Effects Of Rosmarinic Acid On Growth Performance、Meat Quality And Antioxidant Performance Of Yellow Feather Broilers

Rosmarinic acid(RA)is an active substance extracted from natural plants such as rosemary.It has the functions of anti-oxidation,anti-inflammatory and bacteriostasis.The purpose of this experiment is to explore the effects of rosmarinic acid on growth performance,nutrient utilization,meat quality and other indexes of yellow feather broilers,and then find out the effective addition concentration,so as to provide a certain theoretical and experimental basis for the subsequent application of rosmarinic acid in animal production.360 1-day-old yellow feather broilers(whole females)were randomly divided into 6groups with 6 replicates in each group and 10 feathers in each replicate for 56 days.The control group was fed with basic diet,and the experimental group was supplemented with 50,100,150,200 and 400 mg / kg rosmarinic acid respectively.At the age of 57 days,one chicken was slaughtered at random for each repetition,and relevant samples were collected for detection.The results are as follows:1)Growth performance: the results of statistical analysis showed that the addition of rosmarinic acid to feed had a significant effect on the average daily gain of yellow feather broilers in the early stage of the experiment(P<0.05).Compared with the control group,the addition of 100 mg / kg rosmarinic acid in the diet had a significant effect on the average daily gain of yellow feather broilers(P<0.05),increased by 5.2%.The average daily gain,average daily feed intake and feed to meat ratio of each experimental group were not significant on the 28 th to 56 th days and 1 to 56 th days(P>0.05).2)Nutrient utilization: the results of statistical analysis showed that the addition of rosmarinic acid to feed had a significant effect on the digestibility of crude protein and crude fat of yellow feather broilers(P<0.05).Compared with the control group,adding rosmarinic acid to the diet could significantly improve the digestibility of crude protein and crude fat(P<0.05),and adding 100 mg / kg rosmarinic acid increased the digestibility of crude protein by 8.9%;The digestibility of crude fat increased by 14.8% and 9.2% with the addition of100 mg / kg and 400 mg / kg rosmarinic acid.The digestibility of crude fiber,calcium and phosphorus in each experimental group had no significant effect(P>0.05).3)Slaughter index: statistical analysis showed that the addition of rosmarinic acid to feed had no significant effect on the slaughter performance of yellow feather broilers(P>0.05).4)Immune organ index: statistical analysis showed that the addition of rosmarinic acid to feed had a significant effect on the thymus index of yellow feather broilers(P<0.05).Compared with the control group,adding 200 mg / kg rosmarinic acid to the diet could significantly improve the thymus index of yellow feather broilers(P<0.05).All experimental groups had no significant effect on bursa index and spleen index(P<0.05)5)Meat quality: the results of statistical analysis showed that the addition of rosmarinic acid to feed had a significant effect on the redness value and drip loss value of yellow feather broilers(P<0.05).Compared with the control group,adding rosmarinic acid to the diet could significantly increase the redness value(P<0.05).Adding rosmarinic acid to the diet could significantly reduce the drip loss of pectoral muscle of yellow feather broilers(P<0.05).Each experimental group had no significant effect on brightness value,yellowness value,pH value and water loss rate(P>0.05).6)The results of statistical analysis showed that the addition of rosmarinic acid to feed had a significant effect on the activities of GSH Px,MDA and T-AOC in yellow feather broilers(P<0.05).Compared with the control group,adding 200 and 400 mg / kg rosmarinic acid to the diet could significantly increase the activity of serum GSH PX(P<0.05);Adding50 mg / kg rosmarinic acid could significantly reduce the activity of serum MDA(P<0.05);The addition of 150,200 and 400 mg / kg rosmarinic acid can significantly improve the activity of serum T-AOC.All experimental groups had no significant effect on serum cat and SOD(P>0.05).7)Jejunal digestive enzyme activity: the results of statistical analysis showed that adding rosmarinic acid to feed had no effect on yellow feather broilers α-Amylase activity was significantly affected(P<0.05).Compared with the control group,adding 100 mg / kg rosmarinic acid to the diet could significantly improve the jejunum of yellow feather broilersα-Amylase activity(P<0.05)had no significant effect on jejunal digestive enzyme activity in other experimental groups(P>0.05).Based on the above research results.Adding rosmarinic acid to the diet of yellow feather broilers can improve daily weight gain,intestinal digestive enzyme activity and nutrient utilization,improve muscle color and breast muscle water retention by improving antioxidant capacity.The recommended dosage is 100 ～ 150 mg / kg.