Next Article in Journal
Microplastic Interactions and Possible Combined Biological Effects in Antarctic Marine Ecosystems
Previous Article in Journal
Equine Stomach Development in the Foetal Period of Prenatal Life—An Immunohistochemical Study
 
 
Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
Journals
Animals
Volume 13
Issue 1
10.3390/ani13010160
animals-logo
Submit to this Journal Review for this Journal Propose a Special Issue
► Article Menu

Article Menu

share Share announcement Help format_quote Cite question_answer Discuss in SciProfiles thumb_up
...
Endorse textsms
...
Comment
first_page
settings
Order Article Reprints
Font Type:
Arial Georgia Verdana
Font Size:
Aa Aa Aa
Line Spacing:
Column Width:
Background:
Article

Inulin and Chinese Gallotannin Affect Meat Quality and Lipid Metabolism on Hu Sheep

by
Zhaohua He
1,
Long Cheng
2,
Shaobin Li
1,
Qiaoling Liu
1,
Xue Liang
1,
Jiang Hu
1,
Jiqing Wang
1,
Xiu Liu
1 and
Fangfang Zhao
1,*
1
Gansu Key Laboratory of Herbivorous Animal Biotechnology, Faculty of Animal Science and Technology, Gansu Agricultural University, Lanzhou 730070, China
2
Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Dookie College, VIC 3647, Australia
*
Author to whom correspondence should be addressed.
Animals 2023, 13(1), 160; https://doi.org/10.3390/ani13010160
Submission received: 29 November 2022 / Revised: 26 December 2022 / Accepted: 29 December 2022 / Published: 31 December 2022
(This article belongs to the Section Small Ruminants)
Browse Figures
Review Reports Versions Notes

Abstract

:

Simple Summary

The identification of new and beneficial alternatives to antibiotics is of great value in ruminant farming. The combined addition of inulin and Chinese gallotannin to the diet could reduce the content of saturated fatty acids in mutton while increasing the content of unsaturated fatty acids. Besides, these supplements could also enhance the energy and lipid metabolism of Hu sheep, ultimately improving mutton quality and production performance. Thus, sheep producers are encouraged to consider using these dietary supplements to support better mutton production.

Abstract

The aim of this study was to investigate the impacts of inulin and Chinese gallotannin on the meat fatty acids and urinary metabolites in sheep. Twenty-four healthy (25.80 ± 3.85 kg) weaned Hu lambs of approximately 4.5 months old were equally divided into four groups: control group (basal diet), treatment group I (basal diet + 0.1% inulin), treatment group II (basal diet + 0.1% inulin + 2% Chinese gallotannin), and treatment group III (basal diet + 0.1% inulin + 2% Chinese gallotannin + 4% PEG). The contents of myristic acid (C14:0) and palmitic acid (C16:0) were found to be lower in treatment group II than in the control group (p < 0.05). Moreover, the palmitoleic acid (C16:1) content in treatment group II was notably higher than that in the control group (p < 0.05), while the elaidic acid (C18:1n9t) content in treatment group II was higher than that in other groups (p < 0.05). Besides, the linoleic acid (C18:2n6c) content was higher in the treatment II and control groups than in the treatment I and III groups. Furthermore, compared with the control group, both 4-pyridoxic acid and creatinine in treatment groups I and II were upregulated (p < 0.05), while other metabolites, such as nicotinuric acid, l-threonine, palmitic acid, and oleic acid, were drastically downregulated (p < 0.05). These differential metabolites were found to be mainly involved in nicotinate and nicotinamide metabolism (ko00760), vitamin B6 metabolism (ko00750), and the fatty acid biosynthesis pathway (ko00061). It is concluded that the combination of inulin and Chinese gallotannin in the diet could improve the energy and lipid metabolism of sheep, which may improve both mutton quality and production performance.

1. Introduction

Misuse of feed additives in ruminant production reduces safety and increases environmental pollution in ruminant husbandry. Therefore, there is increased interest in the identification of alternatives to antibiotics, especially in the ruminant production research community [1].
Inulin (C17H11N5), an oligofructose, is widely distributed in over 36,000 plant species such as roots of chicory (15–20%), burdock (3.5–4%), salsify (4–11%), and garlic (9–16%) [2]. Nowadays, most inulin is produced from chicory roots [3,4]. Due to its solubility and capability to alter blood sugar in ruminants, as well as influencing lipid metabolism and mineral absorption, inulin has been approved for use in animal feeds and medications in the USA, Japan, and Europe [5,6]. Recent studies have shown that inulin may improve rumen fermentation, microbial balance, and growth performance in beef cattle [7]. Further, it is considered that inulin can act in combination with other additives (such as inactivated Bacillus subtilis, magnesium oxide, and polyphenol-rich pomegranate extracts) and may have additional beneficial effects on the livestock, such as improving immunity [8], regulating sugar and lipid metabolism [9], and reducing endotoxemia [10].
Chinese gallotannin (C76H52O46) is derived from the Chinese gallnut. Chinese gall is an important Chinese herbal medicine, and its main bioactive component is a hydrolyzable tannic acid (TA), gallotannins [11]. It has been reported that TA has biological functions, including anti-inflammatory, antioxidant, antibacterial, and antiviral properties [12,13]. As a hydrolyzed tannin, Chinese gallotannin has significant potential to be used in animal production, due to its high yield from gallnut production [14]. Moreover, low to moderate tannin intake by ruminants can also contribute to reduced CH4 emissions, which may enhance the environmental protection goals of the livestock farms [15]. However, excessive tannins intake can have deleterious effects on animals, including reduced food intake and adverse effects on feed digestibility [16]. To minimize the potentially negative effects of tannins, polyethylene glycol (PEG, HO(CH2CH2O)nH) is commonly used as a tannin adsorbent, as it is known to decrease the adverse effects of anorexia in ruminants induced by excessive tannin intake [17,18].
Previous studies have concluded that metabolomics can provide a wealth of information for animal production and health evaluation. Metabolomic analyses can be conducted on a wide range of biological samples, including blood [19], muscle [20], urine [21], feces [22], and intestinal contents [23]. Since inulin is known to interact beneficially with other feed additives for livestock, we speculated that there may be an interactive and beneficial effect between inulin and Chinese gallotannin on animal health and production as both metabolism and meat fatty acids may affect the meat quality [24]. Thus, the present study investigated the interactive effects of inulin and Chinese gallotannin in the diets of Hu sheep, focusing specifically on the fatty acid composition of the meat and urine metabolites.

2. Materials and Methods

The animal experiments were conducted at Baiyin Kang Rui Sheep Breeding Co., Ltd., Gansu, China. All samples were gathered in strict accordance with the code of ethics approved by the Animal Welfare Committee of the College of Animal Science and Technology of Gansu Agricultural University (approval number: GSAU-2-th-AST-2021-001).

2.1. Experimental Animals and Sample Collection

Twenty-four healthy weaned and uncastrated Hu male lambs (approximately 4.5 months old) with similar body weights (25.80 ± 3.85 kg) were randomly selected from the lamb flock and divided into four groups using randomized block design: control group (basal diet, n = 6), treatment group I (basal diet + 0.1% inulin, n = 6), treatment group II (basal diet + 0.1% inulin + 2% Chinese gallotannin, n = 6), and treatment group III (basal diet + 0.1% inulin + 2% Chinese gallotannin + 4% PEG, n = 6). The weaning age for these lambs is around 2 months old. Inulin (purity > 95%) was purchased from Baiyin Rui Sheng Bioengineering Co., Ltd., Baiyin, China; Chinese gallotannin (purity 50–52%) was purchased from Qingdao RBT Biotechnology Co., Ltd., Qingdao, China; PEG was purchased from Tianjin BAISHI Chemical Industry Co., Ltd., Tianjin, China. All sheep were kept in metabolic cages (1.2 m × 1.5 m) individually, were fed twice a day (08:00 am and 17:00 pm), and accessed water freely.
The study took 75 days including a 15-day adaptation period and a 60-day trail period. Daily feed intake was determined based on the difference between offered and residual feed to calculate the dry matter intake (DMI). The body weights (BW) of the individual sheep were measured monthly, and the total weight gain was calculated as the difference between the initial and final BWs. The feed conversion ratio (FCR) and average daily gain (ADG) were determined cumulatively through the collected data. At the end of the measurement period, a urine sample was collected for lipid metabolism analysis: urine samples were collected on the morning of 60td day of the feeding experiment, and the collection device was made according to Kowalczyk et al.’s (1996) description [25]. We transferred the urine to a 50 mL sterile cryopreservation tube immediately after urination Then, urine samples were stored at −80 °C for later analysis. The live weight (LW) of these sheep was determined before slaughter. Sheep were slaughtered humanely following the Islamic practice. The longissimus dorsi muscles were collected after slaughter and used to determine the fatty acid contents.

2.2. Basal Diet

The dietary formula was designed in accordance with the Chinese mutton sheep feeding standard (NY/T 816-2004), and the nutritional levels of the four groups were kept the same (Table 1).

2.3. Measurement of Muscle Fatty Acids

Muscle samples were preprocessed as previously described [26]. The surface fat of the meat samples was removed, and the samples were ground in a mortar with liquid nitrogen. One gram of the ground material was then placed in a 15 mL centrifuge tube, and 0.7 mL of KOH solution at a concentration of 10 mol/L and 5.3 mL of anhydrous methanol (analytical methanol, for chromatography) were added, respectively. The samples were placed in a thermostat water bath at 55 °C for 1.5 h, with shaking for 5 s per 20 min, and were then removed and cooled to below room temperature under tap water after the water bath finished. After this step, 0.58 mL of 12 mol/L H2S04 solution was added, and the samples were again incubated in the water bath at 55 °C for 1.5 h for methyl esterification of the free fatty acids, with shaking for 5 s per 20 min. The supernatants were removed from the water bath and cooled to below room temperature under tap water, after which 3 mL of n-hexane was added to a centrifuge tube, and the material was centrifuged at 3000 rpm for 5 min. The supernatants were removed and filtered into a sample bottle using an organic phase filter membrane, and 2 mL of the sample was concentrated to below 1.5 mL at 45 °C. The processed samples were placed at −20 °C and analyzed for fatty acids by a gas chromatograph. We used an Agilent 6890 N gas chromatograph with an SP-2560 capillary column (100 m × 0.25 mm × 0.2μm, Sigma-Aldrich), FID hydrogen flame ion detector, carrier gas (N2) flow rate of 1.5 mL/min, and an air (combustion gas) flow rate of 400 mL/min. Each sample was injected in a split stream, with a split ratio of 1:100; the inlet temperature and the FID detector temperature were both 260 °C.

2.4. Extraction and LC-MS Analysis of Urine Metabolites

A pipette was used to draw 200 μL of defrosted urine into a 1.5 mL centrifuge tube, and 800 μL of precooled methanol/acetonitrile/water solution (4:4:2, v/v) was added. The mixture was swirled and then left to stand at −20 °C for 60 min; after centrifugation at 14,000 rpm 4 °C for 20 min, the supernatant was removed for vacuum drying. Mass spectrometric analysis was performed by adding 100 μL acetonitrile solution (acetonitrile: water = 1:1, v/v), redissolving, swirling, and centrifuging at 14,000 rpm for 15 min at 4 °C, after which the supernatant was fractionated by liquid chromatograph–mass spectrometer (LC-MS) analysis. A more detailed approach to the LC-MS procedure has been described in previous reports [27].

2.5. Statistical Analysis

SPSS 26 was used to analyze the meat fatty acids and production performance by using one-way ANOVA, and Duncan method was used for multiple comparisons. The data were presented as mean ± SD, and p < 0.05 was considered as statistically significant. GraphPad Prism 8.0.1 was used for graphics.
The raw data collected using MassLynx V4.2 were subjected to data processing operations, such as peak extraction and peak alignment by Progenesis QI software. The identification of the raw data was based on the online METLIN database of Progenesis QI software, with theoretical fragment identification and mass deviation within 100 ppm. After the original peak area information was normalized to the total peak area, a follow-up analysis was carried out. Principal component analysis and Spearman correlation analysis were used to judge the reproducibility of within-group samples and quality control samples. KEGG, HMDB, and lipidmaps databases were searched for the classification and pathway information on the identified compounds [28,29]. According to the grouping information, the difference multiples were calculated and compared, and the difference significance p value of each compound was calculated by a t-test. The R language package ropls was used to model OPLS-DA, and 200 permutation tests were conducted to verify the reliability of the model [30]. The differential multiples, p values, and VIP values of OPLS-DA model were used to screen the differential metabolites. The screening criteria were FC > 1, p < 0.05, and VIP > 1. Spearman correlations were used to analyze the relationships between muscle fatty acids and differential metabolites.

3. Results

3.1. Effect of Inulin and Chinese Gallotannin on Lamb Performance

There was no significant difference in ADG, DMI, FCR, and LW among groups (p > 0.05; Figure 1).

3.2. Effect of Inulin and Chinese Gallotannin on Meat Saturated Fatty Acids

Palmitic acid (C16:0) was the most abundant SFA and was found to be significantly lower in the treatment II group than in the other three groups (p < 0.05; Table 2; Figure 2 A). Myristic acid (C14:0) was also notably lower in treatment group II compared to the control group (p < 0.05; Table 2; Figure 2A). Stearic acid (C18:0) was also present at high levels, but these showed no obvious differences between the different groups (p > 0.05; Table 2; Figure 2A).

3.3. Effect of Inulin and Chinese Gallotannin on Meat Unsaturated Fatty Acid

The content of palmitoleic acid (C16:1) was greater in the treatment II group compared with the control group (p < 0.05; Table 3; Figure 2B), while elaidic acid (C18:1n9t) was more abundant in the treatment II group than in the other three groups (p < 0.05; Table 3; Figure 2B). Meanwhile, linoleic acid (C18:2n6c) was the highest among the 10 polyunsaturated fatty acids (PUFAs) in this study, with higher levels in the treatment group II and control groups than in the treatment I and treatment III groups (p < 0.05; Table 3; Figure 2C).

3.4. Effect of Inulin and Chinese Gallotannin on Meat Total Fatty Acid

The total SFA content in the treatment III group was higher than that in the other groups (p < 0.05; Table 4; Figure 2D). No difference was found among the groups for UFA, MUFA, and PUFA.

3.5. Screening of Differential Metabolites

The results of the OPLS-DA analysis showed that there were differences in the metabolites of Hu sheep between the control group and the three treatment groups (Figure 3A–C). Overall, we identified 146 differentially regulated metabolites (DRMs) between the control and treatment I groups, 467 DRMs between the control and treatment II groups, and 1399 DRMs between the control and treatment III groups (Figure 3D). In addition, we determined the number of common and unique DRMs in the four groups (Figure 3E). The results of the DRM clustering heatmap also confirmed considerable variations in the levels of urinary metabolites between the control group and the individual treatment groups (Figure 3F–H).

3.6. Functional Enrichment Analysis of Differential Metabolites

KEGG enrichment analysis of the DRMs among different groups presented the top 20 most significantly enriched metabolic pathways. The results confirmed that compared with the control group, the treatment I group exhibited enrichment in nicotinate and nicotinamide metabolism (ko00760); ether lipid metabolism (ko00565); vitamin B6 metabolism (ko00750); valine, leucine, and isoleucine biosynthesis (ko00290); and metabolic pathways (ko01100) (Figure 4A). The fatty acid biosynthesis pathway (ko00061) and ABC transporters pathway (ko02010) were more significantly enriched in the treatment II group (Figure 4B), while the glycerophospholipid metabolism (ko00564) and choline metabolism in cancer (ko05231) pathway were greater in the urine of the treatment III group (Figure 4C). At the same time, we selected the above metabolic pathways and DRMS, showing significant enrichment in the pathways for Sankey plot (Figure 4D). It can be clearly seen that the metabolic pathways involved by each DRMs, and some DRMs were also enriched in more than one metabolic pathway, such as l-threonine, 4-Pyridoxic acid, and PE (14:0/22:1(13Z)). Furthermore, Figure 4E–G also conforms to the observed upregulation and downregulation of DRMS in the control group and treatment groups I, II, and III.

3.7. Correlation Analysis

A correlation heatmap was created using Spearman correlations to identify possible relationships between the meat fatty acids and urine metabolites (Figure 5). The consequences confirmed that most of the muscle fatty acids were associated with urinary metabolites. Creatinine was found to be positively correlated with monounsaturated fatty acid (MUFA), and C18:1n9t and was negatively correlated with SFA and C17:0. Nicotinuric acid was positively correlated with C18:2n6c and negatively correlated with various fatty acids, such as C16:0, while 4-Pyridoxic acid was positively correlated with MUFA and C18:1n9t and negatively correlated with other fatty acids. In addition, muscle fatty acids that were positively correlated with LysoPC (16:0), including C14:0, C16:0, C18:1n9t, C18:2n6c, and SFA, had negative correlations with MUFA and C17:0. PE (14:0/24:0) was negatively associated with C18:2n6c and C17:0, but was positively associated with all other muscle fatty acids.

4. Discussion

4.1. Analysis of Meat Fatty Acid

Meat fatty acids are related to both meat tenderness and the formation of flavor compounds [31]. Of these, n-3 PUFA and n-6 PUFA are known as functional fatty acids for their anticancer, lipid-lowering, and cardiovascular disease-preventing properties [32,33]. In the current study, compared with the control group, the treatment II group showed lower SFA and increased UFA contents. Previous research has found that while the presence of excessive SFAs in foods does not solely lead to elevated total cholesterol (TCH) in the serum and low-density lipoprotein (LDL) levels, but it may also lead to cardiovascular disease [34]. Moreover, there is a positive correlation between C14:0 and C16:0 in SFA and serum TCH levels. Increases in these levels may lead to an elevation of LDL levels in the blood, which is a risk factor for cardiovascular disease [35]. It is known that UFA (consisting of PUFA and MUFA) is essential in the prevention of cardiovascular disorders [36,37]. As a UFA, C18:2n6c does not only improve meat quality, but can also lower blood triglyceride and cholesterol concentrations, with anticancer, and antidiabetic properties together with lowering the risk of cardiovascular disease [38]. The reduced contents of C14:0 and C16:0 and the increased content of C18:2n6c in the treatment II group indicate that the combination of inulin and Chinese gallotannin may be beneficial for the improvement of mutton quality.

4.2. Effect of Inulin Addition to Diet on Urine Metabolism in Hu Sheep

As an important prebiotic, inulin has beneficial impacts in both humans and animals [39,40,41]. In the present study, the addition of 0.1% inulin to the diet significantly changed the contents of nicotinuric acid, 4-pyridoxic acid, N1-Methyl-2-pyridone-5-carboxamide, and l-threonine in the urine of Hu sheep. It was reported that nicotinic acid could be derived from tryptophan and mainly involved in redox reactions as a core enzyme component as well as providing energy [42]. Furthermore, nicotinic acid is also an acyl glycine, acting as a coenzyme in several biological processes in the body, including glycolysis, gluconeogenesis, the citric acid cycle, and oxidation, as well as the formation of long-chain fatty acids [43]. Besides, the presence of acyl glycine in the urine could reflect the accumulation of acyl-CoA ester in the mitochondria [44]. Meanwhile, long-chain acyl-CoA ester, a major indicator of muscle lipid metabolism, may be negatively correlated with the effects of insulin [45,46]. Thus, changes in lipid metabolism may also affect blood glucose content. Moreover, l-threonine is mainly involved in the biosynthesis of amino acids and the metabolism of glycine, serine, and threonine in animals and plays a role in the regulation of energy homeostasis, nutrient metabolism, intestinal health, immunity, and ailment [47]. Thus, the addition of inulin may adjust the sugar metabolism and lipid metabolism of sheep by interfering with the metabolism of nicotinic acid and l-threonine, which are metabolites concerned with the metabolism of nicotinate and amino acids.

4.3. Effect of Inulin and Chinese Gallotannin Addition to Diet on Urine Metabolism in Hu Sheep

To clarify the potential mechanism responsible for the effects of the combination of inulin and Chinese gallotannin, the fatty acid biosynthesis pathway and ABC transporters pathway were investigated. We found that after the combined addition of inulin and Chinese gallotannin to the diet, the proportions of creatinine and 4-pyridoxic acid in the urine of Hu sheep increased, while the levels of palmitic acid, oleic acid, and other metabolites were downregulated. Research has found that creatinine is present in constant levels in the body and mostly filtered by way of the glomerulus without being absorbed by the renal tubules, so that changes in the creatinine levels primarily mirror the glomerular filtration function (renal excretory capacity) [48,49]. Thus, the increase in the urinary creatinine content in treatment group II suggests that the addition of inulin and Chinese gallotannin may have beneficial effects on the excretory capacity of the kidneys. Furthermore, 4-pyridoxic acid is a significant metabolite of vitamin B6 and can also be used as an indicator of amino acid metabolism in animals when amino acids are excreted via the kidneys and urine [50,51]. It has been reported that elevated levels of palmitic and oleic acid in animals can lead to pancreatic β-cell dysfunction and cardiomyocyte apoptosis, resulting in abnormal lipid metabolism [52,53]. Furthermore, the palmitic and oleic acid levels are related to changes in body weight [54]. However, in the current study, the contents of both palmitic and oleic acid were substantially decreased in the treatment II group compared with the control group, suggesting that the combination of inulin and Chinese gallotannin may regulate dysfunctional lipid metabolism in Hu sheep through modulating the metabolic and synthetic pathways of fatty acids, such as palmitic and oleic acids, ultimately enhancing the mutton quality.

4.4. Effect of Inulin, Chinese Gallotannin, and PEG Addition to Diet on Urine Metabolism in Hu Sheep

These three substances (inulin, Chinese gallotannin, and PEG) may be not suitable for simultaneous use as feed additives. We found that Lysophosphatidylcholine (LysoPC(20:5(5Z,8Z,11Z,14Z,17Z)), LysoPC(14:1(9Z)), LysoPC (16:0), and other LPCs in the urine of Hu sheep and phosphatidylethanolamine (PE (14:0/22:1(13Z)), PE (14:0/24:0)) were significantly raised in treatment III group (Figure 4G). These DRMs are significantly associated with glycerophospholipid and choline metabolism in the cancer associated with the sphingolipid signaling pathway (Figure 4D). Previous studies have shown that PE is one of the components of biological membranes, where it functions as a molecular chaperone, assisting in the correct folding of several membrane-associated proteins [55]. Moreover, LPC is an essential component of oxidized low-density lipoprotein, which is known to increase the production of inflammatory cytokines and has a variety of biological functions in cardiovascular disease, as well as being used as a biomarker for several diseases [56,57]. LPC has been shown to promote the formation of atherosclerotic plaques, exacerbate inflammation, enhance anti-infective responses, modify blood glucose, and also influence tumor invasion and metastasis [58,59]. It is thus concluded that the combination of inulin, Chinese gallotannin, and PEG may stimulate inflammatory reactions and lipid metabolism disorders in Hu sheep, which may be not conducive to the health of the sheep.

4.5. Correlation Analysis

The correlation analysis between meat fatty acids and urine metabolism indicated that these were clearly related and may influence one another, which give us a way to better understand the mechanism of the effect of additives on animal production performance. For example, 4-pyridoxic acid correlated with muscle fatty acids, which is a metabolite of vitamin B6. Vitamin B6 contributes to fatty acid biosynthesis [60]. This suggests that part of the action mechanism of inulin and Chinese gallotannin is to affect the synthesis of vitamin B6, and then affect the synthesis of fatty acids in animals. This is consistent with the fact that one of the nutritional effects of inulin is to benefit the synthesis of B vitamins by stimulating bifidobacteria growth in the intestine [61]. However, its specific mechanism needs to be further studied.

4.6. The Clinical Significance of the Study

Maintaining the balanced lipid metabolism is essential for both humans and animals. Lipids, as structural elements of cell membranes, could influence metabolic homeostasis through a variety of mechanisms and are necessary for the maintenance of metabolic homeostasis. As a necessary category of lipids, sphingolipids play vital roles in organisms. Complex sphingolipids can be converted into biologically energetic metabolites, such as sphingosine, sphingomyelin, and ceramide, that play essential roles in promoting cell recognition; inhibiting proliferation; and stimulating apoptosis, signal transduction, and cytokinesis [62,63]. Besides, the disordered lipid metabolism is also one of the essential elements influencing metabolic diseases [64,65]. In this study, the sheep in treatment group III showed some inflammatory reactions resulting from dysregulated lipid metabolism, which could be harmful to the health of the animal. Thus, the prevention of lipid metabolism disorders is necessary for both humans and animals.
Fatty acids play central roles in growth and development through their roles in membrane lipids, as ligands for receptors and transcription factors that regulate gene expression, as precursors for eicosanoids, in cellular communication, and through direct interactions with proteins [66]. The addition of inulin and Chinese gallotannin in diet would change the content of fatty acids in sheep. A lower the content of SFA and a higher the content of UFA is good for sheep health, which is in line with the demand of producers and consumers.

5. Conclusions

The combination of inulin and Chinese gallotannin (basal diet + 0.1% inulin + 2% Chinese gallotannin) as diet additives was beneficial in reducing the content of SFA and increasing the content of UFA in mutton, while enhancing both energy and lipid metabolism in Hu sheep. However, the combined addition of inulin, Chinese gallotannin, and PEG (basal diet + 0.1% inulin + 2% Chinese gallotannin + 4% PEG) under the current experimental situation did not produce a beneficial effect on the reduction of SFA content in mutton and is likely to cause inflammatory reactions and lipid metabolism disorders in Hu sheep.

Author Contributions

Conceptualization, Z.H., L.C. and S.L.; funding acquisition, S.L. and F.Z.; project administration, J.H., J.W. and X.L.(Xiu Liu); performed experiments, Z.H., Q.L. and X.L. (Xue Liang); data analyzed, Z.H.; writing, Z.H., L.C. and F.Z. All authors have read and agreed to the published version of the manuscript.

Funding

This research was financially supported by the fund for Natural Science Foundation of Gansu Province, China (20JR10RA536), the Fuxi Young Talents Fund of Gansu Agricultural University (Gaufx-03Y04) and the Discipline Team Project of Gansu Agricultural University (GAU-XKTD-2022-21).

Institutional Review Board Statement

The animal study protocol was approved by the Ethics Committee of Gansu Agricultural University (protocol code GSAU-2-th-AST-2021-001).

Informed Consent Statement

Not applicable.

Data Availability Statement

None of the data were deposited in an official repository.

Conflicts of Interest

We certify that there is no conflict of interest with any financial organization regarding the material discussed in the manuscript.

References

  1. Peng, Q.H.; Cheng, L.; Kun, K.; Gang, T.; Mohammad, A.M.; Bai, X.; Wang, L.Z.; Zou, H.W.; Gicheha, M.G.; Wang, Z.S. Effects of yeast and yeast cell wall polysaccharides supplementation on beef cattle growth performance, rumen microbial populations and lipopolysaccharides production. J. Integr. Agric. 2020, 19, 810–819. [Google Scholar] [CrossRef]
  2. Van Loo, J.; Coussement, P.; De Leenheer, L.; Hoebregs, H.; Smits, G. On the presence of Inulin and Oligofructose as natural ingredients in the western diet. Crit. Rev. Food Sci. Nutr. 1995, 35, 525–552. [Google Scholar] [CrossRef]
  3. Shoaib, M.; Shehzad, A.; Omar, M.; Rakha, A.; Raza, H.; Sharif, H.R.; Shakeel, A.; Ansari, A.; Niazi, S. Inulin: Properties, health benefits and food applications. Carbohydr. Polym. 2016, 147, 444–454. [Google Scholar] [CrossRef]
  4. Verdonk, J.M.; Shim, S.B.; van Leeuwen, P.; Verstegen, M.W. Application of inulin-type fructans in animal feed and pet food. Br. J. Nutr. 2005, 93 (Suppl. S1), S125–S138. [Google Scholar] [CrossRef]
  5. Vandeputte, D.; Falony, G.; Vieira-Silva, S.; Wang, J.; Sailer, M.; Theis, S.; Verbeke, K.; Raes, J. Prebiotic inulin-type fructans induce specific changes in the human gut microbiota. Gut 2017, 66, 1968–1974. [Google Scholar] [CrossRef] [Green Version]
  6. Uerlings, J.; Arevalo Sureda, E.; Schroyen, M.; Kroeske, K.; Tanghe, S.; De Vos, M.; Bruggeman, G.; Wavreille, J.; Bindelle, J.; Purcaro, G.; et al. Impact of citrus pulp or inulin on intestinal microbiota and metabolites, barrier, and immune function of weaned piglets. Front. Nutr. 2021, 8, 650211. [Google Scholar] [CrossRef]
  7. Tian, K.; Liu, J.H.; Sun, Y.W.; Wu, Y.J.; Chen, J.C.; Zhang, R.M.; He, T.L.; Dong, G.Z. Effects of dietary supplementation of inulin on rumen fermentation and bacterial microbiota, inflammatory response and growth performance in finishing beef steers fed high or low-concentrate diet. Anim. Feed Sci. Technol. 2019, 258, 114299. [Google Scholar] [CrossRef]
  8. Cerezuela, R.; Cuesta, A.; Meseguer, J.; Esteban, M.A. Effects of dietary inulin and heat-inactivated Bacillus subtilis on gilthead seabream (Sparus aurata L.) innate immune parameters. Benef. Microbes. 2012, 3, 77–81. [Google Scholar] [CrossRef]
  9. Liu, Y.; Li, Y.; Zhang, W.; Sun, M.; Zhang, Z. Hypoglycemic effect of inulin combined with ganoderma lucidum polysaccharides in T2DM rats. J. Funct. Foods 2019, 55, 381–390. [Google Scholar] [CrossRef]
  10. Zhang, S.; Yang, J.; Henning, S.M.; Lee, R.; Hsu, M.; Grojean, E.; Pisegna, R.; Ly, A.; Heber, D.; Li, Z. Dietary pomegranate extract and inulin affect gut microbiome differentially in mice fed an obesogenic diet. Anaerobe 2017, 48, 184–193. [Google Scholar] [CrossRef]
  11. Mueller-Harvey, I. Analysis of hydrolysable tannins. Anim. Feed Sci. Technol. 2001, 91, 3–20. [Google Scholar] [CrossRef]
  12. Biagia, G.; Cipollini, I.; Paulicks, B.R.; Roth, F.X. Effect of tannins on growth performance and intestinal ecosystem in weaned piglets. Arch. Anim. Nutr. 2010, 64, 121–135. [Google Scholar] [CrossRef]
  13. Gülçin, İ.; Huyut, Z.; Elmastaş, M.; Aboul-Enein, H.Y. Radical scavenging and antioxidant activity of tannic acid. Arab. J. Chem. 2010, 3, 43–53. [Google Scholar] [CrossRef] [Green Version]
  14. Ren, Y.Y.; Zhang, X.R.; Li, T.N.; Zeng, Y.J.; Wang, J.; Huang, Q.W. Galla chinensis, a Traditional Chinese Medicine: Comprehensive review of botany, traditional uses, chemical composition, pharmacology and toxicology. J. Ethnopharmacol. 2021, 278, 114247. [Google Scholar] [CrossRef]
  15. Aboagye, I.A.; Beauchemin, K.A. Potential of molecular weight and structure of tannins to reduce methane emissions from ruminants: A review. Animals 2019, 9, 856. [Google Scholar] [CrossRef] [Green Version]
  16. Waghorn, G. Beneficial and detrimental effects of dietary condensed tannins for sustainable sheep and goat production—Progress and challenges. Anim. Feed Sci. Technol. 2008, 147, 116–139. [Google Scholar] [CrossRef]
  17. Villalba, J.J.; Provenza, F.D. Preference for polyethylene glycol by sheep fed a quebracho tannin diet. J. Anim. Sci. 2001, 79, 2066–2074. [Google Scholar] [CrossRef] [Green Version]
  18. Silanikove, N.; Perevolotsky, A.; Provenza, F.D. Use of tannin-binding chemicals to assay for tannins and their negative postingestive effects in ruminants. Anim. Feed Sci. Technol. 2001, 91, 69–81. [Google Scholar] [CrossRef]
  19. Vlaanderen, J.J.; Janssen, N.A.; Hoek, G.; Keski-Rahkonen, P.; Barupal, D.K.; Cassee, F.R.; Gosens, I.; Strak, M.; Steenhof, M.; Lan, Q.; et al. The impact of ambient air pollution on the human blood metabolome. Environ. Res. 2017, 156, 341–348. [Google Scholar] [CrossRef]
  20. Sawano, S.; Oza, K.; Murakami, T.; Nakamura, M.; Tatsumi, R.; Mizunoya, W. Effect of gender, rearing, and cooking on the metabolomic profile of porcine muscles. Metabolites 2020, 10, 10. [Google Scholar] [CrossRef]
  21. Zheng, J.; Zhang, L.; Johnson, M.; Mandal, R.; Wishart, D.S. Comprehensive targeted metabolomic assay for urine analysis. Anal. Chem. 2020, 92, 10627–10634. [Google Scholar] [CrossRef]
  22. Karu, N.; Deng, L.; Slae, M.; Guo, A.C.; Sajed, T.; Huynh, H.; Wine, E.; Wishart, D.S. A review on human fecal metabolomics: Methods, applications and the human fecal metabolome database. Anal. Chim. Acta 2018, 1030, 1–24. [Google Scholar] [CrossRef]
  23. Wang, B.; Ma, M.P.; Diao, Q.Y.; Tu, Y. Saponin-induced shifts in the rumen microbiome and metabolome of young cattle. Front. Microbiol. 2019, 10, 356. [Google Scholar] [CrossRef] [Green Version]
  24. Wood, J.D.; Richardson, R.I.; Nute, G.R.; Fisher, A.V.; Campo, M.M.; Kasapidou, E.; Sheard, P.R.; Enser, M. Effects of fatty acids on meat quality: A review. Meat Sci. 2004, 66, 21–32. [Google Scholar] [CrossRef]
  25. Kowalczyk, J.; Skiba, B.; Buczkowski, Z.; Kowalik, B. A device for quantitative urine collection from male sheep in balance trials. J. Anim. Feed Sci. 1996, 5, 297–301. [Google Scholar] [CrossRef] [Green Version]
  26. Liu, T.; Lei, Z.M.; Wu, J.P.; Brown, M.A. Fatty acid composition differences between adipose depot sites in dairy and beef steer breeds. J. Food Sci. Technol. 2015, 52, 1656–1662. [Google Scholar] [CrossRef] [Green Version]
  27. Garcia, A.; Barbas, C. Gas chromatography-mass spectrometry (GC-MS)-based metabolomics. Metab. Profiling 2011, 708, 191–204. [Google Scholar]
  28. Wishart, D.S.; Feunang, Y.D.; Marcu, A.; Guo, A.C.; Liang, K.; Vazquez-Fresno, R.; Sajed, T.; Johnson, D.; Li, C.; Karu, N.; et al. HMDB 4.0: The human metabolome database for 2018. Nucleic Acids Res. 2018, 46, D608–D617. [Google Scholar] [CrossRef]
  29. Fahy, E.; Sud, M.; Cotter, D.; Subramaniam, S. LIPID MAPS online tools for lipid research. Nucleic Acids Res. 2007, 35, W606–W612. [Google Scholar] [CrossRef] [Green Version]
  30. Thevenot, E.A.; Roux, A.; Xu, Y.; Ezan, E.; Junot, C. Analysis of the human adult urinary metabolome variations with age, body mass index, and gender by implementing a comprehensive workflow for univariate and OPLS statistical analyses. J. Proteome Res. 2015, 14, 3322–3335. [Google Scholar] [CrossRef]
  31. Arshad, M.S.; Sohaib, M.; Ahmad, R.S.; Nadeem, M.T.; Imran, A.; Arshad, M.U.; Kwon, J.H.; Amjad, Z. Ruminant meat flavor influenced by different factors with special reference to fatty acids. Lipids Health Dis. 2018, 17, 223. [Google Scholar] [CrossRef]
  32. Panda, C.; Varadharaj, S.; Voruganti, V.S. PUFA, genotypes and risk for cardiovascular disease. Prostaglandins Leukot. Essent. Fat. Acids 2022, 176, 102377. [Google Scholar] [CrossRef]
  33. Mukherjee, A.; Kenny, H.A.; Lengyel, E. Unsaturated Fatty Acids Maintain Cancer Cell Stemness. Cell Stem Cell 2017, 20, 291–292. [Google Scholar] [CrossRef] [Green Version]
  34. Froyen, E. The effects of fat consumption on low-density lipoprotein particle size in healthy individuals: A narrative review. Lipids Health Dis. 2021, 20, 86. [Google Scholar] [CrossRef]
  35. Flock, M.R.; Kris-Etherton, P.M. Diverse physiological effects of long-chain saturated fatty acids: Implications for cardiovascular disease. Curr. Opin. Clin. Nutr. Metab. Care 2013, 16, 133–140. [Google Scholar] [CrossRef]
  36. Sokoła-Wysoczańska, E.; Wysoczański, T.; Wagner, J.; Czyż, K.; Bodkowski, R.; Lochyński, S.; Patkowska-Sokoła, B. Polyunsaturated fatty acids and their potential therapeutic role in cardiovascular system disorders—A review. Nutrients 2018, 10, 1561. [Google Scholar] [CrossRef] [Green Version]
  37. Hosomi, R.; Fukunaga, K.; Arai, H.; Kanda, S.; Nishiyama, T.; Kanada, T.; Yoshida, M. Effect of phospholipid n-3 polyunsaturated fatty acids on rat lipid metabolism. Eur. J. Lipid Sci. Technol. 2010, 112, 537–544. [Google Scholar] [CrossRef]
  38. Baublits, R.T.; Pohlman, F.W.; Brown, A.H.; Johnson, Z.B.; Proctor, A.; Sawyer, J.; Dias-Morse, P.; Galloway, D.L. Injection of conjugated linoleic acid into beef strip loins. Meat Sci. 2007, 75, 84–93. [Google Scholar] [CrossRef]
  39. Hernández-Sánchez, D.; Gómez-Hernández, J.L.; Crosby-Galván, M.M.; Hernández-Anguiano, A.M.; Ramirez-Bribiesca, J.E.; Aranda-Ibañez, E.; Gonzalez-Muñoz, S.S.; Pinto-Ruiz, R. 1632 Inulin as prebiotic for Lactobacillus salivarius and Enterococcus faecium with probiotic potential in ruminants. J. Anim. Sci. 2016, 94, 794–795. [Google Scholar] [CrossRef]
  40. Tripodo, G.; Mandracchia, D. Inulin as a multifaceted (active) substance and its chemical functionalization: From plant extraction to applications in pharmacy, cosmetics and food. Eur. J. Pharm. Biopharm. 2019, 141, 21–36. [Google Scholar] [CrossRef]
  41. Zou, Y.F.; Li, C.Y.; Fu, Y.P.; Feng, X.; Peng, X.; Feng, B.; Li, L.X.; Jia, R.Y.; Huang, C.; Song, X.; et al. Restorative Effects of Inulin from Codonopsis pilosula on Intestinal Mucosal Immunity, Anti-Inflammatory Activity and Gut Microbiota of Immunosuppressed Mice. Front. Pharmacol. 2022, 13, 786141. [Google Scholar] [CrossRef]
  42. Huang, C.F.; Cheng, M.L.; Fan, C.M.; Hong, C.Y.; Shiao, M.S. Nicotinuric Acid: A potential marker of metabolic syndrome through a metabolomics-based approach. Diabetes Care 2013, 36, 1729–1731. [Google Scholar] [CrossRef] [Green Version]
  43. Zuo, J.J.; Lan, Y.; Hu, H.L.; Hou, X.Q.; Li, J.S.; Wang, T.; Zhang, H.; Zhang, N.N.; Guo, C.N.; Peng, F.; et al. Metabolomics-based multidimensional network biomarkers for diabetic retinopathy identification in patients with type 2 diabetes mellitus. BMJ Open Diabetes Res. Care 2021, 9, e001443. [Google Scholar] [CrossRef]
  44. Jones, K.M. The mechanism of nicotinuric acid synthesis. Biochem. J. 1959, 73, 714–719. [Google Scholar] [CrossRef] [Green Version]
  45. Rinaldo, P.; Schmidt-Sommerfeld, E.; Posca, A.P.; Heales, S.J.R.; Woolf, D.A.; Leonard, J.V. Effect of treatment with glycine and L-carnitine in medium-chain acyl-coenzyme A dehydrogenase deficiency. J. Pediatr. 1993, 122, 580–584. [Google Scholar] [CrossRef]
  46. Ellis, B.A.; Poynten, A.N.N.; Lowy, A.J.; Furler, S.M.; Cooney, G.J. Long-chain acyl-CoA esters as indicators of lipid metabolism and insulin sensitivity in rat and human muscle. J. Appl. Physiol. Endocrinol. Metab. 2000, 279, E554–E560. [Google Scholar] [CrossRef] [Green Version]
  47. Bortoluzzi, C.; Rochell, S.J.; Applegate, T.J. Threonine, arginine, and glutamine: Influences on intestinal physiology, immunology, and microbiology in broilers. Poult. Sci. 2018, 97, 937–945. [Google Scholar] [CrossRef]
  48. Feng, J.; Li, X.; Pei, F.; Chen, X.; Li, S.; Nie, Y. 1H NMR analysis for metabolites in serum and urine from rats administrated chronically with La(NO3)3. Anal. Biochem. 2002, 301, 1–7. [Google Scholar] [CrossRef]
  49. Runesson, B.; Qureshi, A.R.; Xu, H.; Gasparini, A.; Lindholm, B.; Barany, P.; Elinder, C.G.; Carrero, J.J. Causes of death across categories of estimated glomerular filtration rate: The Stockholm CREAtinine Measurements (SCREAM) project. PLoS ONE 2019, 14, e0209440. [Google Scholar] [CrossRef]
  50. Toney, M.D. Reaction specificity in pyridoxal phosphate enzymes. Arch. Biochem. Biophys. 2005, 433, 279–287. [Google Scholar] [CrossRef]
  51. Tanaka, T.; Tateno, Y.; Gojobori, T. Evolution of vitamin B6 (pyridoxine) metabolism by gain and loss of genes. Mol. Biol. Evol. 2005, 22, 243–250. [Google Scholar] [CrossRef]
  52. Piccinin, E.; Cariello, M.; De Santis, S.; Ducheix, S.; Sabbà, C.; Ntambi, J.M.; Moschetta, A. Role of oleic acid in the gut-liver axis: From diet to the regulation of its synthesis via stearoyl-CoA desaturase 1 (SCD1). Nutrients 2019, 11, 2283. [Google Scholar] [CrossRef] [Green Version]
  53. Tsai, Y.W.; Lu, C.H.; Chang, R.C.; Hsu, Y.P.; Ho, L.T.; Shih, K.C. Palmitoleic acid ameliorates palmitic acid-induced proinflammation in J774A.1 macrophages via TLR4-dependent and TNF-alpha-independent signallings. Prostaglandins Leukot. Essent. Fat. Acids 2021, 169, 102270. [Google Scholar] [CrossRef]
  54. Hierons, S.J.; Abbas, K.; Sobczak, A.I.S.; Cerone, M.; Smith, T.K.; Ajjan, R.A.; Stewart, A.J. Changes in plasma free fatty acids in obese patients before and after bariatric surgery highlight alterations in lipid metabolism. Sci. Rep. 2022, 12, 15337. [Google Scholar] [CrossRef]
  55. Bogdanov, M.; Umeda, M.; Dowhan, W. Phospholipid-assisted refolding of an integral membrane protein. Minimum structural features for phosphatidylethanolamine to act as a molecular chaperone. J. Biol. Chem. 1999, 274, 12339–12345. [Google Scholar] [CrossRef] [Green Version]
  56. Zhou, X.S.; Wang, R.P.; Zhang, T.; Liu, F.; Zhang, W.; Wang, G.L.; Gu, G.R.; Han, Q.Q.; Xu, D.M.; Yao, C.L.; et al. Identification of lysophosphatidylcholines and sphingolipids as potential biomarkers for acute aortic dissection via serum metabolomics. Eur. J. Vasc. Endovasc. Surg. 2018, 57, 434–441. [Google Scholar] [CrossRef] [Green Version]
  57. Chang, M.C.; Lee, J.J.; Chen, Y.J.; Lin, S.I.; Lin, L.D.; Liou, E.J.W.; Huang, W.L.; Chan, C.P.; Huang, C.C.; Jeng, J.H. Lysophosphatidylcholine induces cytotoxicity/apoptosis and IL-8 production of human endothelial cells: Related mechanisms. Oncotarget 2017, 8, 106177–106189. [Google Scholar] [CrossRef] [Green Version]
  58. Liu, P.; Zhu, W.; Chen, C.; Yan, B.; Zhu, L.; Chen, X.; Peng, C. The mechanisms of lysophosphatidylcholine in the development of diseases. Life Sci. 2020, 247, 117443. [Google Scholar] [CrossRef]
  59. Hung, N.D.; Sok, D.E.; Kim, M.R. Prevention of 1-palmitoyl lysophosphatidylcholine-induced inflammation by polyunsaturated acyl lysophosphatidylcholine. Inflamm. Res. 2012, 61, 473–483. [Google Scholar] [CrossRef]
  60. Parra, M.; Stahl, S.; Hellmann, H. Vitamin B(6) and Its Role in Cell Metabolism and Physiology. Cells 2018, 7, 84. [Google Scholar] [CrossRef] [Green Version]
  61. Niness, K.R. Inulin and Oligofructose: What Are They? J. Nutr. 1999, 129, 1402S–1406S. [Google Scholar] [CrossRef]
  62. Quinville, B.M.; Deschenes, N.M.; Ryckman, A.E.; Walia, J.S. A comprehensive review: Sphingolipid metabolism and implications of disruption in sphingolipid homeostasis. Int. J. Mol. Sci. 2021, 22, 5793. [Google Scholar] [CrossRef]
  63. Kalinichenko, L.S.; Gulbins, E.; Kornhuber, J.; Muller, C.P. Sphingolipid control of cognitive functions in health and disease. Prog. Lipid. Res. 2022, 86, 101162. [Google Scholar] [CrossRef]
  64. Reiner, A.P.; Gross, M.D.; Carlson, C.S.; Bielinski, S.J.; Lange, L.A.; Fornage, M.; Jenny, N.S.; Walston, J.; Tracy, R.P.; Williams, O.D.; et al. Common coding variants of the HNF1A gene are associated with multiple cardiovascular risk phenotypes in community-based samples of younger and older European-American adults: The Coronary Artery Risk Development in Young Adults Study and The Cardiovascular Health Study. Circ. Cardiovasc. Genet. 2009, 2, 244–254. [Google Scholar]
  65. Wang, Y.; Ai, Z.; Xing, X.; Fan, Y.; Zhang, Y.; Nan, B.; Li, X.; Wang, Y.; Liu, J. The ameliorative effect of probiotics on diet-induced lipid metabolism disorders: A review. Crit. Rev. Food Sci. Nutr. 2022, 1–17. [Google Scholar] [CrossRef]
  66. Innis, S.M. Fatty acids and early human development. Early Hum. Dev. 2007, 83, 761–766. [Google Scholar] [CrossRef]
Animals 13 00160 g001 550
Figure 1. Effect of inulin and Chinese gallotannin on growth performance in sheep. (A) Dry matter intake; (B) average daily gain; (C) feed conversion ratio; (D) live weight.
Figure 1. Effect of inulin and Chinese gallotannin on growth performance in sheep. (A) Dry matter intake; (B) average daily gain; (C) feed conversion ratio; (D) live weight.
Animals 13 00160 g001
Animals 13 00160 g002 550
Figure 2. Analysis of the composition and contents of various fatty acids in the muscle tissues of lambs from the control and treatment groups I, II and III. (A) Composition and contents of saturated fatty acids; (B) composition and contents of monounsaturated fatty acids; (C) composition and contents of polyunsaturated fatty acids; (D) composition and contents of total fatty acids. * Indicates a significant difference between different trial groups (p < 0.05).
Figure 2. Analysis of the composition and contents of various fatty acids in the muscle tissues of lambs from the control and treatment groups I, II and III. (A) Composition and contents of saturated fatty acids; (B) composition and contents of monounsaturated fatty acids; (C) composition and contents of polyunsaturated fatty acids; (D) composition and contents of total fatty acids. * Indicates a significant difference between different trial groups (p < 0.05).
Animals 13 00160 g002
Animals 13 00160 g003 550
Figure 3. Analysis of differential metabolites between the control group and treatment groups I, II, and III of Hu sheep urine. (A–C) Clustering plots of partial least squares discriminant analysis (PLS-DA); (D) differentially regulated metabolites between the control group and treatment groups I, II, and III; (E) Venn diagram of differential metabolites between the different groups; (F–H) cluster heatmap of the differential metabolites between the control group and the treatment groups I, II, and III. A, control group (basal diet); B, treatment group I (basal diet + 0.1% inulin); C, treatment group II (basal diet + 0.1% inulin + 2% Chinese gallotannin); D, treatment group III (basal diet + 0.1% inulin + 2% Chinese gallotannin + 4% PEG).
Figure 3. Analysis of differential metabolites between the control group and treatment groups I, II, and III of Hu sheep urine. (A–C) Clustering plots of partial least squares discriminant analysis (PLS-DA); (D) differentially regulated metabolites between the control group and treatment groups I, II, and III; (E) Venn diagram of differential metabolites between the different groups; (F–H) cluster heatmap of the differential metabolites between the control group and the treatment groups I, II, and III. A, control group (basal diet); B, treatment group I (basal diet + 0.1% inulin); C, treatment group II (basal diet + 0.1% inulin + 2% Chinese gallotannin); D, treatment group III (basal diet + 0.1% inulin + 2% Chinese gallotannin + 4% PEG).
Animals 13 00160 g003
Animals 13 00160 g004 550
Figure 4. Functional enrichment analysis of differential metabolites in the urine of the control and treatment groups I, II, and III in Hu sheep. (A) Bar graphs of KEGG functional enrichment in control and treatment I groups; (B) bar graphs of KEGG functional enrichment in the control and treatment II groups; (C) bar graphs of KEGG functional enrichment in the control and treatment III groups; (D) graphs of differential metabolites in relation to their enriched metabolic pathways; (E) urinary differential metabolites between the control and treatment I groups; (F) urinary differential metabolites between the control and treatment II groups; (G) urinary differential metabolites in the control group versus the treatment III group; control group, basal diet; treatment group I = basal diet + 0.1% inulin; treatment group II, basal diet + 0.1% inulin + 2% Chinese gallotannin; treatment group III, basal diet + 0.1% inulin + 2% Chinese gallotannin + 4% PEG.
Figure 4. Functional enrichment analysis of differential metabolites in the urine of the control and treatment groups I, II, and III in Hu sheep. (A) Bar graphs of KEGG functional enrichment in control and treatment I groups; (B) bar graphs of KEGG functional enrichment in the control and treatment II groups; (C) bar graphs of KEGG functional enrichment in the control and treatment III groups; (D) graphs of differential metabolites in relation to their enriched metabolic pathways; (E) urinary differential metabolites between the control and treatment I groups; (F) urinary differential metabolites between the control and treatment II groups; (G) urinary differential metabolites in the control group versus the treatment III group; control group, basal diet; treatment group I = basal diet + 0.1% inulin; treatment group II, basal diet + 0.1% inulin + 2% Chinese gallotannin; treatment group III, basal diet + 0.1% inulin + 2% Chinese gallotannin + 4% PEG.
Animals 13 00160 g004
Animals 13 00160 g005 550
Figure 5. Spearman correlations between fatty acids and urine differential metabolites of sheep.
Figure 5. Spearman correlations between fatty acids and urine differential metabolites of sheep.
Animals 13 00160 g005
Table
Table 1. Basic diet composition and nutrient levels (dry matter basis).
Table 1. Basic diet composition and nutrient levels (dry matter basis).
Raw MaterialProportionNutrient LevelsContent
Ensilage corn stalks (%)8DM (kg/d)1
Alfalfa hay (%)22ME (MJ/kg)12.01
Corn (%)34CP (%)18.17
Soybean meal (%)14Ca (%)0.31
Rice bran (%)3P (%)0.30
Flax cake (%)3NDF (%)23.22
Corn DDGS (%)12
NaCl (%)0.7
Premix 1 (%)0.5
Puffing urea (%)1.3
NaHCO3 (%)1.5
Total (%)100
1 Premix is supplied per kilogram of feed: Vitamin A, 400–1000 IU; Vitamin D3, 75–400 IU; Vitamin E, 0.6–10 mg; Iodine, 0.075–0.425 mg; Selenium, 0.015–0.05 mg; Cobalt, 0.05–0.20 mg; Manganese, 4.1–15 mg; Fe, 4.5–18.08 mg; Zinc, 7.5–12 mg; Copper, 0.35–1.4 mg; Ca, 0.3 -1.2 mg; P, 0.075–2.5 mg.
Table
Table 2. Effect of inulin and Chinese gallotannin on meat saturated fatty acids in sheep.
Table 2. Effect of inulin and Chinese gallotannin on meat saturated fatty acids in sheep.
ItemTreatmentSEMp-Value
A 1B 2C 3D 4
C4:0 (%)0.08 ± 0.020.05 ± 0.020.06 ± 0.030.06 ± 0.040.010.271
C6:0 (%)0.15 ± 0.030.15 ± 0.030.13 ± 0.040.15 ± 0.030.010.630
C10:0 (%)0.17 ± 0.090.12 ± 0.040.11 ± 0.020.14 ± 0.020.010.277
C12:0 (%)0.20 b ± 0.050.22 b ± 0.120.41 a ± 0.140.39 a ± 0.130.030.006
C13:0 (%)0.33 a ± 0.090.21 b ± 0.030.22 b ± 0.050.25 ab ± 0.090.020.036
C14:0 (%)2.62 a ± 0.882.19 bc ± 0.391.95 c ± 0.352.49 ab ± 0.190.110.001
C15:0 (%)0.17 b ± 0.120.11 b ± 0.070.16 b ± 0.050.35 a ± 0.110.030.001
C16:0 (%)22.53 a ± 1.9822.77 a ± 2.4020.79 b ±1.7323.41 a ± 1.200.410.002
C17:0 (%)0.37 ab ± 0.070.44 a ± 0.180.43 a ± 0.090.28 b ± 0.050.030.042
C18:0 (%)15.03 ± 2.1315.52 ± 2.0216.13 ± 1.7015.65 ± 1.550.360.788
C20:0 (%)0.74 a ± 0.250.62 ab ± 0.150.63 ab ± 0.260.46 b ± 0.170.050.019
C21:0 (%)0.25 ± 0.140.31 ± 0.090.26 ± 0.100.19 ± 0.120.030.418
C22:0 (%)0.16 ± 0.050.20 ± 0.070.13 ± 0.040.16 ± 0.050.010.272
C4:0, butyric acid; C6:0, hexanoic acid; C10:0, decanoic acid; C12:0, lauric acid; C13:0, tridecanoic acid; C14:0, myristic acid; C15:0, pentadecanoic acid; C16:0, palmitic acid; C17:0, heptadecanoic acid; C18:0, stearic acid; C20:0, arachidic acid; C21:0, heneicosanoic acid; C22:0, behenic acid; PEG, polyethylene glycol; 1 control group (basal diet); 2 treatment group I (basal diet + 0.1% inulin); 3 treatment group II (basal diet + 0.1% inulin + 2% Chinese gallotannin); 4 treatment group III (basal diet + 0.1% inulin + 2% Chinese gallotannin +4% PEG); a–c Values within a row with different superscripts differ significantly at p < 0.05.
Table
Table 3. Effect of inulin and Chinese gallotannin on meat unsaturated fatty acids in sheep.
Table 3. Effect of inulin and Chinese gallotannin on meat unsaturated fatty acids in sheep.
ItemTreatmentSEMp-Value
A 1B 2C 3D 4
MUFA
C14:1 (%)2.01 ± 0.461.87 ± 0.692.14 ± 0.831.55 ± 0.420.120.409
C15:1 (%)0.23 ± 0.120.11 ± 0.060.15 ± 0.060.29 ± 0.180.030.073
C16:1 (%)1.08 b ± 0.201.47 ab ± 0.901.72 a ± 0.371.01 b ± 0.250.120.045
C17:1 (%)0.57 ± 0.090.47 ± 0.090.47 ± 0.060.47 ± 0.100.020.151
C18:1n9c (%)38.83 ± 2.9039.86 ± 2.2637.96 ± 2.7639.75 ± 0.640.470.465
C18:1n9t (%)1.31 bc ± 0.210.61 c ± 0.312.73 a ± 0.331.94 b ± 0.590.220.001
C20:1n9 (%)0.26 ± 0.130.25 ± 0.080.26 ± 0.080.24 ± 0.130.020.987
C24:1n9 (%)0.26 ± 0.070.19 ± 0.060.23 ± 0.090.29 ± 0.120.020.341
PUFA
C18:2n6c (%)7.21 a ± 0.826.20 b ± 1.007.75 a ± 1.826.27 b ± 0.600.260.034
C18:2n6t (%)0.11 ± 0.040.12 ± 0.050.14 ± 0.070.09 ± 0.030.010.431
C18:3n3 (%)0.43 ± 0.200.45 ± 0.140.38 ± 0.150.65 ± 0.270.050.258
C18:3n6 (%)0.12 ± 0.030.13 ± 0.020.09 ± 0.020.10 ± 0.050.010.401
C20:2 (%)0.39 a ± 0.110.23 b ± 0.110.27 ab ± 0.070.30 ab ± 0.140.020.028
C20:3n3 (%)0.55 a ± 0.240.40 a ± 0.140.39 a ± 0.150.28 b ± 0.070.040.026
C20:4n6 (%)2.97 ± 1.002.65 ± 0.972.81 ± 0.802.47 ± 0.550.170.771
C22:2 (%)0.34 ± 0.110.33 ± 0.080.26 ± 0.090.24 ± 0.120.020.279
C20:5n3 (%)0.29 a ± 0.080.24 ab ± 0.060.21 ab ± 0.030.19 b ± 0.050.020.038
C22:6n3 (%)0.48 ± 0.130.39 ± 0.130.40 ± 0.090.34 ± 0.040.020.280
MUFA, monounsaturated fatty acid; C14:1, myristoleic acid; C15:1, cis-10-Pentadecenoic acid; C16:1, palmitoleic acid; C17:1, cis-10-Heptadecenoicacid; C18:1n9c, oleic acid; C18:1n9t, elaidic acid; C20:1n9, cis-11-Eicosenoic acid; C24:1n9, nervonic acid; PUFA, polyunsaturated fatty acid; C18:2n6c, linoleic acid; C18:2n6t, linolelaidic acid; C18:3n3, α-linolenic acid; C18:3n6, γ-linolenic acid; C20:2, cis-11,14-Eicosatrienoic acid; C20:3n3, cis-11,14,17-Eicosatrienoic acid; C20:4n6, arachidonic acid; C22:2, cis-13,16-Docosadienoic acid; C20:5n3, cis-5,8,11,14,17-Eicosapentaenoic acid; C22:6n3, cis-4,7,10,13,16,19-Docosahexaenoic acid; PEG, polyethylene glycol; 1 control group (basal diet); 2 treatment group I (basal diet + 0.1% inulin); 3 treatment group II (basal diet + 0.1% inulin + 2% Chinese gallotannin); 4 treatment group III (basal diet +0.1% inulin + 2% Chinese gallotannin + 4% PEG); a–c Values within a row with different superscripts differ significantly at p < 0.05.
Table
Table 4. Effect of inulin and Chinese gallotannin on total fatty acids in sheep meat.
Table 4. Effect of inulin and Chinese gallotannin on total fatty acids in sheep meat.
ItemTreatmentSEMp-Value
A 1B 2C 3D 4
SFA (%)42.92 b ± 0.9042.91 b ± 2.2741.27 b ± 0.4446.91 a ± 1.150.620.001
UFA (%)57.16 ± 1.6256.88 ± 3.4558.29 ± 2.2055.93 ± 2.070.490.431
MUFA (%)44.27 ± 2.1445.74 ± 2.1045.64 ± 2.9844.98 ± 1.040.430.268
PUFA (%)12.89 ± 2.1111.14 ± 2.2812.66 ± 2.7110.96 ± 1.670.460.327
n-3PUFA (%)1.76 ± 0.381.48 ± 0.261.32 ± 0.361.36 ± 0.590.090.239
n-6PUFA (%)11.10 ± 0.679.10 ± 1.9510.80 ± 2.558.92 ± 1.080.400.104
SFA, saturated fatty acids; UFA, unsaturated fatty acid; MUFA, monounsaturated fatty acid; PUFA, polyunsaturated fatty acid, PEG, polyethylene glycol; n-3PUFA, n-3polyunsaturated fatty acid (C18:3n3, C20:3n3, C20:5n3, C22:6n3); n-6PUFA, n-6polyunsaturated fatty acid (C18:2n6c, C18:2n6t, C18:3n6, C20:4n6); 1 control group (basal diet); 2 treatment group I (basal diet + 0.1% inulin); 3 treatment group II (basal diet + 0.1% inulin + 2% Chinese gallotannin); 4 treatment group III (basal diet + 0.1% inulin + 2% Chinese gallotannin + 4% PEG); a–b Values within a row with different superscripts differ significantly at p < 0.05.
Disclaimer/Publisher’s Note: The statements, opinions and data contained in all publications are solely those of the individual author(s) and contributor(s) and not of MDPI and/or the editor(s). MDPI and/or the editor(s) disclaim responsibility for any injury to people or property resulting from any ideas, methods, instructions or products referred to in the content.

Share and Cite

MDPI and ACS Style

He, Z.; Cheng, L.; Li, S.; Liu, Q.; Liang, X.; Hu, J.; Wang, J.; Liu, X.; Zhao, F. Inulin and Chinese Gallotannin Affect Meat Quality and Lipid Metabolism on Hu Sheep. Animals 2023, 13, 160. https://doi.org/10.3390/ani13010160

AMA Style

He Z, Cheng L, Li S, Liu Q, Liang X, Hu J, Wang J, Liu X, Zhao F. Inulin and Chinese Gallotannin Affect Meat Quality and Lipid Metabolism on Hu Sheep. Animals. 2023; 13(1):160. https://doi.org/10.3390/ani13010160

Chicago/Turabian Style

He, Zhaohua, Long Cheng, Shaobin Li, Qiaoling Liu, Xue Liang, Jiang Hu, Jiqing Wang, Xiu Liu, and Fangfang Zhao. 2023. "Inulin and Chinese Gallotannin Affect Meat Quality and Lipid Metabolism on Hu Sheep" Animals 13, no. 1: 160. https://doi.org/10.3390/ani13010160

Note that from the first issue of 2016, this journal uses article numbers instead of page numbers. See further details here.

Article Metrics

Back to TopTop