Analysis Of Meat Quality Traits And Screening For Differential Genes In Jingyuan Chicken

The Jingyuan chicken is one of the best local breeds in Ningxia and is characterised by its delicious meat quality and unique flavour.In order to increase its meat production and further improve its meat quality,it is important to determine and analyse the slaughter performance and meat quality traits of the Jingyuan chicken at different ages.In the present study,30 healthy male and female Jingyuan chickens were selected at 42,126 and 180 days of age under the same feeding management conditions,and their slaughter performance,general physical parameters(pH,meat colour,shear force,drip loss),nutritional composition(moisture,ash,protein,intramuscular fat)and cholesterol,amino acids,fatty acids,inosine and inosinic acid content were measured and analysed,based on phenotypic traits.Transcriptome sequencing analysis was carried out on their muscle tissues to screen for differential genes,and the main enrichment pathways and differential genes related to meat quality were screened out through bioinformatics analysis,with the main findings as follows:1.At 42,126 and 180 days of age,the analysis of slaughter performance and physical indicators of Jingyuan chickens showed that:the slaughter rate,half-cleaning rate and full-cleaning rate of Jingyuan chickens showed a decreasing trend with increasing age;the breast muscle rate and leg muscle rate showed an increasing trend with increasing age.In both hens and cocks,Ph value,shear force and drip loss rate were significantly or highly significantly different between breast and leg muscles;meat colour a(red-greenness value)values showed an increasing trend with age,b(yellow-blueness value)values showed no significant pattern,and L(brightness value)values all showed the highest at 126 days of age.2.At 42,126 and 180 days of age,the results of the analysis of the meat quality and nutrient content of Jingyuan chickens showed that the crude moisture content of the breast and leg muscles of both hens and cocks was highest at 42 days of age,followed by 180 days of age and lowest at 126 days of age;the crude ash content showed no obvious pattern;in hens,the content of intramuscular fat in the breast and leg muscles The protein content of pectoral muscle was significantly higher than that of leg muscle at all three ages(P<0.01);the cholesterol content of cocks was significantly higher than that of hens(P<0.01);the content of fresh tasting amino acids was higher in the muscle of hens;the inosine content of hens was significantly higher than that of cocks(P<0.01);and the inosinic acid content of cocks was significantly higher than that of hens(P<0.01).3.Through transcriptome sequencing analysis of muscle tissues of 42,126 and 180 days old Jingyuan chickens,a total of 2216 differential genes were screened,including 1286 up-regulated genes,930 down-regulated genes and 323 related enrichment pathways,among which the functional enrichment of genes related to meat quality was mainly concentrated in MAPK,PPAR and adipocyte factor signalling pathways,but there were also a small number of genes in fatty acid metabolism and However,a small number of differential genes were also enriched in fatty acid metabolism and fatty acid degradation pathways.The above findings provide a theoretical basis for the improvement of meat quality,the molecular mechanism of meat quality control and the development and utilization of local breed resources,and also provide some theoretical support for the selection and breeding of Jingyuan chicken breeds.