Polyunsatuated Fatty Acids Of Flaxseed Enrichment In Different Tissues And Its Effect On Carcass Qualities In Growing-finishing Pigs

Long-chain unsaturated fatty acids, especially the n-3 polyunsaturated fatty acids are crucial and beneficial for human health. Pork is a most important meat in human food, so it is significant to increase the content of n-3 polyunsaturated fatty acids for getting appropriate proportion of all fatty acids in pork. In this thesis, flaxseed which is rich in n-3 polyunsaturated fatty acids was added to diet of growing-finishing pigs in order to improve the fatty acids profiles, and to increase both the content of n-3 polyunsaturated fatty acids and DHA in pork. A gas chromatography method which is suitable for the analysis of fatty acids composition in various tissues of pigs was set up in this study. The results showed that the fatty acids composition of various tissues in pigs varied with additive time of flaxseed to diets. The effects of flaxseed additive time on growth performance, carcass traits and meat qualities in pigs were also studied in this thesis. The details were as follows:1. The experiment was carried out to establish a simple gas chromatography method suitable for the analysis of fatty acids composition of various tissues in pigs. Different pretreatment methods were used for different tissues. Benzene-petroleum ether — KOH-methanol method was used for muscle and chloroform-methanol—KOH-methanol method was used for adipose and liver. The CP-3800 gas chromatography equipped with a 1177 injector, a flame ionization detector and a capillary chromatographic column CPSi188 for FAME (50m×0.25mm id × 0.20μm) was used in this experiment. The injector temperature was 250℃, detector temperature was 270℃, column flux was 1.0mL/min, split ratio was 1:100. The temperature program was as follow: 100℃ at first, increase to 200℃ at 5℃/min and hold 5min, increase to 225℃ at 2℃/min and hold 2min. The total analysis time was 39.5min. It can get good separation of base line for measuring the mixture of fatty acid methyl esters and less analytic time in this method and the chromatograms had the peaks of good shape and less impurity. The results of the degree of precision assay indicated that this method have achieved the demand of measurement. The qualitative measurement adopted the mixed standard and several single standards together. The mixed standard is more economical than all single standards and can get the similar effect. Above method is convenient, economical, quick, high sensitivity and precision. It is suited to study compartment analysis about compound of long-chain unsaturated fatty acids.