Effect Of Sodium Humate And Glutamine Addition To The Diet On Growth Performance And Antioxidant Function Of Broiler Chickens

In high density feeding environments,a variety of factors can cause stress in broilers,leading to a decrease in immune function and antioxidant capacity,which in turn affects growth performance and leads to lower economic efficiency.Sodium humate(HNa)is a multifunctional organic weak acid with antibacterial,anti-inflammatory,antioxidant and immunomodulatory properties.Glutamine(Gln)is a non-essential amino acid that has the ability to enhance animal growth performance,improve immune status,increase antioxidant capacity and maintain intestinal barrier function.However,the effects of sodium humate and glutamine on the growth performance,immune response capacity and antioxidant function of broiler chickens have not been reported yet.The aim of this study was to investigate the effects of combined application of HNa and Gln in the diet on growth performance,antioxidant function,immune response capacity and intestinal health of broiler chickens.In this experiment,360 1-day-old broilers(AA chickens)were randomly divided into 4 groups: control group(basal diet),sodium humate group(basal diet+5 g/kg HNa),glutamine group(basal diet+10 g/kg Gln)and combined group(basal diet+5 g/kg HNa+10 g/kg Gln),with 3 replicates of 30 birds each.Blood samples were taken before morning feeding at 21 and 42 days of age respectively,after which the broilers were executed.Growth performance and slaughter performance were calculated and recorded according to the Poultry Performance Nomenclature and Statistical Methods of Measurement.Blood was centrifuged and serum was collected for immunoglobulins,liver function,liver metabolism and other relevant indicators.The liver,spleen,thymus and bursa of Fasciola were taken and weighed for organ index testing.Paraffin sections and HE staining were applied to observe the height of intestinal villi and depth of crypt in jejunum and ileum;enzyme-linked immunosorbent assay(ELISA)was applied to detect changes in immunoglobulin levels;kits were applied to detect indicators related to liver function,liver metabolism,oxidative stress and small intestine digestive enzyme activity;real-time fluorescence quantitative PCR(q PCR)was applied to detect m RNA expression of indicators related to the intestinal barrier The kits were also used to detect the m RNA expression of intestinal barrier-related indicators.The experimental results show that:(1)Compared with the control group,the combined addition of HNa and Gln to the diet significantly increased the body weight of broilers at 21 and 42 days of age,the average daily feed intake of broilers from 1 to 42 days of age and the average daily weight gain of broilers from 1 to42 days of age(P < 0.05);the combined addition of HNa and Gln to the diet significantly increased the half-cleaning rate and full-cleaning rate of broilers at 42 days of age(P < 0.05).(2)The combination of HNa and Gln in the diet significantly increased the spleen index and thymus index of 21-day-old broilers and the bursal index of 42-day-old broilers compared with the control group(P < 0.05).(3)Compared with the control group,sodium humate and the combined group significantly increased the jejunal and ileal villus height,as well as the jejunal villus height and villi ratio of 42-day-old broilers(P < 0.05);(4)Compared with the control group,the combined addition of HNa and Gln to the diet significantly increased the jejunal and ileal catalase(CAT)activity of21-day-old broilers(P < 0.05);compared with the control group,the combined addition of HNa and Gln significantly increased the jejunal and ileal catalase activity of 42-day-old broilers(P < 0.05).HNa and Gln significantly increased the total antioxidant capacity(T-AOC)activity and total superoxide dismutase(T-SOD)activity in the jejunum and ileum of 42-day-old broilers compared to the control group(P < 0.05),and the addition of HNa and Gln to the diet significantly reduced the level of malondialdehyde(MDA)in the ileum of 42-day-old broilers(P < 0.05).(5)The levels of serum immunoglobulin G(Ig G)in broilers at 21 days of age and the levels of serum Ig G in broilers at 21 and 42 days of age were significantly higher in the glutamine group compared to the control group(P < 0.05);the levels of serum immunoglobulin M(Ig M)in broilers at 42 days of age were significantly increased by the combined addition of HNa and Gln to the diet(P < 0.05).(6)The activity of jejunal α-amylase(AMS)was significantly higher in the glutamine group and the combined supplementation group compared to the control group at 42 days of age in broilers(P <0.05).(7)The m RNA expression levels of jejunal occludin(Occludin),occludin(Claudin-1)and tight junction protein(ZO-1)were significantly higher in the glutamine group and the co-added group compared to the control group at 21 days of age(P < 0.05).In summary: the addition of HNa and Gln to the diet can improve the growth performance and resistance to oxidative stress of broilers by increasing the immune level,the activity of antioxidant enzymes,the activity of intestinal digestive enzymes and improving the intestinal barrier.In addition,the combined addition of HNa and Gln is more effective than adding them separately.