Effects of Purple Corn Anthocyanin on Blood Biochemical Indexes, Ruminal Fluid Fermentation, and Rumen Microbiota in Goats

The objective of this study was to observe the effects of anthocyanin from purple corn on blood biochemical indexes, ruminal fluid fermentation parameters, and the microbial population in goats. A total of 18 Qianbei Ma wether kids (body weight, 21.38 ± 1.61 kg; mean ± standard deviation) were randomly assigned to three groups using a completely randomized design. The group diets were: (1) control, basal diet, (2) treatment 1 (LA), basal diet with 0.5-g/d purple corn pigment (PCP), and (3) treatment 2 (HA), basal diet with 1-g/d PCP. The results showed that supplementation of PCP anthocyanin increased (P < 0.05) crude protein and gross energy digestibilities compared to the control. Compared to the control group, the inclusion of anthocyanin-rich PCP led to significantly increased (P < 0.05) plasma reduced glutathione and peroxidase concentrations. Goats receiving PCP had increased (P < 0.05) ruminal fluid acetic acid and a higher ratio of acetate to propionate, while the propionic acid, butyric acid, valeric acid, isobutyric acid, and isovaleric acid levels had decreased (P < 0.05). There was no significant difference (P > 0.05) in ruminal fluid alpha bacterial diversity among the three groups. At the phylum level, the feeding of PCP had significant effect (P < 0.05) on the abundances of Actinobacteriota, Proteobacteria, Elusimicrobiota, WPS-2, and Cyanobacteria. At the genus level, HA group had lower (P < 0.05) Prevotellaceae_NK3B31_group abundance compared to the other groups. In addition, significant differences (P < 0.05) were also observed for the ruminal fluid Eubacterium_nodatum_group, Amnipila, Ruminiclostridium, U29-B03, unclassified_c_Clostridia, Pyramidobacter, Anaeroplasma, UCG-004, Atopobium, norank_f_norank_o_Bradymonadales, Elusimicrobium, norank_f_norank_o_norank_c_norank_p_WPS-2, norank_f_Bacteroidales_UCG-001, and norank_f_norank_o_Gastranaerophilales among all groups. Taken together, the inclusion of anthocyanin-rich PCP increased the antioxidant potential, improved rumen volatile fatty acids, and induced a shift in the structure and relative abundance of ruminal microbiota in growing goats.