Effects of Transport Stress on Meat Quality and Mechanism in Broiler Chickens
|School||Northwest University of Science and Technology|
|Course||Animal Nutrition and Feed Science|
|Keywords||Transport stress Broilers Muscle Quality Gene Expression|
The paper system to study the blood biochemical indicators of transport stress on broiler carcass quality, muscle fiber, muscle energy metabolism, muscle lipid oxidation and regulating gene mRNA expression, explore the transport affect broiler meat quality of possible mechanism. Selection of 360 46-day-old healthy AA broilers male chicks were randomly assigned to five treatment groups and the control group were not transported, the other four treatment using a 2 x 2 factorial design, processing factors transport time (45 and 180 min, respectively) transportation end to the slaughter interval (45 and 180 min). Each treatment six replicates of 12 birds. To test the impact of a transport stress on broilers blood stress indicators and muscle quality. Compared with the control group, the broiler plasma corticosterone levels in 45 min/45 min (transit time / rest time) group was significantly higher (P lt; 0.05), but with the increase of transport and rest time before it fell to transport level. Rest time to a certain extent affect broiler plasma corticosterone levels, and the rest 45 min group broiler plasma corticosterone than 180 min rest group (P = 0.05) after transport. Rest time of 24 h pectoral muscle after slaughter L * values ??(P = 0.07) and a * values ??(P = 0.02) have a certain impact, low 180 min rest group L * value, a * value higher (P gt; 0.05). Transport time and rest time interaction effect on the measured indicators were not significant (P gt; 0.05). Tests showed that transportation stress can cause elevated the broilers plasma corticosterone, so that the body is in a strong stress, a longer time to rest after transport helps to reduce the stress level of the broiler, relieve muscle quality decline. To test the impact of the two transport stress on the muscle glycolytic potential broiler blood biochemical indicators and different fibers. Transit time significantly affected the the broiler plasma glucose (P lt; 0.05), type IIa muscle fiber area of ??the chest muscle glycogen content (P = 0.06) and leg (P lt; 0.01) and density (P lt; 0.01). Plasma glucose increased slightly after 45 min of transport, while significantly lower (P lt; 0.05) at 180 min transport group. Long transport significantly reduces the pectoral muscle glycogen content, be affected by reducing the area of ??type IIa muscle fibers in the leg muscle and increase its density and its contraction. Transport long after the rest can be significantly reduced in broiler leg muscle glycogen (P LT; 0.05), lactic acid (P lt; 0.01) content and glycolysis potential (GP, P lt; 0.01). In addition, 180 min/180 min of broilers plasma non-esterified fatty acid (NEFA) levels were significantly higher (P lt; 0.05). The tests showed that the transport may affect the state of contraction of the muscle fibers, and enhance muscle glycolysis and lipolysis. Long time the rest of the transport (especially long transport) can relieve muscle contraction, reduce muscle glycolysis, is conducive to the formation of better meat quality. The test three transport stress on broilers muscle lipid oxidation and ATP content and its molecular mechanism. The transit time significantly affect broiler leg muscle ROS production (P = 0.01), chest, leg muscle ATP content (P lt; 0.01, P lt; 0.01), EC (P lt; 0.01, P lt; 0.01) and pectoral muscle ATP / ADP ratio (P lt; 0.01), and the leg muscle avUCP mRNA the expression amount (P LT; 0.01). 180 min transport significantly increased ROS production in broiler leg muscle ATP content and EC values, significantly reduce the pectoral muscle ATP content, ATP / ADP ratio and EC values. In addition, 180 min transport a significant increase in the amount of the leg muscle avUCP mRNA expression. Transport increased significantly after 180 min of rest broiler leg muscle ATP (P lt; 0.01) and ADP (P = 0.03) content, and avANT (P = 0.01) and avPGC-1αmRNA (P lt; 0.01) the expression significantly reduce the pectoral muscle EC (P = 0.03). Transport time and rest time interactions significantly affect leg muscle ATP (P lt; 0.01) content, EC (P lt; 0.05) and avUCP mRNA expression levels (P lt; 0.05). The tests showed that the transport stress exacerbated broiler skeletal muscle energy metabolism and lipid peroxidation process, long rest after the transport can reduce broiler skeletal muscle energy metabolism, help the body to scavenge free radicals, reduce damage to the skeletal muscle cells, which will help maintain good muscle quality.