首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
Leptin signalling plays a fundamental role in growth, fatness and body composition. The aim of this study was to investigate the porcine LEP gene sequence in an Iberian × Landrace experimental cross to identify polymorphisms associated with productivity and quality traits. Because of the documented effects on these traits of the LEPR c.1987C>T polymorphism, the LEP and LEPR c.1987C>T polymorphisms and their interactions have been jointly investigated. The LEP gene sequencing has allowed the identification of 39 polymorphisms, eight of which are novel. Three intronic SNPs, LEP g.1382C>T, LEP g.1387C>T and LEP g.1723A>G, have been genotyped, and association analyses have been carried out. Analyses of LEP g.1387C>T, fully linked to LEP g.1382C>T, have revealed additive effects on live and carcass weights and dominant effects on several backfat thickness measurements. Novel effects of both LEP and LEPR polymorphisms on fatty acid composition in subcutaneous fat have been detected, probably mediated through the effects on fatness. The results reported here suggest that the T alleles of both LEP g.1387C>T and LEPR c.1987C>T, which are fixed in the Iberian pigs, would lead to an increase in growth, fatness and saturated fatty acid content in fat, which could be explained by an increased feed intake.  相似文献   

2.
The objective of this study was to correlate the expression pattern of candidate genes with the intramuscular fat (IMF) content and fatty acid composition of the Longissimus dorsi muscle of Duroc × Shanzhu commercial crossbred pigs. Animals of both sexes were slaughtered at a body weight of about 90 kg. The IMF content and fatty acid composition of the Longissimus dorsi muscle were measured and correlated with candidate genes mRNA expression (AdPLA, ADRB3, LEPR, MC4R, PPARγ, PPARα, LPL, PEPCK, and SCD). Females presented higher IMF content (p < 0.05) than males. The total saturated fatty acid (SFA) in males was greater (p < 0.01), whereas the total monounsaturated fatty acid (MUFA) (p < 0.01) and polyunsaturated fatty acid (PUFA) (p < 0.05) were lower than in females. The expressions of AdPLA, MC4R, PEPCK, and SCD correlated with the IMF content (p < 0.05). AdPLA showed a positive association with MUFA and a negative association with SFA (p < 0.05). LEPR and MC4R were both positively and significantly associated with C18:3 and C20:0 (p < 0.05). PPARα and PPARγ were negatively correlated with SFA, and PPARγ was positively associated with MUFA (p < 0.05). LPL was positively associated with MUFA and negatively associated with SFA (p < 0.05). PEPCK was negatively correlated with PUFA (p < 0.05). SCD was positively associated with MUFA (p < 0.05). The revealed correlations may confirm that these candidate genes are important for fat deposition and fatty acid composition in pigs, and the evaluation and use of these genes may be useful for improving porcine meat quality.  相似文献   

3.
This study aimed to evaluate the effects of single nucleotide polymorphisms (SNPs) in candidate genes for meat quality using a custom 96‐SNP panel (Illumina Vera Code GoldenGate Assay) on 15 traits collected from 400 commercial pigs. Meat quality measurements included muscle pH, color (L*, a* and b*), drip loss, cooking loss, peak shear force and six sensory traits including appearance (outside and inside), tenderness, juiciness, flavor and overall liking as well as carcass weight and probe yield. Thirty‐five SNPs with minor allele frequencies > 0.10 remained for the multimarker association using the GLM procedure of sas 9.2. Results showed that 20 SNPs were significantly associated with at least one of the traits with either additive or dominance or both effects (< 0.05). Among these significant SNPs, five of them in ADIPOQ, FTO, TNF, LEPR and AMPD1 had an effect on more than three traits simultaneously; those in MC4R, CAST, DGAT1 and MYF6 had an effect on two traits, while the others were associated with one trait. The results suggest that these markers could be incorporated into commercial pigs for marker‐assisted selection and breeding programs for carcass and meat quality trait improvement.  相似文献   

4.
Intramuscular fat (IMF) content and fatty acid composition affect the organoleptic quality and nutritional value of pork. A genome-wide association study was performed on 138 Duroc pigs genotyped with a 60k SNP chip to detect biologically relevant genomic variants influencing fat content and composition. Despite the limited sample size, the genome-wide association study was powerful enough to detect the association between fatty acid composition and a known haplotypic variant in SCD (SSC14) and to reveal an association of IMF and fatty acid composition in the LEPR region (SSC6). The association of LEPR was later validated with an independent set of 853 pigs using a candidate quantitative trait nucleotide. The SCD gene is responsible for the biosynthesis of oleic acid (C18:1) from stearic acid. This locus affected the stearic to oleic desaturation index (C18:1/C18:0), C18:1, and saturated (SFA) and monounsaturated (MUFA) fatty acids content. These effects were consistently detected in gluteus medius, longissimus dorsi, and subcutaneous fat. The association of LEPR with fatty acid composition was detected only in muscle and was, at least in part, a consequence of its effect on IMF content, with increased IMF resulting in more SFA, less polyunsaturated fatty acids (PUFA), and greater SFA/PUFA ratio. Marker substitution effects estimated with a subset of 65 animals were used to predict the genomic estimated breeding values of 70 animals born 7 years later. Although predictions with the whole SNP chip information were in relatively high correlation with observed SFA, MUFA, and C18:1/C18:0 (0.48–0.60), IMF content and composition were in general better predicted by using only SNPs at the SCD and LEPR loci, in which case the correlation between predicted and observed values was in the range of 0.36 to 0.54 for all traits. Results indicate that markers in the SCD and LEPR genes can be useful to select for optimum fatty acid profiles of pork.  相似文献   

5.
The polymorphisms of LEPR and MC4R genes are involved in appetite control mechanisms and indirectly associated with level of fat content in pig carcasses. Therefore, the aim of our study was to determine if both polymorphisms have an effect on components of colostrum and milk of sows. In our study we used gilts of two Polish breeds: Polish Landrace and Polish Large White, which belong to dam-line in Polish breeding. Colostrum and milk of sows were collected in 7, 14 and 21 day of lactation to assay solids, total protein, fat and lactose. The obtained results showed, that the observed mutation (G/A 1426 MC4R) had a significant effect mainly on the fat and solids content of colostrum. Animals with the MC4R AA genotype had 2.13 and 1.91 % (P ≤ 0.01) lower fat content of colostrum compared to sows with the MC4R GG genotype and heterozygous MC4R AG. The presence of the MC4R A allele in the animals’ genotype contributed to a decrease in fat and solids content of colostrum. The LEPR/HpaII mutation was found to have a considerable effect on the level of most colostrum components (fat, protein and solids) in both pig breeds. Significant decrease in the value of the colostrum components (except lactose) was observed only for animals with the allele LEPR B. The results obtained suggest that these genes might be used in selection of dam-line pigs as genetic markers of milk quality.  相似文献   

6.
Genetics of fat tissue accumulation in pigs: a comparative approach   总被引:2,自引:0,他引:2  
Fatness traits are important in pig production since they influence meat quality and fattening efficiency. On the other hand, excessive fat accumulation in humans has become a serious health problem due to worldwide spread of obesity. Since the pig is also considered as an animal model for numerous human diseases, including obesity and metabolic syndrome, comparative genomic studies may bring new insights into genetics of fatness/obesity. Input of genetic factors into phenotypic variability of these traits is rather high and the heritability coefficient (h 2) of these traits oscillates around 0.5. Genome scanning revealed the presence of more than 500 QTLs for fatness in the pig genome. In addition to QTL studies, many candidate gene polymorphisms have been analyzed in terms of their associations with pig fatness, including genes encoding leptin (LEP) and its receptor (LEPR), insulin-like growth factor 2 (IGF-2), fatty acid-binding proteins (FABP3 andFABP4), melanocortin receptor type 4 (MC4R), and theFTO (fat mass and obesity-associated) gene. Among them, a confirmed effect on pig fatness was found for a well-known polymorphism of theIGF-2 gene. In humans the strongest association with predisposition to obesity was shown for polymorphism of theFTO gene, while in pigs such an association seems to be doubtful. The development of functional genomics has revealed a large number of genes whose expression is associated with fat accumulation and lipid metabolism, so far not studied extensively in terms of the association of their polymorphism with pig fatness. Recently, epigenomic mechanisms, mainly RNA interference, have been considered as a potential source of information on genetic input into the fat accumulation process. The rather limited progress in studies focused on the identification of gene polymorphism related with fatness traits shows that their genetic background is highly complex.  相似文献   

7.
Genes involved in muscle lipid composition in 15 European Bos taurus breeds   总被引:1,自引:0,他引:1  
Consumers demand healthy and palatable meat, both factors being affected by fat composition. However, red meat has relatively high concentration of saturated fatty acids and low concentration of the beneficial polyunsaturated fatty acids. To select animals prone to produce particular fat types, it is necessary to identify the genes influencing muscle lipid composition. This paper describes an association study in which a large panel of candidate genes involved in adipogenesis, lipid metabolism and energy homoeostasis was tested for effects on fat composition in 15 European cattle breeds. Sixteen genes were found to have significant effects on different lipid traits, and among these, CFL1 and MYOZ1 were found to have large effects on the ratio of 18:2/18:3, CRI1 on the amount of neutral adrenic acid (22:4 n‐6), MMP1 on docosahexaenoic acid (22:6 n‐3) and conjugated linoleic acid, PLTP on the ratio of n‐6:n‐3 and IGF2R on flavour. Several genes – ALDH2, CHRNE, CRHR2, DGAT1, IGFBP3, NEB, SOCS2, SUSP1, TCF12 and FOXO1 – also were found to be associated with both lipid and organoleptic traits although with smaller effect. The results presented here help in understanding the genetic and biochemical background underlying variations in fatty acid composition and flavour in beef.  相似文献   

8.
An experiment was conducted to determine the effects of soy isoflavone daidzein on carcass characteristics, fat deposition, meat quality, and blood metabolites in finishing steers. Fourteen crossbred steers were used in a 120-d finishing study. These steers were stratified by weight into groups and randomly allotted by group to one of two dietary treatments: (1) control and (2) daidzein (500 mg/kg concentrate). The steers were fed a 90% concentrate diet. Supplemental daidzein did not affect slaughter weight, hot carcass weight, and dressing percentage, but tended to reduce fat proportion (not including intramuscular fat) in carcass and backfat thickness of steers. The carcass bone proportion was greater in steers fed daidzein diets than those fed control diets. Daidzein supplementation reduced pH at 24 h after slaughtered and moisture content and increased isocitrate dehydrogenase activity, fat content (16.28% and 7.94%), marbling score (5.29 and 3.36), redness (a*), and chroma (C*) values in longissimus muscle relative to control treatment. The concentrations of blood metabolites including glucose, blood urea nitrogen, triglyceride, total cholesterol, non-esterified fatty acid, high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) were all lower in steers fed daidzein diets than those fed control diets. Current results suggest that supplemental daidzein can affect lipid metabolism, increase intramuscular fat content and marbling score, and improve meat quality in finishing steers. Daidzein should be a promising feed additive for production of high-quality beef meat.  相似文献   

9.
The effects of castration age, dietary protein level and the dietary lysine/methionine (lys/met) ratio on animal performance, carcass characteristics and meat quality were studied in 64 intensively reared Friesian steers. Animals underwent castration procedures at 15 days old or at 5 months old. Dietary treatments started at 90 days old, with eight animals from each castration age randomly allocated to each treatment: 14.6% v. 16.8% CP (DM basis), and 3.0 v. 3.4 lys/met, on a 2×2×2 design. The recommended ratio of 3.0 was reached with supplementation of protected methionine. Steers were slaughtered at 443.5±26.2 kg live weight when they reached 12 months old approximately. Average daily gain, cold carcass weight or carcass classification were not affected by any studied effect. Muscle moisture (P=0.024), C18:2n-6 percentage (P=0.047), polyunsaturated fatty acid/saturated fatty acid (P=0.049) and n-6/n-3 (P=0.003) were higher in late castrated animals. Both high levels of dietary protein (P=0.008) and lys/met ratio (P=0.048) increased the percentage of muscle in the carcass. A level of 16.8% of CP in the diet also increased the percentage of monounsaturated fatty acids in the intramuscular fat (P=0.032), whereas a ratio lys/met of 3.4 decreased the percentage of saturated fatty acids (P=0.028). Thus, it is recommended using diets with a high protein level (16.8%) and a high lys/met ratio (3.4) in animals slaughtered at a young age, in order to obtain carcasses with high muscle content without negatively affecting productive traits or intramuscular fat composition.  相似文献   

10.
The objective of this study was to determine hepatic expression levels of GHR, IGF1R, IGF1 and IGF2 genes in young growing gilts at different developmental ages (60–210 days) in five pig breeds: Polish Large White (PLW), Polish Landrace (PL), Pulawska (Pul), Duroc (Dur) and Pietrain (Pie). We studied the differences among pig breeds as well as within each breed for pigs in different developmental ages. Obtained results revealed major differences among breeds in hepatic gene expression of porcine GHR, IGF1R, IGF1 and IGF2 genes in different developmental ages. The differences among breeds of GHR expression were significantly higher in PLW, PL at the age of 60, 90, 120 days as compared to Pul, Dur and Pie. In turn, the highest level of IGF1R expression was observed in PL at age of 150, 180 and 210 days, whereas in case of IGF1 the highest level was recorded in Pie gilts at the age of 60 and 90 days. Moreover trait associated study revealed highly significant correlations between hepatic expressions of IGF1R and IGF2 genes and carcass composition traits (P < 0.01) The results of study suggest that porcine GHR, IGF1R, IGF1 and IGF2 genes may be potential candidate genes for postnatal growth and carcass composition traits. Therefore, the implementation of the hepatic expression of GH/IGF genes into the pig breeding and gene assisted selection program in different pig breeds should be considered. However, further population wide study is needed to clarify the hepatic expression association with economic traits, such as body growth, meat quality and carcass composition traits.  相似文献   

11.
12.

Background

QTL affecting fat deposition related performance traits have been considered in several studies and mapped on numerous porcine chromosomes. However, activity of specific enzymes, protein content and cell structure in fat tissue probably depend on a smaller number of genes than traits related to fat content in carcass. Thus, in this work traits related to metabolic and cytological features of back fat tissue and fat related performance traits were investigated in a genome-wide QTL analysis. QTL similarities and differences were examined between three F2 crosses, and between male and female animals.

Methods

A total of 966 F2 animals originating from crosses between Meishan (M), Pietrain (P) and European wild boar (W) were analysed for traits related to fat performance (11), enzymatic activity (9) and number and volume of fat cells (20). Per cross, 216 (M × P), 169 (W × P) and 195 (W × M) genome-wide distributed marker loci were genotyped. QTL mapping was performed separately for each cross in steps of 1 cM and steps were reduced when the distance between loci was shorter. The additive and dominant components of QTL positions were detected stepwise by using a multiple position model.

Results

A total of 147 genome-wide significant QTL (76 at P < 0.05 and 71 at P < 0.01) were detected for the three crosses. Most of the QTL were identified on SSC1 (between 76-78 and 87-90 cM), SSC7 (predominantly in the MHC region) and SSCX (in the vicinity of the gene CAPN6). Additional genome-wide significant QTL were found on SSC8, 12, 13, 14, 16, and 18. In many cases, the QTL are mainly additive and differ between F2 crosses. Many of the QTL profiles possess multiple peaks especially in regions with a high marker density. Sex specific analyses, performed for example on SSC6, SSC7 and SSCX, show that for some traits the positions differ between male and female animals. For the selected traits, the additive and dominant components that were analysed for QTL positions on different chromosomes, explain in combination up to 23% of the total trait variance.

Conclusions

Our results reveal specific and partly new QTL positions across genetically diverse pig crosses. For some of the traits associated with specific enzymes, protein content and cell structure in fat tissue, it is the first time that they are included in a QTL analysis. They provide large-scale information to analyse causative genes and useful data for the pig industry.  相似文献   

13.
Cathepsins, growth hormone-releasing hormone (GHRH) and leptin receptor (LEPR) genes have been receiving increasing attention as potential markers for meat quality and pig performance traits. This study investigated the allele variants in four cathepsin genes (CTSB, CTSK, CTSL, CTSS), GHRH and LEPR in pure-bred Ukrainian Large White pigs and evaluated effects of the allele variants on meat quality characteristics. The study was conducted on 72 pigs. Genotyping was performed using PCR–RFLP technique. Meat quality characteristics analysed were intramuscular fat content, tenderness, total water content, ultimate pH, crude protein and ashes. A medium level of heterozygosity values was established for GHRH and LEPR genes which corresponded to very high levels of informativeness indexes. Cathepsins CTSL, CTSB and CTSK had a low level of heterozygosity, and CTSS did not segregate in this breed. Association studies established that intramuscular fat content and tenderness were affected by the allele variance in GHRH and LEPR but not by CTSB and CTSL genes. The GHRH results could be particularly relevant for the production of lean prime cuts as the A allele is associated with both, a lower meat fat content and better tenderness values, which are two attributes highly regarded by consumers. Results of this study suggest that selective breeding towards GHRH/AA genotype would be particularly useful for improving meat quality characteristics in the production systems involving lean Large White lines, which typically have less than 2 % intramuscular fat content.  相似文献   

14.
MyoG基因的遗传效应分析   总被引:11,自引:1,他引:10  
朱砺  李学伟 《遗传》2005,27(5):710-714
实验采用PCR-RFLP技术分析了不同品种猪MyoG基因3′端MspⅠ位点的多态性,应用单标记回归模型分析了不同基因型与相关性状间的关联性及不同等位基因的遗传效应。结果表明:N等位基因能极显著地增加胴体瘦肉率和眼肌面积,降低皮脂含量(P<0.01),改善胴体产肉量和提高胴体品质;同时,不同基因型对肉质性状的遗传影响作用较大,表现为N等位基因能极显著地降低猪肉品质,使pH值、肉色和肌内脂肪含量降低,并使肌肉的系水力变差(P<0.01)。N等位基因对增加胴体瘦肉率的加性效应值和显性效应值分别为3.929%和-0.602%;对增加眼肌面积的加性效应值和显性效应值分别为2.0985 cm2和-0.5775 cm2;对皮脂率的加性效应值为-3.0245%,显性效应值为-0.4045%。N等位基因对pH1的加性效应值和显性效应值分别为-0.167和0.034;对贮藏损失的加性效应值和显性效应值分别为0.558和-0.347;对肌内脂肪含量的加性效应值和显性效应值分别为-0.963和-0.217。但MyoG基因3′端MspⅠ位点的突变对FOM肉脂仪测定的胴体等级性状的影响不显著(P>0.05)。  相似文献   

15.
Subcutaneous fat thickness and fatty acid composition (FAC) play an important role on seasoning loss and organoleptic characteristics of seasoned hams. Dry-cured ham industry prefers meats with low contents of polyunsaturated fatty acids (PUFA) because these negatively affect fat firmness and ham quality, whereas consumers require higher contents in those fatty acids (FA) for their positive effect on human health. A population of 950 Italian Large White pigs from the Italian National Sib Test Selection Programme was investigated with the aim to estimate heritabilities, genetic and phenotypic correlations of backfat FAC, Semimembranosus muscle intramuscular fat (IMF) content and other carcass traits. The pigs were reared in controlled environmental condition at the same central testing station and were slaughtered at reaching 150 kg live weight. Backfat samples were collected to analyze FAC by gas chromatography. Carcass traits showed heritability levels from 0.087 for estimated carcass lean percentage to 0.361 for hot carcass weight. Heritability values of FA classes were low-to-moderate, all in the range 0.245 for n-3 PUFA to 0.264 for monounsaturated FA (MUFA). Polyunsaturated fatty acids showed a significant genetic correlation with loin thickness (0.128), backfat thickness (−0.124 for backfat measured by Fat-O-Meat’er and −0.175 for backfat measured by calibre) and IMF (−0.102). Obviously, C18:2(n-6) shows similar genetic correlations with the same traits (0.211 with loin thickness, −0.206 with backfat measured by Fat-O-Meat’er, −0.291 with backfat measured by calibre and −0.171 with IMF). Monounsaturated FA, except with the backfat measured by calibre (0.068; P<0.01), do not show genetic correlations with carcass characteristics, whereas a negative genetic correlation was found between MUFA and saturated FA (SFA; −0.339; P<0.001). These results suggest that MUFA/SFA ratio could be increased without interfering with carcass traits. The level of genetic correlations between FA and carcass traits should be taken into account in dealing with the development of selection schemes addressed to modify carcass composition and/or backfat FAC.  相似文献   

16.
Melanocortin 4 receptor (MC4R) plays a crucial part in regulating feeding behavior in humans and rodents. We detected two single nucleotide polymorphisms (SNPs; c.108G → A and c.627C → T) in the goose MC4R gene and genotyped 94 Landes geese for association analysis with several carcass traits. Significant associations (P < 0.05) were obtained for c.108G → A with carcass weight, breast muscle percentage, and leg muscle percentage, and for c.627C → T with body weight, carcass weight, semi-eviscerated weight, and eviscerated weight. We re-constructed haplotypes based on the two SNPs and analyzed diplotypes in association with carcass traits, obtaining significant associations with several of the traits. These results suggest that polymorphisms in the MC4R gene could have effects on carcass traits in Landes geese. More study is required to confirm these results.  相似文献   

17.
18.
For detecting QTL in the whole swine genome, 1068 pigs from three F2 populations constructed by crossing European Wild boar and Pietrain (W×P), Meishan and Pietrain (M×P), and Wild Boar and Meishan (W × M) were genotyped for genetic markers evenly spaced at approximately 20 cM intervals. AQTL analysis was performed using a least-squares method. Here the results of the QTL analysis on the porcine chromosome 7 are presented. QTL for carcass composition (e.g. head weight, carcass length, backfat depth, abdominal fat and bacon meat) were mapped in the chromosomal region CYPA/CYPD-TNFB-S0102 in M×P and W×M, but not in W×P. The QTL explained 5.3%–27.2% of the F2 phenotypic variance in the two F2 populations. Most traits affected by the mapped QTL were related to carcass fatness. The mode of gene action of QTL was additive. Surprisingly, in contrast to the parental phenotype, the QTL alleles from fatty Meishan were associated with thinner backfat than Pietrain and Wild Boar alleles, suggesting that the genome of the fatty Meishan pig contains genes which can reduce fat content of carcass substantially.  相似文献   

19.
A QTL study of live animal and carcass traits in beef cattle was carried out in New Zealand and Australia. Back‐cross calves (385 heifers and 398 steers) were generated, with Jersey and Limousin backgrounds. This paper reports on weights of eight organs (heart, liver, lungs, kidneys, spleen, gastro‐intestinal tract, fat, and rumen contents) and 12 fat composition traits (fatty acid (FA) percentages, saturated and monounsaturated FA subtotals, and fat melting point). The New Zealand cattle were reared and finished on pasture, whilst Australian cattle were reared on grass and finished on grain for at least 180 days. For organ weights and fat composition traits, 10 and 12 significant QTL locations (P < 0.05), respectively, were detected on a genome‐wide basis, in combined‐sire or within‐sire analyses. Seven QTL significant for organ weights were found at the proximal end of chromosome 2. This chromosome carries a variant myostatin allele (F94L), segregating from the Limousin ancestry, and this is a positional candidate for the QTL. Ten significant QTL for fat composition were found on chromosomes 19 and 26. Fatty acid synthase and stearoyl‐CoA desaturase (SCD1), respectively, are positional candidate genes for these QTL. Two FA QTL found to be common to sire groups in both populations were for percentages of C14:0 and C14:1 (relative to all FAs) on chromosome 26, near the SCD1 candidate gene.  相似文献   

20.
The aim of this investigation was to characterise the fatty acid composition within intramuscular fat (IMF) of two muscles (breast and thigh) from 28 pheasants, ten wild ducks and 27 black coots from Slovakia. A high variability for all single fatty acids (FA) and the total fat concentration in muscles of wild birds was identified. Black coots deposited the highest fat in breast muscle whereas wild ducks and pheasants accumulated more lipids in thigh muscle. In general, the content of polyunsaturated fatty acids (PUFA) of the IMF in wild bird muscles was high, and the saturated FA concentration was lower compared with muscles of domestic farm animals. The ratio between PUFA and saturated fatty acids (PSQ) ranked between 0.6 and 1.2, and the ratio of n-6/n-3 fatty acid was favourably low in black coot and wild pheasants (3.2 and 2.9, respectively). Farmed pheasants had increased IMF and more saturated and n-6 fatty acids deposited in thigh muscle but not in breast muscle.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号