Effects of dietary energy level on antioxidant capability, immune function and rectal microbiota in late gestation donkeys

Abstract

The serum activity of catalase (CAT), total superoxide dismutase (T-SOD), glutathione peroxidase (GSH-Px), and total antioxidant capacity (T-AOC) in group M was significantly higher, whereas the concentrations of malondialdehyde (MDA), interleukin 1 (IL-1), IL-2, and IL-6 were lower than those recorded for groups H and L (<i>p</i> ≤ 0.05). The dietary energy level significantly affected rectal microbial community structure in the jennet donkeys 35 days and 7 days before the parturition (<i>p</i> ≤ 0.05). The abundances of <i>norank_f_norank_o_Coriobacteriales</i> genus was significantly higher (<i>p</i> ≤ 0.05) in group H, and the abundances of <i>norank_f_norank_o_Mollicutes_RF39</i> and the <i>Candidatus_Saccharimonas</i> were higher in group L (<i>p</i> ≤ 0.05). The abundance of Fibrobacter in group M was significantly increased (<i>p</i> ≤ 0.05). The abundance of <i>norank_f_norank_o_Coriobacteriales</i> was positively correlated with average daily gain (ADG) and tumor necrosis factor-α (TNF-α) concentrations (<i>p</i> ≤ 0.05). The abundance of <i>norank_f_norank_o_Mollicutes_RF39</i> was positively correlated with IL-2 and IL-6 concentrations. The abundance of <i>Candidatus_Saccharimonas</i> was positively correlated with CAT, T-SOD and GSH-Px activities (<i>p</i> ≤ 0.05). The abundance of Fibrobacter was positively correlated with CAT and T-SOD activities (<i>p</i> ≤ 0.05), but negatively correlated with IL-2 concentration (<i>p</i> ≤ 0.05). In conclusion, an appropriate dietary with an energy content of 10.49 MJ/kg for jennet donkeys during late gestation increased the prenatal antioxidant capacity, reduced inflammatory cytokines, and promoted fetal growth, and these changes were related to diet-induced changes in rectal microbiota compositions.