Effects Of Starvation On AMPK And Related Enzyme Activities, Glycolysis And Meat Quality Of Tibetan Sheep

Tibetan sheep are gradually formed by long artificial nurtured and naturenurtured, With characteristic of plateau species, living in an altitude of3000m-5000m above the alpine region. Compared with other livestock and poultry,lamb has high protein, high energy, lower fat, low cholesterol, more and more get thefavour of consumer, has a broad market. However, seasonal nutrition disequilibriumcause hunger stress, long-distance transport or long dirve cause stress in theproduction of Tibetan sheep have a great influence on the growth development,reproductive performance and meat quality after slaughter. AMPK is known as thereceptor metabolism of the body, plays an important role in the adapt and resist stressof animals. This research in cloning AMPK three subunits Prkag, Prkaa and Prkab;Detection of three genes expression in Tibetan sheep organizations mode; Analysisof the key enzymes of the saccharides and lipid metabolism, AMPK, acetyl-coacarboxylase(ACC) and glycogen synthetase(GS) three enzymes distribution inTibetan sheep. Study the hunger stress effect（Normal breeding、Hunger for24h、Hunger for48h、Supplementary feed after hunger） on the three kinds of enzymeactivities, muscle glycolysis indicators and muscle quality indicators, preliminaryclarified the relationship between hunger stress and the change of enzyme activities,meat quality, in order to by preventing stress to improve meat quality providing thetheoretical foundation. The main results were as follows：（1）The Prkag、Prkaa、Prkab genes were widely distribution in the skeletalmuscle、heart、liver、spleen、lung、kidney and intestine of Tibetan sheep, theexpression level is different.（2）Research results, hunger stress can make Prkag gene expressed isincreased in heart, liver and skeletal muscle of Tibetan sheep; Prkaa gene expressedis significantly in skeletal muscle, slightly increased in heart and liver; Prkab geneexpressed only in skeletal muscle has a rise tendency and little change in heart andliver. （3）AMPK,ACC and GS are widely distribution in the skeletal muscle、heart、liver、spleen、lung、kidney and intestine of Tibetan sheep, the expression level isdifferent. Hunger stress make the AMPK activities increased, the ACC and GSactivities decreased in skeletal muscle, liver, kidney and intestine.（4）Hunger stress for short time(not more than24hour) can not makesignififcantly affect on the AMPK、ACC、GS activity, glycolysis indicators and meatquality. But hunger stress for long time(more than48hour) can make the AMPKactivity increased, the ACC and GS activity declined, the glycogen content decreased,the LD content increased, the lower pH value, the cooked meat percentage and driploss decreased, the shearing force increased.（5）In the different parts meat of Tibetan sheep, the AMPK activity is: bicepsfemoris musculi colli longissimus dorsi, the glycolysis indicators is: bicepsfemoris longissimus dorsi musculi, the cooked meat percentage and drip loss oflongissimus dorsi is largest, the shearing force of biceps femoris is largest. Hungerstress have different influence on the different parts meat, the glycolysis indicatorsand meat quality of biceps femoris have the largest influence.This study can prove that hunger stress can changing the AMPK、ACC and GSactivity, affect the speed of muscle glycolytic, affect the muscle quality of Tibetansheep after slaughtered. Bring great influence to the production of Tibetan sheep, hasa harmful effect on farming.