Dietary supplementation with Chinese herbal mixture extracts enhances growth performance, immunity, antioxidant capacity, and intestinal microbiota function in calves

Abstract

This study examined the effects of dietary supplementation with Chinese herbal mixture extracts (CHE) on growth performance, Immunity, antioxidant capacity, and gut microbiota composition in dairy calves. CHE is a compound extracts powder composed of Honeysuckle, Astragalus, Officinal magnolia bark, and Tangerine peel. Forty calves were randomly assigned to four groups: basal diet (CON), basal diet + 0.1% CHE (LCHE), basal diet + 0.2% CHE (MCHE), and basal diet + 0.4% CHE (HCHE). The experiment was conducted for 56 days with daily observations, bi-weekly weighing, blood sampling, and fecal collection toward the end. The addition of the CHE group significantly increased the average daily weight gain (ADG) and decreased the feed/gain ratio (F/G) compared to the CON group (p < 0.05). The apparent digestibility of crude fat, neutral detergent fiber, and acid detergent fiber was higher in HCHE and MCHE groups (p < 0.05). Serum GH and IGF-1 levels increased in MCHE and HCHE groups (p < 0.05). The blood biochemical analysis revealed that the levels of CA and GLU in the MCHE group were higher than those in the CON group, while remaining within the normal physiological range. Both the IgG and IFN-γ levels and the serum antioxidant levels were significantly increased in the CHE supplementation group compared with the control group (p < 0.05). High-throughput 16S rRNA sequencing revealed changes in gut microbiota, with increased unclassified Muribaculaceae and UCG-005 species in MCHE and HCHE groups (p < 0.05). In conclusion, CHE supplementation enhanced digestion, growth performance, immunity, and gut microbiota balance in calves without toxic side effects.Considering both the economic benefits and the effects of the additive, a clinical dosage of 0.2% CHE additive may be recommended.

Keywords: Chinese herbal mixture extracts; antioxidant capacity; calves; growth performance; immunity; intestinal microbiota.

Figure 1

Effects of CHE on feed intake and body weight of calves. (A) calves average daily feed intake level. (B) calves average daily weight level. (C) the feed-to-weight ratios level. CON group (fed basal diet), LCHE (basal diet + 0.1% CHE), MCHE (basal diet + 0.2% CHE), HCHE (basal diet + 0.4% CHE). Mean ± SEM are shown (n = 8).Significant differences (p < 0.05) are denoted by the distinct letters a and b.

Figure 2

Effects of CHE on Apparent nutrient digestibility of calves. EE, crude fat. NDF, neutral detergent fiber;ADF, acid detergent fiber; DM, dry matter; CP, crude protein. CON group (fed basal diet), LCHE (basal diet + 0.1% CHE), MCHE (basal diet + 0.2% CHE), HCHE (basal diet + 0.4% CHE). Mean ± SEM are shown (n = 5).Significant differences (p < 0.05) are denoted by the distinct letters a and b.

Figure 3

Effects of CHE on serum growth hormone of calves. (A) Serum GH level. (B) Serum IGF-1 level. CON group (fed basal diet), LCHE (basal diet + 0.1% CHE), MCHE (basal diet + 0.2% CHE), HCHE (basal diet + 0.4% CHE). Mean ± SEM are shown (n = 8). Significant differences (p < 0.05) are denoted by the distinct letters a and b.

Figure 4

Effects of CHE on serum immunoglobulin of calves. (A) Serum IgA level. (B) Serum IgG level. (C) Serum IL-8 level. (D) Serum IFN-γ level. CON group (fed basal diet), LCHE (basal diet + 0.1% CHE), MCHE (basal diet + 0.2% CHE), HCHE (basal diet + 0.4% CHE). Mean ± SEM are shown (n= 8).Significant differences (p < 0.05) are denoted by the distinct letters a and b.

Figure 5

Effects of CHE on serum antioxidant levels of calves. (A) Serum T-AOC level. (B) Serum SOD level. (C) Serum MDA level. (D) Serum GSH-PX level. CON group (fed basal diet), LCHE (basal diet + 0.1% CHE), MCHE (basal diet + 0.2% CHE), HCHE (basal diet + 0.4% CHE).Mean ± SEM are shown (n = 8).Significant differences (p < 0.05) are denoted by the distinct letters a and b.

Figure 6

Effects of CHE on the fecal-like flora of calves (A) Sample dilution curve plot. (B) Grouped box plots of the AlPha diversity index. (C) Two-dimensional ordination plot of samples analyzed by Beta Diversity PCoA. (D) Venn diagram.C (fed basal diet). L (basal diet + 0.1% CHE), M (basal diet + 0.2% CHE), H (basal diet + 0.4% CHE). Mean ± SEM are shown (n = 5).

Figure 7

Effects of CHE on the fecal-like flora of calves. (A) Distribution of taxonomic composition at the Phyla level. (B) Distribution of taxonomic composition at the genus level. (C) Distribution of taxonomic composition at the species level. C (fed basal diet). L (basal diet + 0.1% CHE), M (basal diet + 0.2% CHE), H (basal diet + 0.4% CHE). Mean ± SEM are shown (n = 5).

Figure 8

Correlation analysis chart. (A) Correlation analysis between phylum-level microbiota abundance and growth performance. (B) Correlation analysis between species-level microbiota abundance and growth performance. X-axis: microbial names. Y-axis: growth performance indicators. Red represents a positive correlation and blue represents a negative correlation. *p < 0.05, **p < 0.01.