Effects of Diet with "Lianteng" Additive of Chinese Herbal Medicine on Blood Biochemical Indexes, Immune and Antioxidant Function of Guangxi Sanhuang Chickens

Sicong LUO, Wenjie LU, Lizhi LU, Fulin WANG, Qian QIN, Cui YANG*, Jiahuang YANG*

1. Guangxi Institute of Animal Science, Nanning 530001, China; 2. Haida Feed Co. Ltd., Dongguan, Guangdong 523147, China

Abstract [Objectives] This trial was conducted to investigate the effects of diet with "Lianteng" additive of Chinese herbal medicine on blood biochemical indexes, immune and antioxidant function of Guangxi Sanhuang chickens. [Methods] 480 Guangxi Sanhuang chickens at the age of 1 d were divided into 4 groups randomly and each group was assigned to 6 replicates with 20 chicks in each replicate; groups A, B and C were treatment groups and fed basal diets with 0.1%, 0.2% and 0.4% of "Lianteng" additive of Chinese herbal medicine respectively during a trial of 70 d. Group D was control group and fed only basal diet. The serum samples were taken from 6 chicks in each group at the age of 21, 35 and 49 d respectively and analyzed for biochemical, immune and antioxidant parameters in serum. [Results] Results from the trial showed that no difference was found in serum content of GLU, TG, TP, TC, and UN in the measurement at the age of 21, 35 and 49 d (P>0.05); however, the content of ALB from groups A and B at 35 d was significantly higher than that from group D (P<0.01), and the ALB content from group B at 49 d was also higher than that from group D (P<0.05); the IgM content at 49 d from group A was lower than that from group D (P<0.05), in addition to this, there was no differences found in the contents of IgG, IgM and IFN-y among groups A, B, C and D during the trial (P>0.05); but the content of IL-2 from groups A and B at 49 d was significantly greater than that from group D (P<0.05); T-AOC from groups A, B and C at 49 d was very significantly higher than that from group D (P<0.01), and the one of group B at 35 d was still obviously higher than that of group D (P<0.05); also at 49 d, the GSH content in groups A and B was much greater than that in group D (P<0.01); T-SOD activity of group B and C at 35 d was distinctly greater than that of group D (P<0.05). [Conclusions] It can be concluded that the addition of 0.2% of "Lianteng" additive of Chinese herbal medicine in diet can increase immune function in a certain extent and promote the antioxidant ability observably for Guangxi Sanhuang chickens.

Key words "Lianteng" additive of Chinese herbal medicine, Guangxi Sanhuang chicken, Immune function, Antioxidant ability

1 Introduction

The long-term and large-scale use of antibiotics has caused serious adverse effects on livestock production and human health in China[1-4]. Traditional Chinese herbal medicine not only has good medicinal functions, but also does not produce adverse risks[5-6]. Therefore, it may become a good substitute for forage antibiotics.

Fructus Forsythiae (Forsythiasuspense) is a kind of commonly used Chinese herbal medicine, which has the functions of clearing heat and removing toxicity, dispersing knot and swelling,etc.[7]. Current studies have also proved that Fructus Forsythiae has antipyretic, antibacterial, anti-inflammatory and other effects, and can be used to treat fever, influenza and other diseases[8]. Sinomenine is the main medicinal component of Caulis Sinomenii, which has good effects on anti-inflammation, analgesia and immune regulation[9]. Indian Trumetflower Seed contains flavonoids, phenols, organic acids and other active substances, which also have anti-inflammatory, antibacterial, antioxidant and anti-viral and other pharmacological effects[10]. The compound preparation composed of Fructus Forsythiae and Caulis Sinomenii has good anti-inflammatory effect[11]. When the ostrich is fed with the Chinese herbal medicine additive composed of Fructus Forsythiae and Caulis Sinomenii, it can promote its growth and reduce the feed-weight ratio and mortality[12]. However, the application of similar Chinese herbal medicine in livestock and poultry has not been reported since then. In this study, Guangxi Sanhuang chicken were fed with 6 kinds of Chinese herbal medicine additives, such as Fructus Forsythiae, Caulis Sinomenii and Indian Trumetflower Seed,etc., and the effects on blood routine, immune and antioxidant performance were observed, so as to provide reference for better alternative feeding antibiotics.

2 Test materials and methods

2.1 Investigational drugs"Lianteng" Chinese herbal medicine additive (hereinafter referred to as "Lianteng" additive) is composed of 6 kinds of Chinese herbal medicine in a certain proportion, such as Fructus Forsythiae, Caulis Sinomenii, Indian Trumetflower Seed,PatriniascabiosaefoliaFisch.etc., which was provided by Guangxi Guixue Pharmaceutical Co., Ltd. After being crushed through 100-mesh sieve, it was bagged for reserve, and when used, it is mixed and fed according to the experimental design proportion.

2.2 Experimental diet and nutrition levelThe basic diet was provided by Guangxi Dafuhua Agriculture and Animal Husbandry Feed Co., Ltd. (the formula is confidential), and the main nutritional levels of the diet can be seen in Table 1.

Table 1 Nutritional level of basal diet %

2.3 Experimental animals, design and feeding management

The experiment was carried out in the chicken experimental base of the Animal Husbandry Research Institute of Guangxi Zhuang Autonomous Region. 480 Guangxi Sanhuang chickens of one day old were provided by Guangxi Jinling Husbandry Group Co., Ltd.; a single factor completely random design was used in this experiment, the experimental chickens were randomly divided into 4 groups, A, B, C and D with 6 replicates in each group and 20 chickens in each replicate; group D was the control group and was only fed the basic diet. In addition, 0.1%, 0.2% and 0.4% "Lianteng" additives were added to the basic diet of three experimental groups, A, B and C groups, respectively, the experiment lasted for 70 d. During the period, the chickens were managed and immunized according to the production routine, the chickens aged from 1 to 21 d were raised in the brooding room, which was equipped with automatic temperature control system; the chickens were fed with the experimental diet at the first day, and were fed at 08:00 and 15:00 every day for free feeding and drinking. During the experiment, except for the diet composition, the other feeding conditions were the same.

2.4 Measurement indexes and methodsOn the 21st, 35thand 49thd of the experiment, 6 chickens (1 chicken/replicate) were randomly selected from each group to collect blood from the inferior wing vein, and the serum was separated and stored at -20 ℃. After that, blood biochemical, immune and antioxidant indexes were determined, including total protein (TP), albumin (ALB), triglyceride (TG), serum glucose (GLU), total cholesterol (TC) and urea nitrogen (UN), which were detected by Guangxi Ruikang Hospital; the contents of interleukin-2 (IL-2), interferon-γ (IFN-γ), immunoglobulin-M (IgM), immunoglobulin-G (IgG), total antioxidant capacity (T-AOC), glutathione (GSH) and the activity of total superoxide dismutase (T-SOD) were determined by Nanjing Jiancheng Bioengineering Institute with the corresponding kits produced by Nanjing Jiancheng Saihao Technology Co., Ltd.

2.5 Data processingSPSS16.0 statistical software was used to process the experimental data and one-way ANOVA analysis. Duncan’s method was used for multiple comparisons, and the results were expressed as mean±standard deviation.

3 Results and analysis

3.1 The influence on serum biochemical indexesThe data in Table 2 showed that although the serum GLU of group A was significantly higher than that of groups B, C and D on the 49thd (P<0.05), there was no significant difference between groups B, C and group D (P>0.05); the ALB content of groups A and B was significantly higher than that of group D on the 35thd (P<0.01), and group B was also significantly higher than that of group D on the 49thday (P<0.05), but there was no significant difference between groups A, C and group D (P>0.05); it can be seen that adding 0.2% "Lianteng" additive to the diet can significantly increase the ALB content of chickens at 35 and 49 d; in addition, there was no significant difference in other serum biochemical indexes between groups A, B, C and D in three different stages (P>0.05).

Table 2 Determination of serum biochemical indexes in experimental chickens

3.2 The influence on serum immune indexesThe data in Table 3 showed that the IgM content of group A was significantly lower than that of group D on the 49th day (P<0.05), but there was no significant difference between group B, group C and group D (P>0.05); on the same 49thday, the IL-2 content in groups A and B was significantly higher than that in group D (P<0.05); however, there were no significant differences in IgG and IFN-Y contents between experimental groups A, B and C and D at 21 and 35 d and at three different stages (P>0.05).

Table 3 Serum immune indexes of experimental chickens

3.3 The influence on serum antioxidant indexesThe data in Table 4 showed that the T-AOC of experimental groups A, B and C had no significant difference compared with that of group D at 21 d (P>0.05), however, at 35 d, the T-AOC of experimental group B was significantly higher than that of group D (P<0.05), especially at 49 d, the T-AOC of experimental groups A, B and C was significantly higher than that of control group D with extremely significant difference (P<0.01). At 21 and 35 d, the GSH content in groups A, B and C had no significant difference compared with that in group D (P>0.05), but at 49 d, the GSH content in groups A and B was extremely significantly higher than that in group D and C (P<0.01). At 21 d, although the T-SOD activity in group B tended to be higher than that in group D, the difference was not significant (P>0.05). However, at 35 d, the T-SOD activity in groups B and C was significantly higher than that in group D, and the difference was significant (P<0.05). At 49 d, the T-SOD activity in group A was significantly lower than that in group D (P<0.05), but there was no significant difference between groups B, C and group D (P>0.05). It can be seen that adding three different levels of "Lianteng" additive to the diet can improve the antioxidant performance of chickens to different degrees, and by comparison, the supplemental level of 0.2% was the best.

Table 4 Serum antioxidant indexes of experimental chickens

3.4 Death of chickens during the experimentThe death of chickens during the experiment was shown in Table 5.

Table 5 Death of chickens during the experiment pcs

According to the death of experimental chickens during the whole experiment, the mortality of chickens in the three experimental groups was lower than that in the control group, especially in groups B and C, which was only 50% of that in the control group D, in addition, the death of group B only occurred before 21 d, and no chickens died after 21 d.

4 Discussion

4.1 Effects of "Lianteng" additive on blood biochemical and immune performance of experimental chickensAdding three levels of "Lianteng" additive to the diet had no significant effect on the main blood biochemical indexes of the experimental chickens, but adding amount of 0.2% can significantly increase the ALB content of chickens at 35 and 49 d, and also obviously increase the serum IL-2 content at 49 d. Serum ALB can not only maintain the colloidal osmotic pressure of body tissues and the integrity of vascular endothelium, but also play an important physiological role by combining with a variety of endogenous and exogenous compounds, in addition, it also has good anti-inflammatory and free radical scavenging effects[13-14]. Moreover, IL-2 is a cytokine produced by activated lymphoid T cells, it can not only promote the proliferation and differentiation of T cells, enhance the activity of T cells and NK cells, but also enhance the immune function of the body by promoting the activation and proliferation of T cells, in addition, it can also induce the production of interferon and the production of auxiliary antibodies. Therefore, the level of IL-2 marks the level of immune function[15-16]. In this study, adding 0.2% "Lianteng" additive to the diet can increase the ALB content of experimental chickens at 35 and 49 d and IL-2 content at 49 d, which indicates that adding 0.2% "Lianteng" additive to the diet can improve the physiological function and immune performance of test chickens to a certain extent.

4.2 Effects of "Lianteng" additive on antioxidant capacity and mortality of experimental chickensIn this experiment, the addition amount of three "Lianteng" additives could significantly increase the T-AOC of experimental chickens at 49 d, in addition, 0.2% supplemental level could significantly increase T-AOC at 35 d, serum GSH content at 49 d and T-SOD activity at 35 d. It can be seen that three different levels of supplementation can improve the antioxidant capacity of experimental chickens to a certain extent, but 0.2% of the amount should be the best. T-AOC of the body is the overall reflection of antioxidant enzyme system and non-enzyme system to free radical metabolism in the body, and it is a kind of display of the level of antioxidant capacity of the body[17-18]. GSH is the most important non-enzymatic antioxidant substance in cells of the body, which can inhibit and scavenge free radicals and peroxides[19-23]. Superoxide dismutase (SOD or T-SOD) can remove superoxide anion in the process of biological oxidation and eliminate the damage of superoxide anion free radicals to the body, so it is considered as the first line of defense of antioxidant system[24]. Therefore, the level of SOD activity can represent the body’s ability to scavenge free radicals[25]. In this study, 0.2% additive level of "Lianteng" can significantly increase the contents of T-AOC, GSH and the activity of T-SOD in serum of experimental chickens, which can prove that 0.2% additive level can improve the antioxidant capacity of experimental chickens. The reason may be related to the bioactive substances contained in various components of Chinese herbal medicine in this additive. Studies have shown that Chinese herbal medicines containing flavonoids, polysaccharides, polyphenols, alkaloids, volatile oils and organic acids can generally improve the T-AOC and SOD activities of broilers, and enhance the antioxidant capacity of chickens[26-30]. Moreover, the additives of "Lianteng" contain one or more such active substances, such as Fructus Forsythiae, Caulis Sinomenii, Indian Trumetflower Seed,P.scabiosaefoliaFisch.,etc.[8,31，9-10]. Therefore, adding "Lianteng" additive to the diet can improve the antioxidant capacity of chickens in different degrees, and the best effect is 0.2%. Perhaps it is also the reason that the mortality of the experimental chickens fed with "Lianteng" additive was lower than that of the control group, especially in group B fed with 0.2% of "Lianteng" additive, the mortality was only 50% of that of the control group, and the mortality only occurred before 21 d, because the effect of the additive gradually improved the antioxidant capacity and immunity of the experimental chickens after 21 d, which improved the disease resistance and reduced the mortality. Therefore, the significant decrease in mortality of experimental chickens in group B may be related to the significant increase in immunity and antioxidant capacity of experimental chickens. However, the results should be further studied.

5 Conclusions

The three supplemental levels of "Lianteng" additive had no significant effect on the main serum biochemical indexes of chickens, but adding amount of 0.2% significantly increased the serum albumin content at 35 and 49 d; adding three levels of "Lianteng" additive to the diet could improve the immune performance and antioxidant capacity of experimental chickens in different degrees; in contrast, the effect of 0.2% supplemental amount was the best.