| With the booming of global and domestic broiler markets in recent decades,the resulting problems of antibiotic abuse and drug residues emerge in an endless succession,especially in white-feathered broiler.The abuse of antibiotics and drug residues will not only bring harm to animal food safety,but also seriously threaten human health and environmental safety.It is urgent to find alternatives to antibiotics.Yellow-feathered broiler is more and more popular with consumers.However,the breeding of yellow-feathered broilers is characterized by slow growth,long feeding time,and high risk of epidemic diseases.Therefore,this study started from the aspects of improving the growth rate of broilers and reducing the risk of disease.According to relevant literature reports and compatibility taboos with the characteristics of qingrejiedu,gas-solid table,functions of the dehumidifying effect,and so on,six traditional Chinese medicines(radix isatidis,common cnidium fruit,astragalus root,duhuo,dangshen,Chinese angelica)were selected,they were mixed at the ratio of 3:1:3:1:2:2 and added to the foodstuff of chicken,which acted as a Chinese herbal medicine feed additive for replacing antibiotics and drugs used in the process of cultivation.120 Sanhuang chicken with a initial weight about 600 g(P > 0.05)were selected,and were randomly divided into control group and experimental group 1,group 2,group 3(was added in the basic diet,respectively 1%,2%,3% of the Chinese herbal medicine).After being raised for 15 days or 30 days,determinations of growth performance,immune performance index,and the antioxidant index were carried out to provide certain references for researches and developments of Chinese herbal medicine feed additive.Part 1: Effects of six kinds of herbs on growth performance of broilersGrowth performance is the most intuitive index to measure the development of livestock and poultry.In order to explore the influences of six herbs on the growth performance of broilers,the body weight and feed intake of broilers were counted every 3 days,and the average body weight,average daily weight gain,average daily feed intake and feed to meat ratio and mortality of broilers were calculated.The results were as follows :(1)The average body weight of each experimental group on day 15 and day 30 was significantly higher than that of the control group(P<0.01).(2)Compared with the control group,the average daily weight gain of each experimental group was significantly increased at day 0 to day 15(P<0.01).The average daily food intake was significantly reduced(P<0.01),but there was no significant difference between the three treatment groups(P>0.05).The raw meat ratio of each experimental group was significantly lower than that of the control group(P<0.01),and there was no significant difference between the experimental group 2 and the experimental group 3(P>0.05).(3)During the period from day 15 to day 30,compared with the control group,the average daily weight gain in each experimental group was significantly increased(P<0.01),and the average daily food intake and feed to meat ratio were significantly reduced(P<0.05).(4)For the whole period(day 0 to day 30),compared with the control group,the average daily weight gain in each experimental group was significantly increased(P<0.01),and the average daily food intake and feed to meat ratio were significantly reduced(P<0.05).(5)The survival rate of experimental group 1 and experimental group 3 was not significantly different from that of the control group(P>0.05).The survival rate of the experimental group 2 was significantly higher than that of the control group(P<0.05),and higher than that of the experimental group 1 and experimental group 3,but there was no significant difference between the survival rates of the three experimental groups(P>0.05).The results showed that adding six herbs into the diet could improve the average weight,average daily weight gain and survival rate of broilers,reduce the average daily food intake and feed to meat ratio of broilers,and improve the performance of broilers.Among them,the adding proportion of 2% and 3% is more significant.Part 2: Effects of six kinds of herbs on immune performance of broilersImmune function is related to the body’s resistance to disease.In order to explore the effects of Chinese herbal medicine feed additive on poultry immune performance,immune organ index was calculated,lymphocyte conversion rate was determined with MTT method,the contents of immunoglobulin(IgG,IgM,and IgA)and complement (C3 and C4)was determined using ELISA method,and the expression level of cytokines(IL-2 and IFN-γ)was determined by RT-qPCR.The results were as follows :(1)Compared with the control group,thymus index in each test group was significantly improved(P<0.05),spleen indexes in treatment group 1 and treatment group 3 were significantly improved(P<0.05),and there was no significant difference in bursa index between each group(P>0.05).(2)There was no significant difference in the lymphocyte conversion rate between the experimental group 1 and the control group(P>0.05),and the lymphocyte conversion rates in both groups were significantly lower than that in treatment group 2 and treatment group 3,respectively(P<0.01).(3)At day 15,the content of IgG in each experimental group was significantly higher than that in the control group(P<0.05).There was no significant difference in contents of IgM and IgA among these groups(P>0.05).At day 30,compared with the control group,the contents of IgG and IgM in each treatment group were significantly increased(P<0.01),but there was no significant difference in the content of IgM among treatment groups(P>0.05),and no significant difference in the content of IgA among groups was observed(P>0.05).(4)On day 15,the content of C3 in each experimental group was significantly higher than that in the control group(P<0.05).The difference of C4 content between the treatment group 2,treatment group 1 and the control group was not significant(P>0.05),and the experimental group 3 was significantly higher than that in other groups(P<0.01).At day 30,the contents of C3 and C4 in each experimental group were significantly higher than these in the control group(P<0.01),but there was no significant difference in the contents of C4 among treatment groups(P>0.05).(5)Compared with the control group,the expression level of IL-2 mRNA in each treatment group was significantly up-regulated(P<0.01),but there was no significant difference between treatment group 2 and treatment group 3(P>0.05).Compared with the control group,the expression level of IFN-γ mRNA in experimental group 1 and 2 was not significantly different(P>0.05).Compared with the control group,the expression level of IFN-γ mRNA in treatment 3 was significantly increased(P<0.01).The results showed that adding six herbs to the diet could improve the immune organ index of broilers,and promote the transformation of T lymphocytes into lymphocytes.At the same time,the contents of immunoglobulin and complement in broiler serum and the expression level of cytokine(IL-2 and IFN-γ)mRNA were increased,which contributed to improving the immune performance of broiler.Part 3: Effects of six kinds of herbs on antioxidant properties of broilersAntioxidant properties also have a close relationship with the body’s resistance to disease.the contents of glutathione peroxidase(GSH-Px),total superoxide dismutase(T-SOD),and malondialdehyde(MDA)in chicken serum were determined with kits.The results were as follows:(1)At day 15,compared with control group,the content of GSH-Pxand T-SOD were significantly increased in treatment groups(P<0.05),the content of MDA decreased significantly(P<0.05).(2)At day 30,compared with the control group,the contents of GSH-Px and T-SOD in treatment groups were significantly increased(P<0.05),and the contents of MDA were significantly reduced(P<0.05).The results showed that the contents of GSH-Px and T-SOD in serum of broilers were increased and the accumulation of MDA was decreased,which enhanced the antioxidant performance of broilers.Conclusions: Based on the results of growth performance,immune properties,and oxidation resistance,2% the six kinds of Chinese herbal feed additives(radix isatidis,common cnidium fruit,astragalus root,duhuo,dangshen and Chinese angelica were mixed at the ratio of 3:1:3:1:2:2)was added in the broiler diet,after being raised for 30 d,the growth of broilers could be promoted,the consumption of feed was decreased,and poultry disease resistance was enhanced. |
PDF Full Text Request