Go to Top Go to Bottom
Anim Biosci > Volume 34(12); 2021 > Article
Wang, Luo, Li, Zhang, and Liu: Effect of Salvia miltiorrhiza aerial parts on growth performance, nutrient digestibility, and digestive enzymes in rabbits

Abstract

Objective

This study aimed to investigate the effect of Salvia miltiorrhiza (S.m.) aerial parts as an alternative ingredient on growth performance, nutrient digestibility, and digestive enzymes in growing rabbits.

Methods

Treatments included five tested diets: a control (basal diet), antibiotic (basal diet +enramycin at 5 mg/kg), and S.m. aerial parts powder added at 3.0%, 6.0%, and 9.0% of feed using 300 growing rabbits.

Results

The diets with S.m. aerial parts addition at 9.0% decreased (p<0.05) feed/gain compared to the control, but there were no differences in feed intake and body weight gain. In contrast with the control, the addition of antibiotic increased (p<0.05) digestibility of dry matter, crude protein, energy, fiber, and ash. The herb addition did not cause differences in the digestibility of most nutrients compared to the antibiotic, but fiber digestibility of the herb at 6.0% and 9.0% was lower (p<0.05) than that of the antibiotic. Moreover, the antibiotic and the herb also similarly increased (p<0.05) the activities of duodenal α-amylase, maltase, lipase, and trypsin, compared to the control, and the herb at 6.0% and 9.0% showed a greater (p<0.05) activity of elastase than the dose 3.0%.

Conclusion

The obtained data indicate that S.m. aerial parts can be a potential forage in rabbit’s diet at 9.0% with a beneficial regulation on nutrition and digestion.

INTRODUCTION

Salvia miltiorrhiza (S.m.) is a perennial herbaceous medicinal plant 30 to 80 cm in height. Recently, clinical studies have confirmed that S.m. crude extract or active components had the ability to treat diabetic, cardiovascular, and neurodegenerative diseases [13]. The action mechanism of S.m. relies on the amelioration of oxidative stress by regulating antioxidant systems, such as superoxide dismutase, catalase, and glutathione [4]. The popularity of S.m. phytochemicals lead to a strong market demand and consequent large artificial planted area for obtaining its root while aerial parts including stems, leaves, and flowers are also worthy of investigation.
The significant pharmacological components extracted from S.m. can be mainly divided into two categories: fat-soluble tanshinone compounds and water-soluble salvianolic acids which are representative active ingredients in herbal medicine [5,6]. Given the function against oxidation, inflammation, allergy, and cancer and regulation of tissue repair and regeneration, whether the aerial parts of S.m. can be a forage with a growth-promoting effect in farm animals is unclear. Moreover, no literature reports the relationship between S.m., nutrient digestibility, and digestive enzyme activity.
Therefore, for the exploration of new forage resources and maximum utilization of by-products from the human consumption, the present study aimed to investigate the effect of S.m. aerial parts as an alternative ingredient on growth performance, nutrient digestibility, and activities of digestive enzymes in farm rabbits compared to controls with/without a growth-promoting antibiotic.

MATERIALS AND METHODS

Animal care

The experimental protocol of the present study was approved by the Institutional Committee for Animal Use and Ethics of Henan University of Science and Technology (No. 2018010).

Salvia miltiorrhiza and diets

The S.m. was planted in Funiu mountains in Luoyang of China (112°17′ N, 34°52′ E) and aerial parts were harvested during the last week of flowering, air dried, ground into meal (40-mesh sieve) and added at 3.0%, 6.0%, and 9.0% in diets [7]. The chemical composition of aerial parts of S.m. was listed in Table 1.
The nutrition levels of diets and animal management were referred to Technical Specification for Feeding and Management of Hyla Rabbits (Table 2). All diets were considered as isoenergetic and isonitrogenic and were fed as cold formed pellets (diameter×length, 3.5×8.0 mm) with water content under 14% [8].

Animals and samples

A total of 300 weaned male Hyla rabbits at approximately 35 days old with initial body weight 1,062 g±17.8 (mean±standard deviation) were randomly assigned to 5 groups with 6 replicates of 10 rabbits each. Rabbits per replicate were housed individually in a continuous row cage [9,10] and all replicates were uniformly distributed in the rabbit house to minimize spatial errors. The rabbits had free access to the diet and water and free of medication other than experimental factors. The feeding trial lasted for 28 d after an adjustment period of 5 d. Rabbits and feed in each replicate were weighed weekly. Average daily feed intake (ADFI), average daily body weight gain (ADG), and feed/gain were immediately adjusted when mortality occurred. All rabbits were monitored for general health twice a day throughout the trial.
At 26 to 28 d of the feeding trial, fresh feces from individual rabbits were collected, pooled by replicate, and prepared for the analysis of nutrient digestibility [11]. Care was taken during the collection of fecal samples to avoid contamination from fur and other foreign materials. At 28 d, 5 rabbits per replicate were randomly selected, suffocated by carbon dioxide, and then the duodenum were dissected and cleaned with phosphate-buffered saline (0°C to 4°C) and mucosa samples were collected and stored at −40°C for digestive enzyme assay [12].

Chemical and biochemical analysis

Chemical analysis of proximate nutrients in diets and S.m. aerial parts was carried out according to the method by Liu et al [11]. Total tanshinone compounds and phenolic acids in S.m. were detected according to Pharmacopoeia of China (Volume I, 2015) by high performance liquid chromatography and thin layer chromatography, respectively.
Assay kits from Nanjing Jiancheng Biological Institute (Nanjing, China) were used for the detection of lipase (A054-1-1), α-amylase (C016-2-1), sucrase (A082-2-1), maltase (A082-3-1), trypsin (A080-2-2), and elastase (H198). All samples were carried out in triplicate according to the specifications of kits. The units of enzymes were finally calculated and expressed as per mg of protein in the supernatant of tissue samples to minimize the errors during sample preparation.

Statistics

Data were subjected to analysis of variance and means (n = 6) were separated by Tukey’s-b test at p<0.05 using IBM SPSS (version 23). Statistical unit for growth performance and nutrient digestibility was from the average of 10 rabbits per replicate and intestinal digestive enzymes from 5 anatomic rabbits.

RESULTS

Salvia miltiorrhiza and growth performance

Mortality of rabbits throughout the experiment was <5%, not statistically significant among treatments (data not shown). The diets supplemented with S.m. aerial parts at 3.0%, 6.0%, and 9.0% had no significant effects on ADFI and ADG (Table 3), while the dose at 9.0% decreased (p<0.05) feed/gain by 6.2% compared to the control, but there were no differences among other treatments.

Salvia miltiorrhiza and nutrient digestibility

The antibiotic addition increased (p<0.05) the digestibility of dry matter, crude protein, energy, ADF, NDF, and minerals, compared to the control (Table 4). For S.m. aerial parts, similar results were found with these nutrients except for ADF and NDF which were lower (p<0.05) than the antibiotic but similar to the control.

Salvia miltiorrhiza and digestive enzymes

Significant treatment effects (p<0.05) were found with the activity of α-amylase, maltase, lipase, trypsin, and elastase, except for sucrose (Table 5). Antibiotic supplementation resulted in a higher (p<0.05) enzyme activity than the control group for α-amylase, maltase, lipase, and trypsin. The herb at the three doses and the antibiotic had similar effects on these enzymes, but there were no significant dose effects. For elastase, the antibiotic, and the herb at 6.0% and 9.0% did not increase its activity, and the dose 3.0% exhibited the lowest (p<0.05) activity.

DISCUSSION

Root plants including S.m. are well-known for their root utilization but more than half of photosynthesis products are deposited in aerial leaves and stems which can be a good forage source for herbivores [13]. Especially under artificial planting, aerial parts of root crops have a high yield [5]. In the present study, mowing of S.m. was arranged at the last week of the flowering period that lasts approximate 6 months, thereby leading to less lignification, higher nutritional values reflecting on crude fiber and crude protein and a non-significant negative effect on root growth and quality (data not shown) from the serial pilot studies of authors. The proximate nutrient contents primarily indicate that S.m. aerial parts can be a forage in the rabbit feed.
The S.m. aerial parts at the three doses did not cause differences in ADFI and ADG of rabbits among treatments. Literature showed that tanshinone IIA increased ADG of broilers with pulmonary arterial hypertension [14]; Salvia root improved egg performance of hens [15]; however, salvianolic acid B prevented ADG in high-fat diet-induced obese mice [16]. These inconsistencies in feed consumption and growth by feeding aerial parts, root, or bioactive compounds of S.m. to animals need further studies. Interestingly, the feed efficiency in the herb at 9.0% was greater, demonstrating its beneficially physiological regulation. This may be due to the bioactive components of S.m. because tanshinones and salvianolic acids are capable against oxidative stress and inflammation [3,17]. Furthermore, the comparable ADG between the herb and the antibiotic implies the potential growth-promoting effect of S.m. aerial parts.
In the present study, in contrast with the control, supplementation of the antibiotic and the herb resulted in significant increases in the digestibility of nutrients of rabbits. The improved feed efficiency and nutrient digestibility may also be attributed to health benefits of tanshinones and salvianolic acids of S.m. Indeed, S.m. root improved intestinal barrier integrity, physiological metabolism, and amino acids absorption [18,19]. Paradoxically, in a rodent model, tanshinones and salvianolic acids depressed nutrient deposition and modulated gut microbiota [16,20]. Information is however unavailable about the effect of S.m. aerial parts on the growth performance and nutrient digestion in farm animals. In the present study, significant increases in nutrient digestibility of diets with the herb addition indicate its beneficial regulation on the digestive physiology of rabbits.
Indeed, the activities of digestive enzymes including α-amylase, sucrase, maltase, lipase, and trypsin were increased in diets containing S.m. aerial parts. However, high doses of flavonoids from Salvia chlorolueca aerial parts showed inhibitory effects on α-amylase and α-glucosidase [21]. Similarly, cryptotanshinone or tanshinone IIA from S.m. at 1% inhibited pancreatic lipase activity [22]. Jordan indigenous Salvia spp. extracts depressed gastrointestinal carbohydrate and lipid digestion and absorption [23]. Besides the flavonoid concentration, the underlying reason why the extracted flavonoids and their raw materials showed reverse effects on carbohydrases and lipase deserves further study, and molecular docking studies will be needed to establish whether a direct interaction of the principal constituents of the S.m. with digestive enzymes can be evoked. Importantly, the herb also improved protein digestion, but literature is unavailable about S.m. or its extracts on the activity of proteases, which needs further study. Additionally, with increasing threats from the environment and pathogens, intestinal antioxidant activity of farm animals becomes especially important [2427], whether the dietary aerial parts of S.m. influence intestinal health is also an interesting topic.

CONCLUSION

Supplementation of S.m. aerial parts at the dose 9.0% decreased feed/gain compared to the control. The antibiotic exhibited significant improvement in the digestibility of dry matter, crude protein, energy, fiber, and ash, and similar results were found for the herb for most nutrients except for fiber which was lower than the antibiotic but similar to the control. The antibiotic and the herb had similar effects on the activities of α-amylase, sucrase, maltase, lipase, and trypsin. The results suggest that S.m. aerial parts can be a versatile forage with nutritional and growth-promoting effects on herbivores.

Notes

CONFLICT OF INTEREST

We certify that there is no conflict of interest with any financial organization regarding the material discussed in the manuscript. Liu N is an employee of Luoyang Xintai Agro-pastoral Technology Co., Ltd.

ACKNOWLEDGMENTS

The authors thank the animal keepers of Luoyang Xintai Agro-pastoral Technology and laboratory staff of the Animal Nutrition Group, Henan University of Science and Technology, and all colleagues and students for support in practical work.

Table 1
Chemical compositions of Salvia miltiorrhiza aerial parts (% of dry matter)
Composition Content SD
Dry matter 87.1 2.296
Crude protein 11.7 0.208
NDF 60.2 2.023
ADF 41.3 1.762
Ca 0.14 0.005
P 0.19 0.005
Ash 6.92 0.174
Tanshinones 0.63 0.021
Salvianolic acids 0.74 0.031

SD, standard deviation; ADF, acid detergent fiber; NDF neutral detergent fiber.

Table 2
Ingredients and nutrient levels of basal diet and diets containing Salvia miltiorrhiza aerial parts
Item Basal diet Aerial parts
Ingredient (% as fed)
 Aerial parts 0 3.0 6.0 9.0
 Alfalfa meal 35.0 32.0 31.0 31.0
 Corn 25.0 25.0 25.0 25.0
 Soybean meal 10.0 10.0 10.0 11.0
 Brewers dried grain 15.0 15.0 13.0 11.0
 Wheat bran 10.0 10.0 10.0 8.0
 Premix1) 5.0 5.0 5.0 5.0
Nutrients2) (% of dry matter)
 Crude protein 16.5 16.4 16.1 16.2
 Digestible energy (MJ/kg) 10.53 10.52 10.46 10.37
 Acid detergent fiber 15.7 16.1 16.3 16.8
 Neutral detergent fiber 23.4 24.0 24.2 24.7
 Ash 6.61 6.57 6.63 6.58

1) The premix provided the following per kg of the diet: vit A, 6,000 IU; vit D, 1,000 IU; vit E, 38 mg; Cu, 9 mg; Fe, 50 mg; Mn, 9.0 mg; Zn, 40 mg; dicalcium phosphate, 25 g; NaCl, 4.0 g; Lys, 2.4 g; Met, 1.6 g.

2) Digestible energy was calculated by Chinese Feed Database (version 28, 2017) and others were measured.

Table 3
Effect of Salvia miltiorrhiza aerial parts on the growth performance of rabbits
Item Control Antibiotic Supplemental aerial parts SEM p-value

3.0% 6.0% 9.0%
Initial BW (kg/rabbit) 1.07 1.06 1.07 1.05 1.06 0.049 0.998
Final BW (kg/rabbit) 2.65 2.74 2.66 2.68 2.60 0.057 0.188
ADFI (g/rabbit/d) 164 167 159 160 150 7.786 0.283
ADG (g/rabbit/d) 56.4 60.3 56.8 58.2 55.3 1.633 0.056
Feed/gain (g/g) 2.91a 2.77ab 2.80ab 2.75ab 2.73b 0.082 0.049

SEM, standard error of mean; BW, body weight; ADFI, average daily feed intake; ADG, average daily BW gain.

a,b Means in a row without the same superscript are different, p<0.05.

Table 4
Effect of Salvia miltiorrhiza aerial parts on the nutrient digestibility of rabbits
Item Control Antibiotic Supplemental aerial parts SEM p-value

3.0% 6.0% 9.0%
Dry matter (%) 55.5b 61.3a 55.8b 58.2ab 60.8a 0.731 0.048
Gross energy (%) 54.9b 61.5a 58.1ab 61.2a 61.6a 0.714 0.043
Crude protein (%) 74.2b 82.3a 78.5ab 79.9a 82.2a 1.216 0.046
NDF (%) 39.5b 48.8a 44.0ab 39.7b 41.5b 1.429 0.012
ADF (%) 13.9b 25.2a 22.6a 15.8b 17.3b 2.253 0.005
Ash (%) 38.5c 55.6a 53.4ab 52.6b 59.8a 2.226 0.008

SEM, standard error of mean; NDF neutral detergent fiber; ADF, acid detergent fiber.

a–c Means in a row without the same superscript are different, p<0.05.

Table 5
Effect of Salvia miltiorrhiza aerial parts on the duodenal digestive enzymes of rabbits
Item Control Antibiotic Supplemental aerial parts SEM p-value

3.0% 6.0% 9.0%
α-Amylase (U/mg) 14.0b 19.8a 17.2ab 20.1a 19.9a 0.535 0.038
Sucrase (U/mg) 1.68 1.57 1.58 1.69 1.61 0.058 0.872
Maltase (U/mg) 2.15b 2.47a 2.34ab 2.39ab 2.52a 0.066 0.046
Lipase (U/g) 1.59b 1.72a 1.65ab 1.70a 1.73a 0.034 0.048
Trypsin (U/mg) 3.17b 3.59a 3.21ab 3.53a 3.65a 0.074 0.046
Elastase (U/mg) 0.25a 0.28a 0.20b 0.27a 0.28a 0.011 0.032

SEM, standard error of mean.

a,b Means in a row without the same superscript are different, p<0.05.

REFERENCES

1. Jia Q, Zhu R, Tian Y, et al. Salvia miltiorrhiza in diabetes: A review of its pharmacology, phytochemistry, and safety. Phytomedicine 2019; 58:152871 https://doi.org/10.1016/j.phymed.2019.152871
crossref pmid
2. Ren J, Fu L, Nile SH, Zhang J, Kai G. Salvia miltiorrhiza in treating cardiovascular diseases: A review on its pharmacological and clinical applications. Front Pharmacol 2019; 10:753 https://doi.org/10.3389/fphar.2019.00753
crossref pmid pmc
3. Wu Y, Xu S, Tian XY. The Effect of salvianolic acid on vascular protection and possible mechanisms. Oxid Med Cell Longev 2020; 2020:5472096 https://doi.org/10.1155/2020/5472096
crossref pmid pmc
4. Jung I, Kim H, Moon S, Lee H, Kim B. Overview of Salvia miltiorrhiza as a potential therapeutic agent for various diseases: an update on efficacy and mechanisms of action. Antioxidants 2020; 9:857 https://doi.org/10.3390/antiox9090857
crossref pmc
5. Zeng H, Su S, Xiang X, et al. Comparative analysis of the major chemical constituents in Salvia miltiorrhiza roots, stems, leaves and flowers during different growth periods by UPLC-TQ-MS/MS and HPLC-ELSD methods. Molecules 2017; 22:771 https://doi.org/10.3390/molecules22050771
crossref pmc
6. Jiang Z, Gao W, Huang L. Tanshinones, critical pharmacological components in Salvia miltiorrhiza . Front Pharmacol 2019; 10:202 https://doi.org/10.3389/fphar.2019.00202
crossref pmid pmc
7. Wang J, Lin L, Li B, Zhang F, Liu N. Dietary Artemisia vulgaris meal improved growth performance, gut microbes, and immunity of growing Rex rabbits. Czech J Anim Sci 2019; 64:174–9. https://doi.org/10.17221/162/2018-CJAS
crossref
8. Ding K, Wang J, Liu N, Zhang F. Effect of Artemisia apiacea Hance on growth performance, cecal opportunistic bacteria, and microbicidal peptides in rabbits. R Bras Zootec 2019; 48:e20190118 https://doi.org/10.1590/rbz4820190118
crossref
9. Zhao H, Zhang F, Chai J, Wang J. Effect of lactic acid bacteria on Listeria monocytogenes infection and innate immunity in rabbits. Czech J Anim Sci 2020; 65:23–30. https://doi.org/10.17221/247/2019-CJAS
crossref
10. Zhao H, Zhang F, Chai J, Wang J. Lactobacillus acidophilus reduces Listeria monocytogenes infection by inhibiting mitogen-activated protein kinase genes in growing rabbits. R Bras Zootec 2020; 49:e20200054 https://doi.org/10.37496/rbz4920200054
crossref
11. Liu N, Wang JQ, Gu KT, Deng Q, Wang JP. Effects of dietary protein levels and multienzyme supplementation on growth performance and markers of gut health of broilers fed a miscellaneous meal based diet. Anim Feed Sci Technol 2017; 234:110–7. https://doi.org/10.1016/j.anifeedsci.2017.09.013
crossref
12. Liu N, Wang JQ, Jia S, Chen Y, Wang JP. Effect of yeast cell wall on the growth performance and gut health of broilers challenged with aflatoxin B1 and necrotic enteritis. Poult Sci 2018; 97:477–84. https://doi.org/10.3382/ps/pex342
crossref pmid
13. Abdallah A, Zhang P, Zhong Q, Sun Z. Application of traditional Chinese herbal medicine by-products as dietary feed supplements and antibiotic replacements in animal production. Curr Drug Metab 2019; 20:54–64. https://doi.org/10.2174/1389200219666180523102920
crossref pmid
14. Hu G, Song Y, Ke S, et al. Tanshinone IIA protects against pulmonary arterial hypertension in broilers. Poult Sci 2017; 96:1132–8. https://doi.org/10.3382/ps/pew322
crossref pmid
15. Yang CW, Ding X, Zhao X, Guo YX, Mu AL, Yang ZB. Effects of star anise (Illicium verum Hook. f.), salvia miltiorrhiza (Salvia miltiorrhiza Bge) and ginger root (Zingiber officinale Roscoe) on laying performance, antioxidant status and egg quality of laying hens. Eur Poult Sci 2017; 81:183 https://doi.org/10.1399/eps.2017.183
crossref
16. Li L, Li R, Zhu R, et al. Salvianolic acid B prevents body weight gain and regulates gut microbiota and LPS/TLR4 signaling pathway in high-fat diet-induced obese mice. Food Funct 2020; 11:8743–56. https://doi.org/10.1039/d0fo01116a
crossref pmid
17. Chen X, Wu R, Kong Y, et al. Tanshinone II aattenuates renal damage in STZ-induced diabetic rats via inhibiting oxidative stress and inflammation. Oncotarget 2017; 8:31915–22. https://doi.org/10.18632/oncotarget.16651
crossref pmid pmc
18. Kong XF, Wu GY, Yin YL. Roles of phytochemicals in amino acid nutrition. Front Biosci 2011; 3:372–84. https://doi.org/10.2741/s157
crossref
19. Wang K, Yang Q, Ma Q, et al. Protective effects of salvianolic acid A against dextran sodium sulfate-induced acute colitis in rats. Nutrients 2018; 10:791 https://doi.org/10.3390/nu10060791
crossref pmc
20. Cai H, Su S, Li Y, et al. Danshen can interact with intestinal bacteria from normal and chronic renal failure rats. Biomed Pharmacother 2019; 109:1758–71. https://doi.org/10.1016/j.biopha.2018.11.047
crossref pmid
21. Asghari B, Salehi P, Sonboli A, Ebrahimi SN. Flavonoids from Salvia chloroleuca with α-amylsae and α-glucosidase inhibitory effect. Iran J Pharm Res 2015; 14:609–15.
pmid pmc
22. Marrelli M, Grande F, Occhiuzzi MA, Maione F, Mascolo N, Conforti F. Cryptotanshinone and tanshinone IIA from Salvia milthorrhiza Bunge (Danshen) as a new class of potential pancreatic lipase inhibitors. Nat Prod Res 2021; 35:863–6. https://doi.org/10.1080/14786419.2019.1607337
crossref pmid
23. Kasabri V, Afifi FU, Abu-Dahab R, et al. In vitro modulation of metabolic syndrome enzymes and proliferation of obesity related-colorectal cancer cell line panel by Salvia species from Jordan. Rev Roum Chim 2014; 59:693–705.

24. Liu N, Ding K, Wang JQ, Jia SC, Wang JP, Xu TS. Detoxification, metabolism, and glutathione pathway activity of aflatoxin B1 by dietary lactic acid bacteria in broiler chickens. J Anim Sci 2017; 95:4399–406. https://doi.org/10.2527/jas2017.1644
crossref pmid
25. Liu N, Deng X, Liang C, Cai H. Effect of broccoli residues fermented with probiotics on the growth performance and health status of broilers challenged with Clostridium perfringens. Braz J Poult Sci 2018; 20:625–32. https://doi.org/10.1590/1806-9061-2018-0741
crossref
26. Wang J, Lin L, Jiang Q, Huang WL, Liu N. Probiotics and clay detoxifier protected growth performance and intestinal barrier of lambs fed diet contaminated with aflatoxin B1 . Indian J Anim Sci 2019; 89:658–62.

27. Shi H, Shi H, Li Y, Liu N. Effect of lactic acid bacteria on growth performance, oxidative status and infectious parameters induced by Listeria monocytogenes in broilers. Eur Poult Sci 2020; 84:316 https://doi.org/10.1399/eps.2020.316
crossref


Editorial Office
Asian-Australasian Association of Animal Production Societies(AAAP)
Room 708 Sammo Sporex, 23, Sillim-ro 59-gil, Gwanak-gu, Seoul 08776, Korea   
TEL : +82-2-888-6558    FAX : +82-2-888-6559   
E-mail : animbiosci@gmail.com               

Copyright © 2021 by Animal Bioscience.

Developed in M2PI

Close layer
prev next