Effects of polysaccharide of Atractylodes macrocephala Koidz combined with microecological preparations on growth performance and serum hormone levels of pigs

Introduction

There is growing concern about the potential threat to human health and the environment posed by the misuse of antibiotics in livestock and poultry farming. Compared with antibiotics, the use of plant polysaccharides and microecological preparations in livestock and poultry is safer, does not cause resistance problems, and does not have a negative impact on the environment, and the combined use of the two is currently receiving attention. However, due to a variety of reasons, the application effect of microecological preparations is not stable0. Atractylodes macrocephala Koidz polysaccharide is an extract from the roots and stems of Compositae. Due to the complexity of the active components in the plant, the effect is not stable enough. Therefore, the study of the synergistic effect of microecological preparation and polysaccharide is the key to achieve the microecological balance and realize the wide application of both. At present, many research results support that the combined application of plant polysaccharides and microecological preparations can promote animal growth, improve animal immunity, and improve animal hormone levels. Wu Liyang [5] found that the combined application of achyranoba polysaccharide and microecological preparations could promote the growth of pigs, and improve the immunity and hormone levels of pigs. Yang Yuanyou et al. and Zhang Xi et al. [6,7] showed that the combined application of astragalus polysaccharide and complex probiotics could improve the survival rate of nurseries pigs, promote the growth of pigs, enhance the immune system and improve intestinal health. Wang Hongling et al. [8] found that the combined application of 0.2% compound microecological preparation and 2.5% astragalus polysaccharide could enhance the growth performance of broilers, significantly increase the average daily gain, reduce the ratio of feed to gain, improve the structure of intestinal flora and enhance the immunity of broilers.

Yang Ying et al. [9] showed that Yupingfeng polysaccharide compound microecological preparation could promote the growth and development of grass carp and improve the intestinal microbial balance of grass carp. These cases provided theoretical support for the combined use of polysaccharides and microecological preparations of atractylodes macrocephala Koidz. The purpose of this experiment was to study the effects of polysaccharide of atractylodes macrocephala Koidz, microecological preparation and their combined use as "green feed additives" added to the basic diet of pigs, paying attention to the feeding effects of pigs at different physiological stages, and exploring the effects of these additives on growth performance and serum hormone, physiological and biochemical levels of pigs during growth and fattening period. In order to provide a theoretical basis for widely used in pig production. In addition, the long-term use of these additives in the healthy breeding of pigs as green, healthy and effective growth promoters for livestock and poultry has important market practical significance and broad market prospects.

Materials and Methods

Test materials

The microecological preparation is provided by Jinseifu (Beijing) Biotechnology Co., LTD. It contains Bacillus subtilis producing antimicrobial peptide, and the total number of viable bacteria per gram reaches or exceeds 1.0×108cfu. The polysaccharide of atractylodes macrocephala Koidz was supplied by Shaanxi Senyuan Biotechnology Co., LTD., and the polysaccharide content was 30%.

Experimental design

A total of 120 weaned piglets with good health and body weight of (7±0.46) kg were selected as the study subjects and randomly divided into 5 The experiment was divided into 3 stages, during which the experiment was conducted according to daily feeding management, and the experiment was divided into 3 stages according to pig weight, including nnursing stage, growth stage and fattening stage. The pre-test lasted for 6 days and the formal experiment lasted for 148 days. The corresponding basal diets were shown in Table 2.

Determination indexes and methods

Determination of production performance

During the test, each test pig was weighed on an empty stomach every day, and the feed amount and remaining amount were recorded daily.

Average daily feed intake = total feed consumption per pig/test days Average daily gain = (final weight of test pig-initial weight of test pig)/test days; Feed to meat ratio = average daily feed intake/average daily gain.

Determination of serum hormone levels

The day before the end of the experiment, the subjects were stopped from providing food and fasting for 12h. In each replicate, 2 pigs were randomly selected to collect blood from the anterior vena cava, and the supernatant (serum) obtained after centrifugation was placed in the centrifuge tube, the group and date were marked, and the serum was stored in the refrigerator at -20℃. The contents of growth hormone (GH), insulin (INS), insulin growth factor (IGF-Ⅰ) and thyroid hormone (T4) in the serum of the experimental pigs were detected by ELISA kit, and the operation was carried out according to the instruction manual.

Determination of serum biochemical indexes

MindraysBS-420 automatic biochemical analyzer was used to analyze the serum samples of experimental pigs to determine the contents of total protein (TP), albumin (ALB), globulin (GLB), albumin/globulin ratio (A/G), immunoglobulin IgG, IgM, total cholesterol (TC) and triglyceride (TG). The kit was derived from Zhongsheng North Holding Co., LTD., and the operation procedure followed the instruction manual.

Data processing and analysis

The experimental data were sorted by Excel software, oneway ANOVA was performed by SPSS 26.0, and multiple comparisons were performed by Duncans. The results were presented in the form of mean plus or minus standard deviation. When the P-value of the result was less than 0.05, the difference was significant. When the result P-value is greater than 0.05, it means that the difference is not significant.

Results and Analysis 3.1 Effects of different treatment groups on daily gain of pigs

According to the data in Table 3, we can draw the following conclusion: During the nursing phase, the average daily gain level of trial Groups 1, 2 and 3 was increased compared with that of the base diet group. In the growth stage, the daily gain in trial group 1 was significantly higher than that in the basal diet group (p<0.05), and higher than that in the antibiotic group (p>0.05). Compared with the basal diet group, the daily gain of trial groups 2 and 3 had a tendency to increase (p>0.05). At fattening stage, the average daily gain of trial groups 1, 2 and 3 was higher than that of basal diet group, and the daily gain of trial group 1 was higher than that of antibiotic group. In the whole feeding stage, the average daily gain of trial groups 1, 2 and 3 was higher than that of basal diet group, and there was no significant difference compared with antibiotic group (p>0.05). The daily gain level of trial group 1 was higher than that of antibiotic group and trial groups 2 and 3, and the data performance was the best.

Effects of different treatment groups on feed/meat ratio of pigs

Table 3 shows that in the three stages of nursing, growth and fattening, the ratio of feed to meat in test groups 1, 2 and 3 is lower than that in the basal diet group; in the growth and fattening stage, the ratio of feed to meat in test groups 1 and 3 is lower than that in the antibiotic group. Among the three groups of the experiment, the ratio of feed to meat in test group 1 was lower than that in test group 2 and 3 at different stages. In the whole experimental stage, the feed to meat ratio of trial group 1 was decreased by 17.64% compared with the basal diet group and 9.03% compared with the antibiotic group, and the data performance was the best.

Effects of different treatment groups on blood hormone levels of fattening pigs

In this study, we compared the serum levels of four hormones (thyroid hormone T4, insulin INS, insulin-like growth factor IGF-1, growth hormone GH) in each group. The data results in Table 4 showed that compared with the basal diet group at the fattening stage, the serum contents of four hormones in trial groups 1, 2 and 3 showed an increasing trend, and the IGF-1 content in group 1 was significantly increased (p<0.05). The serum IGF-1 content in trial group 1 was higher than that in antibiotic group, but the difference was not significant (p>0.05). Further analysis of the three experimental groups showed that the serum IGF-1 content in trial group 1 was significantly higher than that in trial group 2 (p<0.05), but there was no significant difference between trial group 1 and trial group 3 (p>0.05), and there was no significant difference in INS, T4 and GH contents (p>0.05). 12 Note: In peer data, the same lowercase letters or no letters indicated no significant difference (p>0.05), while completely different lowercase letters indicated significant difference (p<0.05).

Effects of different treatment groups on physiological and biochemical indexes of pigs at fattening stage

According to the data in Table 5, we could find that compared with the basal diet group, the contents of total protein and albumin in other treatment groups had an increasing trend, and globulin content was significantly increased (p<0.05). The contents of IgG and IgM showed an increasing trend, but there were no significant differences (p>0.05). Triglyceride content was significantly decreased (p<0.05), and total cholesterol content was significantly decreased in group 1 (p<0.05).Compared with antibiotic group, the contents of total protein, globulin and IgM in three experimental groups were increased (p>0.05), while the contents of albumin and IgG were not significantly different (p>0.05), and the contents of triglyceride and total cholesterol were decreased (p>0.05). Among the three experimental groups, the contents of total protein, albumin and globulin in group 1 were higher than those in the other two groups (p>0.05), the contents of IgG and IgM in group 1 were higher than those in the other two groups (p>0.05), and the contents of triglyceride and total cholesterol in group 1 were lower than those in the other two groups (p>0.05).

Note:

In peer data, the same lowercase letters or no letters indicated no significant difference (p>0.05), while completely different lowercase letters indicated significant difference (p<0.05).

Analysis and Discussion

It has been found that polysaccharides of Rhizoma atractyloides have various physiological activities [10,11] , including antioxidant, anti-inflammatory and immunomodulatory effects [12,13] . Adding polysaccharide of atractylodes macrocephala Koidz to animal feed can promote the growth and development of animals, improve digestion and absorption [14] , improve feed utilization, and enhance the body's resistance to disease [15] . Microecological preparations can regulate the microbial community in the intestinal tract of animals, improve the utilization rate of feed, improve animal health, and enhance animal growth performance [16][17][18] . The results of this experiment showed that compared with the basal diet group, the daily gain of pigs could be increased, the growth of pigs could be promoted and the ratio of feed to meat of pigs could be decreased by adding white rhizome polysaccharide or microecological preparation alone in the diets of nursing pigs, growing pigs and finishing pigs, although the effect was not as good as that of antibiotic group, but the difference was not significant (p>0.05). The study of Peng Huizhen et al. [19] showed that adding atractylodes macrocephala Koidz crude polysaccharide to the diet could significantly increase the average daily gain and feed reward of animals, while reducing the frequency of diarrhea. Qiao Jiayun [20] reported that the effect of lactobacillus added to the basal diet was better than that of flavomycin added to the diet, which increased the average daily feed intake and average daily gain, and reduced the feed to meat ratio of weaned piglets. These results are consistent with the results of this experiment, indicating that adding polysaccharide of atractylodes macrocephala Koidz or microecological preparations in animal feed can produce significant effects, and can improve the growth and feed utilization efficiency of animals. The results of this study showed that the combined use of microecological preparation and microecological preparation in feed was better than that of microecological preparation or microecological preparation or microecological preparation in feed in increasing daily gain and reducing feed to meat ratio. Cen Lu et al. [21] study showed that piglets fed with probiotics combined with astragalus polysaccharide found that the experimental group had higher daily gain and lower feed to meat ratio than the blank group, indicating that the combined use of microecological preparation and polysaccharide had better effects, which was consistent with the results of this study. This may be related to the improvement of immunity and digestion and absorption of polysaccharide of atractylodes macrocephala Koidz, and the improvement of anti-stress ability of pigs by microecological preparation [22] . The two are mutually beneficial when used in combination.

Effects of different treatment groups on blood hormone levels of finishing pigs

Growth hormone (GH), insulin (INS), insulin growth factor (IGF-Ⅰ) and thyroid hormone (T4) are important indicators [23] [24] . Microecological preparation can interact with the intestinal microorganisms of animals, affect the function of their endocrine growth axis, and then affect the stability of the endocrine system and growth regulation function, and then promote more effective nutrient absorption and utilization, and promote the growth and development of animals. Zhu Xiao [25] confirmed this by studying the effects of bacillus bacillus on hypothalamus, pituitary and target organs in mice.Plant polysaccharides and microecological preparations may directly or indirectly promote the secretion and signal transduction of GH, INS, IGF-Ⅰ and T4 by regulating metabolic pathways or by affecting the function of the neuroendocrine system, and then promote cell growth, proliferation and protein synthesis to promote body growth. The results of this experiment showed that the addition of microecologic preparation alone or the combination of polysaccharide and microecologic preparation could contribute to the increase of the content of 4 hormones in pig serum, which was consistent with the results of growth performance. It is worth noting that the concentration of growth hormone and the growth rate of the body may not be consistent in different animals [26] . The results obtained by Ni Yaodi et al. [27] showed that the growth rate of experimental chickens eating the feed supplemented with microecological preparations was significantly increased, but the plasma growth hormone content showed a decreasing trend, which was contrary to the conclusion obtained by Chen Qinghua and this experiment. This may be because growth hormone acts through specific receptors on cell membrane, and there are breed differences among different animals. Some studies have shown that growth hormone receptors in rabbit and pig liver can be up-regulated, while growth hormone receptors in poultry liver can be down-regulated [28] .

Effects of different treatment groups on serum biochemical indices of finishing pigs

Total protein (TP), albumin (ALB), glob ulin (GLB) and albumin/globulin ratio (A/G) are commonly used to evaluate the nutritional status, liver function and immune function of animal proteins. A/G ratio close to 1 is normal, and there are no abnormal results in the five groups. Immunoglobulin IgG and IgM have the function of maintaining the body's immune balance and resisting pathogens. High levels of triglycerides and total cholesterol are associated with an increased risk of cardiovascular disease. The results of this experiment showed that adding rhizoma polysaccharide or microecological preparations, alone or in combination, increased total protein, albumin, globulin, IgG, IgM, triglycerides, and cholesterol levels in experimental pigs. In summary, the three experimental groups outperformed the antibiotic group. Xie Yali et al. [29] found that adding polysaccharide from Niudali to pig feed reduced triglyceride and cholesterol levels. Du Hongming et al. [30] demonstrated that adding yeast or lactic acid bacteria to pig diets increased total protein (TP) and albumin (ALB), consistent with this study's findings. Plant polysaccharides and microecological preparations may improve intestinal flora balance, promote nutrient absorption, regulate protein synthesis and breakdown, and enhance liver metabolism, thereby affecting total protein, albumin, and globulin levels. They also improve albumin's ability to transport cholesterol, enhancing immune capacity and lowering cholesterol levels. Additionally, these preparations can regulate the immune system, influencing immunoglobulin synthesis and secretion, promoting thyroid hormone transport, thus enhancing immunity and improving growth performance.

Conclusions

In the stages of pig nursing, growth and fattening, the diet supplemented with microecological preparations or polysaccharide of atractylodes macrocephala Koidzs alone, or both, can improve the growth performance of pigs, and the combined use of the two agents has the best effect during the whole experiment period, and there is no significant difference with antibiotics. In the fattening stage, the contents of IGF-1, T4 and GH in serum could be increased by the combination of microecological preparation and microecological preparation in the diet. The contents of total protein, albumin, globulin and immunoglobulin IgG and IgM, and the levels of triglyceride and total can be increased by adding microecological preparation and polysaccharide or the combination of the two in pig feed. There was no significant difference in the effect compared with the antibiotic group.

Conflict of Interest Not available

Financial Support

References

1. Xia XP. Strategy analysis of antibiotic substitution in animals [J]. China Poultry Guide. 2019;41(02):38-40.
2. Guangzhou: South China Agricultural University, 2020.
3. Huang Z Y, Deng G Q, Liang Y W, et al. Research and application of microecological preparations in livestock production [J]. Chinese Journal of Livestock Ecology. 2023;11(44):92-96.
4. Zhao Y F, Wang Y Z. Effects of Rhizoma atractyloides, micron Atractyloides and Rhizoma atractyloides polysaccharides on growth performance, intestinal morphology and microecoflora of weaned piglets [J]. Animal Health. 2015;51(1):65-69.
5. Wu L Y. Effects of microecological preparations and Achyranthosa polysaccharide on growth performance and meat quality of pigs [D]. Changsha: Hunan Agricultural University, 2011.
6. Yang YY, He CL. Effects of Astragalus polysaccharides and complex probiotics on survival rate of nursery pigs [J]. Pig Science. 2019;41(02):85-87.
7. Zhang X, Liu G X, Sun Y H, et al. Effects of Astragalus polysaccharides and compound probiotics on survival rate and diarrhea rate of nursery pigs [J]. Foreign Animal Science (Swine and Poultry). 2023;43(03):50-52.
8. Wang HL, Liu DD, Jiang SW, et al. Effects of compound microecological preparation and Astragalus polysaccharides on growth performance, intestinal flora and immune function of broilers [J]. Feed Industry. 2014;35(06):10-14.
9. Yang Y, Yang ML, Yi MY, et al. Effects of Yupingfeng polysaccharide compound microecological preparation on growth and intestinal flora of grass carp. Feed Res. 2023;46(11):66-70.
10. Jiang WW, Feng XH, Wen GH. Research progress on pharmacological effects of polysaccharides from Atractylodes macrocephala Koidz. Hunan Anim Husb Vet Sci. 2023;(05):50-3.
11. Yang ZZ. Effects of Atractylodes macrocephala Koidz polysaccharide on growth performance, serum biochemical indices and intestinal morphology and structure of broilers. Feed Res. 2019;46(12):46-50.
12. Li X, Rao Z, Xie Z, et al. Isolation, structure and bioactivity of polysaccharides from Atractylodes International Journal of Veterinary Sciences and Animal Husbandry https://www.veterinarypaper.com macrocephala: A review. J Ethnopharmacol. 2022;296:115506.
13. Yang H, Wu C, Chen L, et al. Macrocephala polysaccharide induces alterations to gut microbiome and serum metabolome in constipated mice. Microb Pathog. 2023;178:106084.
14. Kai L, Zong X, Jiang Q, et al. Protective effects of polysaccharides from Atractylodes macrocephala Koidz against dextran sulfate sodium-induced intestinal mucosal injury in mice. Int J Biol Macromol. 2021;195:142-51.
15. Guo S, Li W, Chen F, et al. Polysaccharide of Atractylodes macrocephala Koidz regulates LPSmediated mouse hepatitis through the TLR4-MyD88NFκB signalling pathway. Int Immunopharmacol. 2021;98:107692.
16. Huang ZY, Deng GQ, Liang YW, et al. Research and application of microecological preparations in livestock and poultry production. Chin J Livest Ecol. 2023;44(11):92-96.
17. Ge QX. Application of microecological preparations in pig production. Mod Anim Sci Technol. 2021;(03):46-47.
18. Li ZK. Effects of microecological preparations on growth performance, meat quality and intestinal flora of growing-finishing pigs [Dissertation]. Nanjing: Nanjing Agricultural University, 2022.
19. Peng HZ, Li LL, Zhang B, et al. Effects of crude polysaccharide of Rhizoma albus on performance and blood biochemical indices of weaned piglets. J Hunan Agric Univ Nat Sci. 2006;32(6):648-651.
20. Qiao JY. Effects of Lactobacillus on growth, metabolism and immune function of weaned piglets [Dissertation]. Zhengzhou: Henan Agricultural University, 2005.
21. Cen L, Chen L, Zhang XL, et al. Study on clinical improvement of growth performance of piglets by probiotics and Astragalus polysaccharides. China Anim Husb Vet Med. 2009;36(12):17-19.
22. Chen QH, He JH, Liu ZY, et al. Effects of Achyranthes polysaccharide on intestinal microbes and intestinal mucosal morphology of piglets. J Hunan Agric Univ Nat Sci. 2007;33(6):723-726.
23. Jiang L, Guo WT, Chen ZM, et al. Effects of Chinese herbal feed additives on immune function, antioxidant capacity and growth hormone levels of finishing pigs. Chin J Vet Sci. 2019;52(01):120-127.
24. Tao X, Gu YR, Liang Y, et al. Study on developmental changes of growth hormone (GH) and growth hormonereleasing hormone (GHRH) in pig serum. Chin J Anim Husb Vet Med. 2015;42(12):3288-3293.
25. Ya'an: Sichuan Agricultural University, 2007.
26. Yang JT, Cheng X, Chen HW, et al. Research progress on immunomodulatory mechanism of polysaccharides of Rhizoma albus. Chin J Vet Med. 2018;52(6):80-92.
27. Ni YD, Li RW, Zhang QR. Effects of microecological preparations on blood hormone levels in broilers. J Chin Vet Med. 2004;(6):52-53.
28. Wu LY. Study on effects of microecological preparations and Achyranthes polysaccharide on growth performance and meat quality of pigs [Dissertation]. Changsha: Hunan Agricultural University, 2011.
29. Xie YL, Sun RP, Liu GL, et al. Effects of bovine dendropolysaccharide on growth performance, serum biochemical indices, immune indices and intestinal flora of Hainan pigs during fattening period. Feed Res. 2019;46(07):27-33.
30. Du HM, Wang XD, Wang XL, et al. Effects of different probiotic cultures on growth performance, immune function and blood biochemical indexes of weaned piglets. Chin J Vet Med. 2017;37(07):1379-1384.