What Is the Use of Rhodiola Rosea in Animal Feeding?

Rhodiola rosea, also known as the “rose Rhodiola”, is a perennial herb in Crassulaceae. It has the beautiful names “Oriental magic herb”, “plateau ginseng” and “snow mountain immortal herb”[1-2]. Rhodiola rosea is mainly distributed in high-altitude areas of Europe, Asia, and North America[3-4]. China has more than 70 species of Rhodiola rosea[5]. Rhodiola rosea was first recorded in the “Four Medical Classics” and is a dual-purpose medicinal and edible plant. Its roots, stems and leaves can all be used in medicine, but the rhizome is the main ingredient [1,6]. In traditional medicine, Rhodiola rosea is classified as a superior herb. It has a sweet, bitter and astringent taste and a cooling nature. It enters the lungs and heart channels and has the effects of nourishing the lungs, clearing heat and tonifying the vital energy [7].

In clinical practice, it is often used to treat diseases such as weak body due to Qi deficiency, leucorrhea, diarrhea, chills after illness, shortness of breath and fatigue, and cough due to lung heat [8]. Modern medical research has found that Rhodiola rosea is rich in pharmacologically active ingredients and has functions such as anti-oxidation [9-10], anti-inflammation [11], anti-fatigue [12] and anti-hypoxia [13]. In animal production, Rhodiola rosea can improve animal production performance [14-16], improve the quality of livestock products [17-18] and the economic benefits of farming [19], and has high application value in livestock and poultry production. This paper reviews the active ingredients, biological functions and application of Rhodiola rosea in animal production, intending to provide a reference for the further application of the Chinese herbal medicine Rhodiola rosea in the healthy breeding of poultry.

1 Active Ingredients of Rhodiola Rosea

1.1 Rhodiolosides

Rhodiolosides are the main pharmacologically active ingredients in Rhodiola plants. They have a relative molecular mass of 300, are colorless needle-like crystals, and are easily soluble in water, ethanol and other solvents. The chemical structure of rhodioloside is shown in Figure 1. The content of rhodioloside is used as an important indicator to evaluate the quality of Rhodiola species [20]. In addition to rhodioloside, other glycosides isolated from Rhodiola species include tyrosol, sprucein, isoquercitrin, and diphenylmethylhexahydropyridine [21].

1.2 Rhodiola Polysaccharide

Rhodiola polysaccharide is a natural compound composed of multiple monosaccharides linked by glycosidic bonds [2]. It appears as a reddish-brown fine powder, viscous, and very soluble in water. The chemical structure of rhodiola polysaccharide is shown in Figure 2. Studies have found that monosaccharides such as rhamnose, arabinose, mannose, glucose and galactose are the basic components of rhodiola polysaccharides[22]. At present, the main types of Rhodiola polysaccharides that can be isolated are RCPS, RSA, ST-I, ST-II, ST-III, and JT-I[23-25].

1.3 Rhodiola Flavonoids

Flavonoids are an important active substance in the medicinal Rhodiola rosea plant. They appear as yellow crystals, are optically active, and are poorly soluble in water, but soluble in solvents such as methanol, ethanol, and chloroform. More than 70 flavonoids have been identified in Rhodiola rosea, including luteolin, apigenin, kaempferol, kaempferol-3-O-glucoside, kaempferol-3-O-rutinoside, kaempferol-7-O-glucoside, kaempferol-7-O-rutinoside, kaempferol-3,7-di-O-glucoside, kaempferol-3,7-di-O-rutinoside, kaempferol-3-O-glucoside-7-O-rutinoside, kaempferol-3-O-glucoside-7-O-glucoside, kaempferol-3-O-glucoside-7-O-glucoside, kaempferol-3-O-glucoside-7-O-glucoside, kaempferol-3-O-glucoside-7.

1.4 Other Ingredients

In addition to the main active ingredients mentioned above [28], Rhodiola rosea also contains terpenes, sterols, tannins, organic acids, amino acids, coumarins, essential oils, enzymes, phenylpropanoids, mineral elements, polyphenols, alkaloids and other active ingredients [29-30].

2 The Biological Benefits of Rhodiola Rosea

2.1 Anti-inflammatory

Studies have shown that purified Rhodiola rosea flavonoids can significantly inhibit the secretion of pro-inflammatory factors and block the occurrence of inflammation [31]. Liu Jie et al. [32] found in an animal model of cerebral ischemia-reperfusion injury that rhodiola glycosides inhibited the activation of NLRP3 inflammasomes in cerebral injury through the TLR4/NF-κB signaling pathway, and reduced the expression of NLRP3, apoptosis-related speck-like protein (ASC), cysteine protease-1 (Caspase-1), apoptosis-related speck-like protein interleukin-1β (IL-1β) and interleukin-18 (IL-18) expression, reducing neuronal damage. Yang Lili et al. [33] found that during the treatment of knee osteoarthritis, rhodioloside reduced the production of inflammatory mediators such as IL-1β and interleukin-6 (IL-6) by regulating the expression of the κ-light chain-enhancing (NF-κB) factor of the TLR4 signaling pathway and its downstream key factor nuclear factor-activated B cells, and had a relieving effect on osteoarthritis. Wang Huilian et al. [34] found that in the Raw 264.7 cell inflammation model, the addition of 50 mg/L rhodioloside can reduce the production of adenosine triphosphate (ATP) and reactive oxygen (ROS) production, as well as the protein expression of phosphorylated tyrosine kinase (p-JAK2) and transcription activator 3 (p-STAT3), which has a protective effect against inflammatory damage to Raw 264.7 cells.

2.2 Antioxidant

Zhang Yu et al. [35] found that the scavenging rates of Rhodiola rosea for DPPH and ABTS radicals were 53.24% and 51.35%, respectively. After being processed by twin-screw extrusion, the scavenging rate of Rhodiola rosea for DPPH radicals was significantly enhanced. Zhang Rui et al. [36] used a response surface method to extract the antioxidant substances from Rhodiola rosea, and found that the DPPH scavenging rate of the substance was 89.13%, and the total antioxidant capacity was 1.39 mmol/L.

Zhao Na et al. [37] extracted various chemical components from Rhodiola rosea and used the DPPH free radical to detect its antioxidant properties. It was found that compounds 6, 7, 11, 12, 14, and 17 have strong free radical scavenging abilities, and the scavenging rates are 66.4%, 74.7%, 90.8%, 89.1%, 84.5%, and 86.4%, respectively. In addition, a study found that adding 0.5% Rhodiola Rosea powder and 50 mg/(kg·d) tetramethylpyrazine hydrochloride to the broiler diet can significantly increase the glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) activities in the serum of broilers, and reduces malondialdehyde (MDA) content. It can enhance the antioxidant properties of broilers under hypoxic conditions at high altitudes [38].

2.3 Hypoglycemic

A successful type 1 diabetes model was established in mice by inducing streptozotocin. Rhodiola ethenica extract (REE) was administered by gavage after being treated with 20 kGy of 60Co-γ radiation. It was found to increase mouse body weight and reduce plasma total cholesterol (TC), total triglycerides (TG), and glycosylated hemoglobin (GHb) levels; inhibits α-glucosidase activity and alleviates cardiac, liver, and kidney enlargement; the amount of REE added is positively correlated with the hypoglycemic effect, and 280 mg/kg is the optimal amount [39]. Liu Suxin et al. [40] found that when diabetic mice were given a red ginseng extract by gavage, the blood glucose concentration of the high-dose (1000 mg/kg) red ginseng extract group decreased significantly, and the levels of TC, TG and GHb in the plasma decreased significantly, thereby improving the mice's tolerance to high blood sugar and alleviating the enlargement of the mice's organs.

2.4 Enhances Immunity

Ma Tianyu et al. [41] found that a mixture of Rhodiola extract and codonopsis extract can enhance the proliferation of T lymphocytes and B lymphocytes and the activity of NK cells, thereby enhancing the immunity of mice. Shi Dingcong et al. [42] studied the effect of a red sage cordyceps tablet on mouse immune function and found that it can significantly improve lymphocyte proliferation capacity and the mouse phagocytic index, thereby improving immune function. Li Long et al. [43] found that under hypoxic stress conditions in broilers, the addition of a low dose (0.5%) of red yeast rice to the diet can promote the development of immune organs in broilers, increase the spleen index, bursa index and lymphocyte transformation rate, and increase the concentration of IgA and IgG in the serum. Tan Xiaoyu et al. [44] used cyclophosphamide to prepare an immunosuppressed mouse model. After treating the model with a compound ganoderma lucidum and rhodiola crenulata preparation, the immunity of the immunosuppressed mice was significantly improved, which was related to an increase in the spleen index, peripheral blood leukocyte count, T lymphocyte and B lymphocyte proliferation rate, and cytokine levels.

3   Application of Rhodiola Rosea in Animal Feeding

3.1   Application of Rhodiola Rosea in Pig Feeding 

Ding Yueyun et al.[14] added 0.5% (Group A), 1.0% (Group B), and 1.5% (Group C) Rhodiola rosea to the diet of weaned piglets, respectively. The results showed that compared with the control group, the daily weight gain, daily feed intake and final weight increased by 20.74%, 8.94%, and 6.59%, respectively, compared with the control group, and the feed conversion ratio decreased by 11.32%; the total number of red blood cells, total number of white blood cells and lymphocyte ratio in group C were 20.84%, 23.30% and 19.05%, respectively, higher than those in the control group; and the GSP-Px activity in group C was 10.89% higher than that in the control group. Zhou Fen et al. [45] found that the daily and 19.05%; GSP-Px activity in group C was 10.89% higher than that in the control group. Zhou Fen et al. [45] added 1.0% crushed Rhodiola rosea granules to the diet of weaned piglets exposed to cold stress and found that the blood nitric oxide content of weaned piglets was significantly reduced by 30.65 , and the activities of GSH-Px, the number of white blood cells and red blood cells increased by 17.45%, 24.70% and 30.87%, respectively.

Ren Zili et al. [46] added 6 mg/L red Rhodiola to the semen freezing solution of Tibetan pigs and found that sperm motility, sperm acrosome integrity, and sperm plasma membrane integrity were significantly improved by 35.41%, 15.97%, and 13.81%, respectively, and the DNA methylation level was significantly reduced by 28.07%, which can improve the freezing effect of Tibetan pig semen. Han Xiao et al. [47] found that adding 15% nano-roseroot polysaccharide solution to the frozen semen dilution significantly increased sperm motility, acrosome integrity and plasma membrane integrity, and had a good protective effect on pig semen. Chen Xiaoying et al. [48] found that the addition of 9.0 mg/L rhodiola polysaccharide to pig semen dilution stored at 4 ℃ can improve the antioxidant function of pig semen. In summary, the addition of rhodiola at a certain concentration to pig diets and semen preservation solutions can improve growth performance and antioxidant properties, as well as improve the preservation effect of pig semen and improve semen quality.

3.2 Application of Rhodiola Rosea in Poultry Feeding

Ding Bao'an et al. [49] found that the addition of 9% Rhodiola rosea significantly increased the blood red blood cell count and hemoglobin content of broiler chickens by 2 2.00% and 19.01%, respectively, while the daily weight gain decreased by 2.24 g. The apparent metabolisms of crude protein and crude fat decreased by 13.05% and 10.54%, respectively. Wu Hua et al. [18] found that adding 3% Rhodiola extract to the broiler concentrate increased the slaughter rate and the percentage of complete evisceration to above 89% and 64%, respectively. Cui Xiaona et al. [17] added 0.5%, 1.0%, and 1.5% Rhodiola to the broiler base diet, respectively. The SOD and GSH-Px activities in the serum of each group of broilers increased by 0.93%, 14.09 %, 20.92%, and 15.63%, 19.07%, 27.54%; MDA content was reduced by 11.12%, 13.92%, and 21.61%, respectively. Cui Xiaona et al. [16] added 1.5% Rhodiola rosea to the broiler diet, and the redness value of the chicken meat increased significantly by 4.53%, while the brightness value, yellowness value and tenderness decreased by 4.12%, 14.91% and 7.00%, respectively. Li Shanzheng et al. [38] found that the combined addition of 0.5% Rhodiola rosea powder and 50 mg/(kg.d) salidroside to broiler chickens increased serum GSH and SOD activity and decreased MDA content.

Yin Ruoxin et al. [50] found that adding Rhodiola and other Chinese herbs to the diet of laying hens reduced the cholesterol content of eggs and improved egg yolk quality. Ma Zhi et al. [51] found that adding 8% to 12% compound rhodiola to the diet of laying hens increased egg production and egg quality, and significantly enhanced disease resistance. Li Wenfeng et al. [15] found that adding 10 mg/kg of rhodiola glucoside to the diet of broilers with ascites significantly increased the number of red blood cells, reduced the pulmonary artery systolic pressure and right heart index, and reduced the mortality rate of ascites-affected chickens. Li Long et al. [52] added 0.2% and 0.4% dried powder of Rhodiola extract to the diet of broilers with pulmonary hypertension syndrome. The  mRNA expression was significantly increased, the mRNA expression of ET-1 in the left and right ventricles was significantly decreased, and the mRNA expression of the CaSR gene in the pulmonary artery tissue of broilers was significantly decreased, and finally its expression was maintained to normal levels. In addition, studies have shown that the addition of Rhodiola rosea to broiler diets can enhance the immune function of broilers [43, 53]. Li Long et al. [54] found that adding 0.2% and 0.4% rhodiola to the broiler diet can significantly increase the antibody level of the fowlpox vaccine and enhance the immune function of broilers under hypoxic conditions at high altitudes. Therefore, adding rhodiola to the chicken diet can improve meat quality, enhance antioxidant properties and egg production performance, enhance disease resistance, and reduce morbidity.

3.3 The Application of Rhodiola Rosea in Cattle Feeding 

He Shuling et al. [55] added 0 (control group), 50 (test group II), 100 (test group III) and 200 mg/kg (test group IV) of Tangut Rhodiola rosea to the basic diet of dairy cows. The daily feed intake, daily milk production, milk fat rate, milk protein rate and body condition score were increased by 10.42%, 27.65%, 20.37%, 11.99% and 7.14% respectively compared with the control group; and the lactose rate in group III was the highest, at 5.08%. Nan Xiangbin et al. [56] added 0.02, 0.04, 0.06, 0.08, and 0.10 g/L rhodiola polysaccharide to bovine semen freezing diluent, respectively, and found that the sperm motility, acrosome integrity, and plasma membrane integrity of the 0.06 g/L group were 12.1%, 12. 21%, 10.81%; at the same time, the sperm motility of the 0.06 g/L group was 21.1% higher than that of the control group, the linear movement speed was 5.2 um/s higher, and the linear index was 2.70% higher, indicating that the effect of adding 0.06 g/L of Rhodiola polysaccharide to the frozen dilution of bovine semen was optimal.

Liu Chunlong et al. [57] found that adding 2% compound Rhodiola to the cold-resistant diet of beef cattle significantly increased the weight gain and feed conversion rate of beef cattle, enhanced their immunity, maintained normal endocrine function, effectively alleviated cold stress, and improved their cold tolerance. Zhang Jie et al. [58] found that adding a compound traditional Chinese medicine additive containing 5% to 12% Rhodiola rosea to the diet of beef cattle can promote growth, improve meat quality, enhance the resistance of beef cattle, and reduce mortality. In summary, adding a certain dose of Rhodiola rosea to cattle feed can not only improve their productivity and disease resistance but also enhance the effect of freezing and storing semen.

4 Conclusion

Rhodiola rosea has biological functions such as anti-oxidation, hypoglycemic, anti-inflammatory and anti-viral. Adding Rhodiola rosea to livestock and poultry diets can promote growth, improve meat quality, enhance immunity, and improve the body's antioxidant function under hypoxic conditions. In addition, Rhodiola rosea can also be used as a protective agent for semen freezing to protect semen from stress damage and improve the quality of semen after freezing. However, the form of addition and mechanism of action of Rhodiola rosea in livestock and poultry are still unclear, and further research is needed on the application of Rhodiola rosea in the healthy breeding of poultry.

References:

[1] Yu Tailin. Optimization of extraction technology of active ingredients in Rhodiola rosea and research and development of its yogurt products [D]. Harbin: Heilongjiang Oriental University, 2020.

[2] Hu Ying, Gan Yuxin, Jia Huiping, et al. Research progress on the chemical composition and pharmacological activity of Rhodiola rosea [J]. Qinghai Grassland, 2021, 30(2): 53-56.

[3] Wu M. Extraction, separation and purification of effective components of Rhodiola rosea [D]. Shanghai: Shanghai University of Applied Sciences, 2019.

[4] Wang Y C, Tang X L, Liu D, et al. Evaluation of the biochemical and cytological effects of Rhodiola rosea extract in cosmetics [J]. Science of Daily Chemical Industry, 2018, 41(3): 44-50.

[5] Zhu J, Chen J, Qu X. The physiological functions of Rhodiola rosea and its application in animal production [J]. Guangdong Feed, 2018, 27(8): 39-41.

[6] Wang Jingye, She Yiwen, Wang Hui, et al. Research progress in the clinical application of Rhodiola rosea [J]. International Journal of Traditional Chinese Medicine, 2019(1):95-98.

[7] Yu Dongjian. New progress in pharmacological research and clinical application of Rhodiola rosea [J]. Chinese Medicine Clinical Research, 2020, 12(18):136-138.

[8] Zhang Ruixia, Li Zhanquan, Ma Shuang. Pathogenesis of hypoxic pulmonary hypertension and the role of active ingredients in Rhodiola rosea [J]. Advances in Physiology, 2021, 52(4): 307-310.

[9] Sun Dan. Study on the antioxidant, antimutagenic and anticancer growth inhibitory effects of Rhodiola rosea extract from Changbai Mountain [D]. Yanji: Yanbian University, 2020.

[10] Li Long, Wang Honghui, Liu Suozhu, et al. Effect of Rhodiola rosea on the antioxidant capacity of broilers under hypoxic conditions in the plateau [J]. China Animal Husbandry Journal, 2013, 49(12): 62-64.

[11] Ma Yinghui, Xiong Xin, Li Yue, et al. Extraction process and anti-inflammatory effect of flavonoids from Rhodiola rosea in Changbai Mountain [J]. Chinese Journal of Veterinary Medicine, 2021, 57(11): 56-61.

[12] Tian Hailing, Kang Dongzhou. Comparison of the anti-fatigue effects of Rhodiola rosea from Changbai Mountain and Rhodiola rosea from Tibet in mice [J]. Journal of Yanbian University Medical College, 2022, 45(1): 19-22.

[13] Wang Yibo, Wang Feng, Xiao Zhiyong, et al. Rhodiola rosea capsules improve the ability of mice to tolerate normobaric hypoxia and anti-fatigue effects [J]. Chinese Journal of Pharmacology and Toxicology, 2021, 35(6): 420-426.

[14] Ding Yueyun, Zhou Fen, Zhang Wei, et al. Comparison of the effects of Astragalus, Rhodiola and Angelica on the growth performance and related physiological functions of weaned piglets [J]. Chinese Agricultural Science, 2011, 44(16): 3469-3476.

[15] Li Wenfeng, Li Long, Zhou Bo. Effects of dietary addition of rhodiola extract on growth performance and ascites susceptibility of broilers [J]. Feed Research, 2021, 44(7): 60-62.

[16] Cui Xiaona, Zhao Chao, Ge Aimin, et al. Effects of Rhodiola rosea on growth performance and meat quality of AA broilers [J]. Heilongjiang Animal Husbandry and Veterinary Medicine, 2015(19):214-216.

[17] Cui Xiaona, Zhao Chao, Wang Fuhong, et al. Effects of Rhodiola rosea on the antioxidant properties and flavor composition of AA broiler chicken meat [J]. Heilongjiang Animal Husbandry and Veterinary Medicine, 2015(21): 219-221.

[18] Wu Hua, Zhang Hui, Ma Jixian. Effect of Rhodiola rosea residue on the quality of grazing broiler meat [J]. Heilongjiang Animal Husbandry and Veterinary Medicine, 2010(11):80-81.

[19] Li Long. Effect of Tibetan chicken-derived lactic acid bacteria and Rhodiola rosea on broiler production performance, ascites sensitivity and intestinal function [D]. Yangling: Northwest A&F University, 2015.

[20] Wang Xiaoyan, Li Mei, Shen Zhigang, et al. Research progress on the pharmacological effects of rhodiola glycosides [J]. Chinese Patent Medicine, 2022, 44(12):3932-3935.

[21] Zhang Jiaqi. Extraction and chemical synthesis of rhodioloside from Rhodiola rosea [D]. Tianjin: Tianjin University of Science and Technology, 2018.

[22] Luo Lipan, Zhong Guohui, Tian Fayi, et al. Analysis of monosaccharide composition of polysaccharides from Rhodiola rosea of different origins [J]. Food and Fermentation Industry, 2013, 39(4): 213-215.

[23] Wu Yaru. Research on the extraction, structural characterization and antitumor activity of Rhodiola polysaccharides [D]. Tianjin: Tianjin University of Science and Technology, 2021.

[24] Ma Yinghui, Xiong Xin, Li Yue, et al. Extraction and purification process of Rhodiola polysaccharide components from Changbai Mountain and its immunomodulatory effect [J]. Chinese Journal of Veterinary Medicine, 2021, 57(11): 90-95.

[25] Teng Fei, Gu Yangqin, Shou Panting, et al. Structural characteristics and TLR4 agonist activity of two types of Rhodiola polysaccharides. [J]. Chinese Journal of Pharmacy, 2021, 56(13): 1048-1053.

[26] Liu Xueying, Zhang Ke, Li Huanhuan, et al. Simultaneous determination of seven flavonoids in Rhodiola rosea by HPLC [J]. Journal of Shihezi University: Natural Science Edition, 2020, 38(6): 773-778.

[27] Hu YJ. Optimization of the extraction process and determination of the content of two flavonoids in Rhodiola rosea medicinal materials [J]. Zhejiang Chemical Industry, 2020, 51(9): 51-54.

[28] Chen X, Ding B, Pu SC, et al. Research progress of Rhodiola rosea polysaccharides [J]. Science and Technology Wind, 2018(29): 208-209.

[29] Wang S S. Research on the anti-fatigue activity of Rhodiola rosea extract and its compound [D]. Hefei: Hefei University of Technology, 2017.

[30] Lin X Y, Sun X. Research progress on the anti-aging mechanism of Rhodiola rosea [J]. Chinese Journal of Gerontology, 2018, 38(13): 3299-3300.

[31] Ma Yinghui, Xiong Xin, Li Yue, et al. Extraction process and anti-inflammatory effect of flavonoid components of Rhodiola rosea from Changbai Mountain [J]. Chinese Journal of Veterinary Medicine, 2021, 57(11): 56-61.

[32] Liu J. Anti-inflammatory effect and mechanism of rhodiola glycosides in rat cerebral ischemia-reperfusion injury [D]. Kunming: Kunming Medical University, 2022.

[33] Yang L. Mechanism of Tongluo Zhuyu Fang in treating synovial inflammation of knee osteoarthritis based on TLRs/MyD88 signaling pathway [D]. Beijing: Beijing University of Chinese Medicine, 2018.

[34] Wang Huilian, Zhan Junping, Miao Xiyun, et al. Rhodiola rosea extract affects Raw 264.7 cell inflammation by regulating mitochondria through the JAK2/STAT3 signaling pathway [J]. Chinese Materia Medica, 2022, 45(2): 432-436.

[35] Zhang Y. Study on the effect of twin-screw extrusion operating parameters on the puffing and antioxidant properties of Rhodiola rosea [D]. Yanji: Yanbian University, 2021.

[36] Zhang R, Wang X, Wang YQ, et al. Optimization of the extraction process of effective antioxidant substances from Rhodiola rosea by the response surface methodology [J]. World Traditional Chinese Medicine, 2020, 15(14): 2019-2025.

[37] Zhao N. Study on the chemical composition and antioxidant activity of large-plant Rhodiola rosea [D]. Tianjin: Tianjin Medical University, 2016.

[38] Li Shanzheng, Zhao Yanling, Wang Fucheng, et al. Effect of tianmaizhen combined with rhodiola rosea on serum antioxidant capacity of broilers under hypoxic conditions in the plateau [J]. Plateau Agriculture, 2020, 4(6): 570-574.

[39] Chang Yanqiu. Study on the hypoglycemic effect of irradiated Rhodiola rosea ethanol extract [D]. Yanji: Yanbian University, 2019.

[40] Liu Suxin, Zhang Lu, Cui Chengbi. Study on the hypoglycemic effect of Rhodiola rosea extract [J]. Journal of Yanbian University Agriculture, 2020, 42(2): 21-26.

[41] Ma, Tianyu, Miao Hui, Zhang Shufeng, et al. Effects of a combination of Rhodiola rosea and codonopsis pilosula on immune function in mice [C]//12th National Nutrition Science Conference. Beijing: Chinese Nutrition Society, 2015.

[42] Shi, Dingcong. Research on the enhancement of immunity by Rhodiola rosea and cordyceps sinensis tablets [D]. Changchun: Changchun University of Technology, 2020.

[43] Li Long, Wang Honghui, Liu Suozhu, et al. Effects of Rhodiola rosea on the immune function of broilers under hypoxic conditions in the plateau [J]. China Poultry, 2013, 35(2): 19-21.

[44] Tan Xiaoyu. Effects of compound Ganoderma lucidum and Rhodiola rosea preparations on immune function and anti-fatigue in mice [D]. Yanji: Yanbian University, 2019.

[45] Zhou F, Ding Y, Yin Z, et al. Effects of the Chinese herb Rhodiola rosea on the physiological functions of weaned piglets exposed to cold stress [J]. Anhui Agricultural Science, 2011, 39(12): 7289-7290.

[46] Ren ZL, Song TZ, Zhang J, et al. Effects of Rhodiola rosea polysaccharide on semen quality and sperm DNA methylation after freezing in Tibetan pigs [J]. Chinese Journal of Veterinary Medicine, 2017, 37(7): 1385-1388.

[47] Han X, Dai J, Zhang S, et al. Effect of nano-rhodiola polysaccharide on the cryopreservation of pig semen [J]. Chinese Journal of Veterinary Medicine, 2013, 33(12): 1937-1942.

[48] Chen XY, Ma JY, Song TZ, et al. Study on the effect of Rhodiola polysaccharide on the preservation of Tibetan pig semen at 4 ℃ [J]. Pig Raising, 2016 (6): 33-36.

[49] Ding Bao'an, Li Zhuanjian, Mo Yuanchun. Effect of Rhodiola rosea residue on growth performance, nutrient metabolism and blood indicators of broilers [J]. China Poultry, 2010, 32 (3): 16-19.

[50] Yin Ruoxin, Lian Jinghua, Li Huimin, et al. 1 kind of feed additive for laying hens to improve egg yolk quality: CN104351516A[P]. 2015-02-18.

[51] Ma Zhi. Feed additive for laying hens: CN103284001A[P]. 2016-03-16.

[52] Li Long, Liu Suozhu. Effects of Rhodiola extract on the expression of endothelin-1 and its receptor gene in broiler chickens with hypoxia-induced pulmonary hypertension syndrome [J]. Journal of Northwest Agricultural University, 2019, 28(4): 517-521.

[53] Li Long, Liu Suozhu. Research on the immunomodulatory effect of Rhodiola rosea extract on white blood cells in the peripheral blood of broilers [J]. Heilongjiang Animal Husbandry and Veterinary Medicine, 2019(14):125-127.

[54] Li Long, Qiu Xinxin, Liu Suozhu, et al. Effect of Rhodiola rosea extract on the immune function of broiler chickens under hypoxic conditions in the plateau [J]. Animal Husbandry and Feed Science, 2019, 40(2): 9-11.

[55] He Shuling, Ma Lingfa, Chang Yuwei, et al. Effect of different levels of Tibetan medicine Tanggut Rhodiola on the productivity of Gannan plateau whole milk yak [J]. Chinese Journal of Veterinary Medicine, 2013, 33(9): 1463-1466.

[56] Nan Xiangbin, Wang Gangdi, Li Qingwang, et al. Study on the effect of Rhodiola polysaccharide on the freezing effect of bovine semen [J]. Heilongjiang Animal Husbandry and Veterinary Medicine, 2010 (9): 41-43.

[57] Liu Chunlong, Xia Xiufang, Cao Zhijun, et al. A cold-resistant feed additive for beef cattle: CN102488103B [P]. 2012-06-13.

[58] Zhang Jie. A traditional Chinese medicine additive for beef cattle feed: CN107981051A [P]. 2017-10-21.