Influence Of Compound Plant Extract On Growth Performance, Meat Quality And Disease Resistance Of Yellow-feathered Broilers

This experiment was conducted to study the effects of different compound plant extract levels on growth performance,meat quality and disease resistance of yellow-feathered broilers.To explore the suitable amount of compound plant extracts added in poultry feed,compound plant extracts as feed additives provide theoretical basis for the quality of poultry production.Experiment 1Effects of different compound plant extract levels on growth performance and meat quality.240 one-day-old cock of yellow-feathered broilers(initial body weight(BW):29.21±2.07 g)were individually weighed and assigned to 1 of 4 dietary treatments(10 replicate cages/treatment and 6 broiler chickens/cage)based on their BW.Group A:the basal diet was fed,B,C and D were fed diets containing 0.01%,0.02%and0.04%of plant extracts in basal diet.Slaughter experiments were carried out at 35 and70 days of age.The results were as follows:1.Effects of different levels of compound plant extracts on growth performance of yellow-feathered broilers.Different levels of compound plant extracts were added to the diet.Compared with A,increased significantly during the whole experiment yellow-feathered broilers end weight(P<0.05),average daily gain(P<0.05),decreased feed conversion ratio(P<0.05).A significant increase eviscerating percentage and semi-eviscerated weight of 35-day-old D group(P<0.05).When the level of addition is 0.02%,the rate of abdominal fat is the lowest.There was no significant difference in the breast muscle rate and the leg muscle rate among the groups of A,B,C and D(P>0.05).In the study of blood biochemical index and antioxidant index,it is found that adding compound plant extracts can significantly increase the TP and HDL-CH content and reduce CHOL and LDL-CH content(P<0.05).The content of GSH-PX increased significantly(P<0.05),and the content of MDA decreased(P<0.05)in group C and D with the addition level of 0.02%and 0.04%.In the study of the intestinal morphology at the age of 35 days and 70 days,compared with duodenum,jejunum and ileum of the height of the villi,the depth of the recess and the thickness of the myometrium in group C with 0.02%compound plant extracts added were improved significantly(P<0.05).There was no significant effect on the relative length and relative weight of the duodenum,jejunum and ileum(P>0.05).Compared with the control group,the pestilence index was significantly improved(P<0.05).Adding level to 0.02%is the best.2.Effects of different levels of compound plant extracts on meat quality of yellow-feathered broilers.Different levels of compound plant extracts of adding to the diet can significantly improve the breast and leg muscle pH value of 70-day-old by yellow-feathered broilers(P<0.05).There was no significant difference in muscle shear force at the age of 35 days and 70 days(P<0.05).It was reduced the fat content in the chest and leg muscles during the whole test period and improved the protein content of 70-day-old by yellow-feathered broilers in muscle(P<0.05).There is no significant difference in the content of water and ash in the normal nutritional components of the muscles(P>0.05).Improving the content of essential amino acids,flavored amino acids and total free amino acids in the 35 day and 70 day old breast and leg muscles(P<0.05).Increasing the content of essential fatty acids,DHA and EPA in muscles(P<0.05).Comprehensive analysis,adding 0.02%of plant extracts in the diet can significantly improve muscle flavor and improve muscle quality.Experiment 2Effects of compound plant extracts on disease resistance of yellow-feathered boilers.A total of 144 Yellow-feathered Broilers at 1 day age were randomly divided into six group,A,B,C,D,E,F,four repeats for each group,and six for each repeat,isolation breeding.Group A and D:the basal diet was fed;Group B and E:0.02%compound plant extracts were added to the basal diet;Group C and F:10%colistin sulfate was added to the basal diet;According to the challenge model,the best dose was 1ml at the age of 21 days.That is A,B,C three groups,each chicken breast injection 1ml physiological saline,D,E,F three groups,each chicken breast injection1ml Escherichia coli bacteria(including bacteria 1.6×10~9cfu/ml).D,E,F group were A,B,C control group.The mortality rates within 72h were observed and the status of each chicken was observed.After 72h,the remaining chickens were slaughtered,the blood was taken from the heart and the spleens were taken to determine the lymphocyte transformation rate.The results were as follows:Adding the compound plant extract in diets can significantly improve the resistance of Escherichia coli in yellow-feathered broilers,reduce mortality.The content of IgM in the non attack group(P<0.05)was improved significantly,and the content of IgA in the attack group was improved(P<0.05).Improvement of lymphocyte transformation rate and spleen lymphocyte transformation rate in peripheral blood after attack of poison(P<0.05).Thus improve the disease resistance of the body.