产方式。设定相同的出栏体重(1.9 kg),测定3个肉鸭群体达到该体重时的用料情况及屠宰性能。结果表明:樱桃谷鸭29日龄达到出栏体重,广东肉麻鸭35日龄,重庆白鸭53日龄;樱桃谷鸭生长速度最快,相同周龄体重为樱桃谷鸭广东肉麻鸭重庆白鸭,且各肉鸭间差异显著(P0.05);饲料报酬为樱桃谷鸭广东肉麻鸭重庆白鸭;屠宰率、全净膛率广东肉麻鸭与重庆白鸭差异不显著(P0.05),均显著高于樱桃谷鸭(P0.05);腹脂率重庆白鸭显著高于樱桃谷鸭与广东肉麻鸭(P0.05)。综合3个肉鸭群体的生长及屠宰性能及产品特性,认为樱桃谷鸭适宜进行分割加工,广东肉麻鸭适宜以活禽形式销售,重庆白鸭适宜制作酱板鸭、卤鸭。     

不同配套系北京鸭的生产性能与血液生化指标特性研究

试验测定了Z型北京鸭、樱桃谷北京鸭(简称樱桃谷鸭)、法国克里莫北京鸭(简称奥白星鸭)的早期生长发育、饲料转化率、屠体性能和部分血液生化指标.结果Z型北京鸭、奥白星鸭、樱桃谷鸭7周龄的平均体重分别达到3662、3480、3344克,品系间差异极显著(P＜0.01).饲料转化率各组鸭无显著差异(P＞0.05).樱桃谷鸭的胸肉率显著高于奥白星鸭(P＜0.05),腿肉率显著高于Z型北京鸭和奥白星鸭(P＜0.05).根据北京鸭的生长曲线,商品肉鸭的生长期宜分为0～2、3～5和6～7周龄3个饲养阶段.     

拜城油鸡A-FABP、H-FABP和PPAR-PPAR-γ基因mRNA表达的发育性变化及其与肌内脂肪含量的相关性研究

采用实时荧光定量PCR技术,分别对3、7、12和16周龄拜城油鸡肌肉组织中脂肪细胞型脂肪酸结合蛋白(A-FABP)、心型脂肪酸结合蛋白(H-FABP)和过氧化物酶体增殖物激活受体(PPAR-γ)基因mRNA表达量进行分析,结合肌内脂肪(IMF)含量测定,分析H-FABP、A-FABP和PPAR-γmRNA表达的发育性变化及其与IMF的相关性。结果显示:拜城油鸡肌肉组织中A-FABP mRNA相对表达量随周龄的增长呈上升趋势,其中A-FABP基因在胸肌16周龄时的相对表达量显著高于3、7和12周龄(P0.05),该基因在12、16周龄时腿肌中的表达量显著高于3和7周龄(P0.05);H-FABP mRNA表达量随着拜城油鸡周龄增加呈现下降趋势,但各周龄间均不存在明显的发育性变化(P0.05);PPAR-γ基因在公鸡胸肌16周龄时的mRNA表达量最高,且显著高于3、7和12周龄(P0.05),公、母鸡腿肌PPAR-γmRNA表达量随着周龄呈逐渐上升趋势,在16周龄时的表达量最高,且显著高于3周龄(P0.05)。不同发育阶段拜城油鸡肌肉组织中A-FABP、H-FABP和PPAR-γmRNA表达量与其IMF含量呈不同程度的相关性,A-FABP mRNA表达量与其IMF含量呈现极显著的正相关(P0.01);H-FABP mRNA表达量与IMF含量存在负相关,但相关性均未达到显著水平(P0.05);PPAR-γmRNA表达量与IMF含量间存在正相关,但相关性均未达到显著水平(P0.05)。由此推测,A-FAPB基因对IMF的沉积具有调控作用,并可作为拜城油鸡IMF性状进行分子标记辅助选育的遗传标记之一。     

鸭多巴胺受体D1基因CDS区多态性与生长性状的关联性分析简

本研究采用PCR-SSCP法与DNA直接测序技术相结合对兴义鸭和樱桃谷鸭多巴胺受体D1 (dopamine receptor D1,DRD1)基因编码序列(coding sequence,CDS)区130－587 bp区域的多态性进行检测,并分析其多态性对樱桃谷鸭生长性状的影响。结果表明,在樱桃谷鸭和兴义鸭DRD1基因编码区130－587 bp区域内均检测到3种基因型：AA、BB和AB,2个等位基因：A和B;AA基因型均为优势基因型,频率分别为0.7416和0.5643,等位基因A均为优势等位基因,频率分别是0.8539和0.7204;多态信息含量分别为0.2184和0.3217,分别处于低度多态和中度多态位点,樱桃谷鸭群体中该座位基因型分布处于Hardy-Weinberg平衡（P>0.05）,兴义鸭群体则偏离了Hardy-Weinberg平衡（P<0.05）;序列比对发现2个SNPs位点,其中c.189 T＞C为同义突变,c.507 T＞A为错义突变,导致丝氨酸（S）变成精氨酸（R）。关联分析结果显示,BB基因型樱桃谷鸭个体的8周龄重和12周龄体斜长显著高于AB基因型（P<0.05）,10周龄重、12周龄重和12周龄胸深显著高于AA和AB基因型（P<0.05）。研究结果揭示该多态座位可能是影响鸭生长性状的一个标记辅助选择位点。     

Calpain 1．5 mRNA表达量与鸭肉嫩度关系的研究

选择60只70日龄左右、体重相似高邮鸭、樱桃谷鸭和番鸭,屠宰后取左半膛测定剪切力,用荧光实时定量PCR法,以β-actin基因为内标,检测calpain 1.5基因的表达量与嫩度的关系,并进行品种间比较.通过对3个品种鸭剪切力的测定.高邮鸭>樱桃谷鸭>番鸭,差异均不显著(P>0.05);3个品种都是胸肉<腿肉,即胸肉嫩度大于腿肉,差异显著(P<0.05).说明3个品种鸭肉嫩度由高到低依次为番鸭>樱桃谷鸭>高邮鸭.鸭胸肉与腿肉calpain 1.5基因mRNA表达量差异显著(P<0.05).肉的剪切力和calpain 1.5基因mRNA相对表达量呈对数关系(0.5相似文献   

三个肉鸭品种肉用性能的比较研究

选择健康、体重相近的7日龄骡鸭、樱桃谷鸭和麻鸭各30羽(公母各半)。每个品种鸭设3个重复,每个重复10羽鸭,各组环境条件和饲料均一致,试验鸭饲喂到56日龄时进行屠宰测定。结果表明:(1)樱桃谷鸭胸肌率比骡鸭和麻鸭高47.13%和60.11%(P0.01),而骡鸭腿肌率分别比樱桃谷鸭和麻鸭高47.07%和29.02%(P0.01);(2)骡鸭剪切力值比樱桃谷鸭和麻鸭分别高35.56%和22.14%,差异显著(P0.05);(3)骡鸭胸肌粗蛋白和粗脂肪分别比樱桃谷鸭、麻鸭低6.49%(P0.01)、3.88%(P0.05)和42.86%(P0.05)、5.88%(P0.05)。     

樱桃谷鸭MyOD1基因5′-UTR区域多态与生长和屠宰性状相关分析

为揭示樱桃谷鸭MyOD1基因5′-UTR区的多态性,本研究随机选取100只同日出雏、同等管理条件、健康无病的樱桃谷鸭(♂:55;♀:45)为实验材料,采用PCR-SSCP法结合直接测序技术,筛查MyOD1基因5′-UTR区的SNPs,分析其与鸭体生长和屠宰性状的关联性。结果表明:在5′-UTR区域筛查到了1个SNP位点g.95617 CG,形成了AA、AB和BB 3种基因型,其中AB基因型为优势基因型(P=0.5385),A等位基因为优势等位基因(P=0.587),多态信息含量(PIC)为0.367,属中度多态(0.25PIC0.5),卡方适合性检验结果表明(χ2=1.262),基因型分布未偏离Hardy-Weinberg平衡状态(P0.05),可能是经过长期的选育并使得该区域重新回到了平衡状态,一定程度上反映了樱桃谷鸭的高度选育现状;关联性分析结果证实,突变AA基因型鸭群体2、6、8周龄活重显著高于其他基因型群体(P0.05),AA型鸭个体屠宰率显著优于野生BB型个体,可能是g.95617 CG突变增强了鸭群体的肌肉沉积效率。以上结果表明,MyOD1基因5′-UTR区域对鸭的生长和屠宰性状有重要意义。     

Effect of DNA polymorphisms related to fatty acid composition in adipose tissue of Holstein cattle

Fatty acid composition of adipose tissue has been recognized as an important carcass trait because of its relationship with eating quality such as favorable beef flavor and tenderness. Therefore, we investigated the effects of genetic polymorphisms of liver X receptor, alpha (LXR), stearoyl‐CoA desaturase (SCD), Fatty acid synthase (FASN), and Fatty acid binding protein 4 (FABP4) on fatty acid composition in intramuscular fat tissue of Holstein steers. The major allele frequencies were 0.705 in SCD, 0.518 in FABP4, 0.888 in FASN, and 0.984 in LXR. Genotyping of SCD showed significant effect on C14:0, C14:1, C18:0 and saturated fatty acid (P < 0.05). In addition, the result suggested that SCD genotype possibly had effect on composition of C18:1 and monounsaturated fatty acid. Genotype of FABP4 had significant effect on composition of C16:0. Effect of LXR genotypes could not be analyze because of extremely biased genotype frequencies. Our results suggest that genotypes of SCD and FABP4 may in part affect meat quality in Holstein.     

High‐level exogenous trans10, cis12 conjugated linoleic acid plays an anti‐lipogenesis role in bovine mammary epithelial cells

Primary bovine mammary epithelial cells (BMECs) were treated by 0, 37.5, 75, 112.5, 150 μmol/L trans10, cis12 conjugated linoleic acid (CLA) to evaluate the effects of different level trans10, cis12 CLA on lipogenesis in BMEC. Addition of 75–150 μmol/L trans10, cis12 CLA reduced significantly the triacylglycerol (TAG) content (P < 0.05), but did not have inhibiting action on cell proliferation (P > 0.05). Treatment with 150 μmol/L trans10, cis12 CLA for 48 h resulted in a 17.1% reduction (P < 0.0001) of medium chain fatty acids (MCFA, C14 < C < C16), a 26.5% reduction (P < 0.0001) of unsaturated fatty acids (UFA) and a corresponding reduction of the mRNA abundance of acetyl coenzyme A (acetylCoA) carboxylase (ACC) (P = 0.046), fatty acid synthase (FAS) (P = 0.017) and stearoylCoA desaturase1 (SCD1) (P = 0.002). Another finding was that trans10, cis12 CLA elevated expression of diacylglycerol acyltransferase2 (DGAT2) (P = 0.020) and long chain acylCoA synthetases (ACSL) (P = 0.032). In conclusion, higher trans10, cis12 CLA, not low trans10, cis12 CLA, inhibited milk fat synthesis and changed fatty acid composition by regulating the expression of FAS, ACC, SCD1, DGAT2 and ACSL.     

Effects of dietary ramie level on growth performance,serum biochemical indices,and meat quality of Boer goats

This study was conducted to evaluate the use of ramie as forage on growth performance, serum biochemical indices, and meat quality of Boer goats. For this, 60 Boer lambs were divided into four groups fed the TMR with 0%, 10%, 20%, and 40% (control, and groups I, II, III, respectively) ramie. The experiment lasted for 90 days with a pretest for 15 days. Venous blood and longissimus dorsi (LD) muscle samples were collected after 24 h fasted at the end of the experiment. The results showed that ramie seems no significant changes in average daily gain (ADG) and other parameters for growth performance, only 40% ramie in TMR significantly reduced average daily feed intake (ADFI) (P < 0.05). Compared to the control, group II (20%) showed significant increases in total protein (TP) and globulin (GLB) levels, and decreases in albumin/globulin level (P < 0.05) in serum. Meanwhile, serum total cholesterol (TC) (P < 0.05) and free thyroxine (FT4) level were significantly reduced with up to 20% or more ramie in TMR. Moreover, the total amino acid and flavor amino acid levels in LD muscle were not affected by ramie. However, significant increases (P < 0.05) were observed in linoleic acid, polyunsaturated fatty acid, and polyunsaturated fatty acid/saturated fatty acid levels in group II. Overall, these results indicated that up to 20% ramie in TMR have no impairment in growth performance, health and meat quality, whereas high level ramie might have a negative effect on feed intake.

     

Effects of dietary corn oil and vitamin E supplementation on fatty acid profiles and expression of acetyl CoA carboxylase and stearoyl‐CoA desaturase gene in Hu sheep

This study was conducted to assess the effects of dietary corn oil and vitamin E supplementation on fatty acid (FA) profiles and abundances of acetyl‐CoA carboxylase (ACC) and Δ⁹ stearoyl‐CoA desaturase (SCD) mRNA of Hu sheep. Animals were allocated to three dietary treatments: basal and supplemented with 3% corn oil (CNO), or CNO plus 500 mg/kg vitamin E (COE). The experiment lasted for 10 weeks. No differences were observed in growth performance and carcass qualities among the three treatments (P > 0.05). Feeding CNO and COE diets increased polyunsaturated FAs including cis 9 trans 11 conjugated linoleic acid, and decreased saturated FA in longissimus muscle (P < 0.05). The mRNA abundances of ACC and SCD as detected by real‐time PCR were reduced (P < 0.05) in liver and subcutaneous fat by supplementary oil, while the SCD mRNA level in longissimus muscle was also reduced (P < 0.05). Inclusion of vitamin E did not have further effects on mRNA abundances of these two enzymes. It is suggested that dietary corn oil supplementation may reduce FA biosynthesis and influence FA profiles in Hu sheep through decreased expression of both ACC and SCD genes.     

Variations in genes involved in fat metabolism and their association with ultrasonic and carcass traits in Japanese Black steers

Polymorphisms in genes involved in lipid metabolism have been reported to be associated with fatty acid composition of adipose tissue. However, the relationship of these polymorphisms with premortem ultrasonic traits is unknown. The objective of this study, therefore, was to assess the association between polymorphisms in fatty acid synthase, stearoyl‐coenzyme A desaturase (SCD), sterol regulatory element‐binding protein 1 (SREBP1), diacylglycerol acyltransferase 1, and nuclear receptor subfamily 1, group H, number 3 genes with ultrasonic and carcass traits in Japanese Black steers (n = 300) under progeny testing at the Livestock Improvement Association of Miyazaki. To have a comprehensive analysis of the association between the aforementioned genetic polymorphisms and ultrasonic traits, longitudinal measurements of ultrasonic traits were taken. Furthermore, the association of these genetic polymorphisms and carcass traits was evaluated. The polymorphisms in the SCD gene and SREBP1 were associated (P < 0.05) with some ultrasonic traits at multiple stages. To add to that, the polymorphisms were associated (P < 0.05) with some carcass traits. These findings suggest that the polymorphisms in SCD and SREBP1 are functional mutations or could be related to mutations that can aid in selection to improve some ultrasonic and carcass traits.     

松辽黑猪、雷香猪、杜长大白猪肉质性状及肌肉营养成分比较研究

为了比较松辽黑猪、雷香猪、杜长大白猪肉质性状及肌肉营养成分，选取松辽黑猪、雷香猪、杜长大白猪进行屠宰，对肉质性状、肌肉氨基酸及脂肪酸含量进行测定，结果表明：松辽黑猪剪切力、肌内脂肪含量显著高于杜长大白猪（P<0.05），熟肉率显著高于雷香猪（P<0.05），雷香猪剪切力、肌内脂肪含量极显著高于杜长大白猪（P<0.01）；松辽黑猪和雷香猪肌肉中丙氨酸含量极显著高于杜长大白猪（P<0.01），甘氨酸含量松辽黑猪显著高于雷香猪（P<0.05），极显著高于杜长大白猪（P<0.01）；雷香猪亚油酸含量显著低于杜长大白猪（P<0.05）。文章对优质高端黑猪肉生产群体的选择提供了参考。     

Interactions of bovine oocytes with follicular elements with respect to lipid metabolism

Among many factors, lipid metabolism within the follicular environment emerges as an important indicator of oocyte quality. In the literature a crucial significance is described concerning follicular fluid (FF) composition as well as messenger RNA (mRNA) expression in follicular cells. The aim of this study was to describe the relationship between oocyte, FF and follicular cells with regard to lipid metabolism. The set of data originating from individual follicles comprised: lipid droplets (LD) number in oocytes (BODIPY staining), mRNA expression of seven genes in cumulus and granulosa cells (SCD, FADS2, ELOVL2, ELOVL5, GLUT1, GLUT3, GLUT8; real time polymerase chain reaction) and fatty acid (FA) composition in FF (gas chromatography). Obtained results demonstrate significant correlation between oocyte lipid droplets number and FA composition in FF. However, gene expression studies show significant correlation between LD number and GLUT1 gene only. Moreover, the present experiment revealed correlations between FA content in FF and expression of several genes (SCD, FADS2, ELOVL5, GLUT8) in granulosa cells, whereas only the SCD gene in cumulus cells. We suggest that the results of our experiment indicate the importance of glucose : lipid metabolism balance, which contributes to better understanding of energy metabolism conversion between oocytes and the maternal environment.     

Effects of growth rate on carcass and meat quality traits and their association with metabolism-related gene expression in finishing pigs

The objective of this study was to evaluate the effect of different growth rates on carcass characteristics and meat quality and their relationship with myogenesis and lipogenesis in finishing pigs. Pigs were slaughtered at the same age and were assigned to high (HGR) or low (LGR) growth rates with 120 kg or 110 kg final body weights at slaughter. The results indicated that pigs with HGR had heavier (P < 0.05) final body weight, carcass weight, dressing percentage, backfat thickness, higher (P < 0.05) concentrations of fat in the muscle and higher (P < 0.05) total RNA concentration in muscle than pigs with LGR. The messenger RNA (mRNA) expression of lipoprotein lipase, fatty acid synthase, malic enzyme, peroxisome proliferator-activated receptor γ, and sterol regulatory element binding protein-1 in fat were higher (P < 0.05) in pigs with HGR. Additionally, the mRNA expression of glycogen synthase in muscle was lower (P < 0.05) in pigs with HGR. These results indicate differences in postmortem myogenesis and lipogenesis traits of pigs with different growth rates; these differences in turn might have affected carcass characteristics and meat quality.     

Effects of nutritional level of concentrate‐based diets on meat quality and expression levels of genes related to meat quality in Hainan black goats

The present study investigated the effects of the nutritional levels of diets on meat quality and related gene expression in Hainan black goat. Twenty‐four goats were divided into six dietary treatments and were fed a concentrate‐based diet with two levels of crude protein (CP) (15% or 17%) and three levels of digestive energy (DE) (11.72, 12.55 or 13.39 MJ/kg DM) for 90 days. Goats fed the concentrate‐based diet with 17% CP had significantly (P < 0.05) higher average daily gains (ADG) and better feed conversion rates (FCR). The pH _24h value tended to decrease (P < 0.05) with increasing DE levels. The tenderness of Longissimus dorsi muscle (LD) and Semimembranosus muscle (SM) reduced with increasing CP levels (P < 0.05). With increasing DE levels, tenderness was increased (P < 0.05). The heart fatty acid‐binding protein (H‐FABP) mRNA expression levels in LD and SM increased with increasing DE levels (P < 0.05), but decreased with increasing CP levels (P < 0.05). The calpastatin (CAST) and μ‐calpain mRNA expressions levels in LD and SM were affected significantly (P < 0.05) by CP and DE levels in the diet. Therefore, the nutritional levels of diets affect meat quality and expression levels of genes associated with meat quality in Hainan black goats.     

Effects of apple pomace‐mixed silage on growth performance and meat quality in finishing pigs

We measured the growth performance and meat quality of 10 crossbred (Yorkshire × Duroc × Landrace) neutered male pigs to evaluate the effects of apple pomace‐mixed silage (APMS). The pigs were divided into two groups and were respectively fed the control feed and the AMPS ad libitum during the experiment. No difference was found in the finished body weight, average daily gain, carcass weight, back fat thickness or dressing ratio between the control and the AMPS treatments, but average dairy feed intake (dry matter) was significantly lower and feed efficiency was significantly higher using the APMS treatment (P < 0.05). With regard to meat quality, the APMS increased the moisture content but decreased the water holding capacity (P < 0.05) compared with the control treatment. Furthermore, the APMS affected the fatty acid composition of the back fat by increasing linoleic acid (C18:2n6), linolenic acid (C18:3) and arachidic acid (C20:0) levels, while decreasing palmitic acid (C16:0), palmitoleic acid (C16:1) and heptadecenoic acid (C17:1) levels, compared with the control treatment. These results indicate that feeding fermented apple pomace to finishing pigs increases the feed efficiency and affects the meat quality and fatty acid composition of back fat.