Dataset: Effects of Feeding High-moisture Corn on Milk Quality, Serum Antioxidant Indices and Intestinal Microflora of Chinese Holstein Cows

This study investigated the effects of replacing steam-flaked corn (SFC) with high-moisture corn (HMC) in the diet of Chinese Holstein dairy cows. Forty mid-lactation cows (parity 2-3) were randomly assigned to two groups: in the control group (YPFY group, n=20), cows were fed a diet containing SFC, while in the treatment group (GSFY group, n=20), cows were fed HMC with equal dry matter (n=20), with both diets being isoenergetic and isonitrogenous. The experiment included a 10-day adaptation followed by a 60-day feeding period. Milk components, serum antioxidant enzymes, and gut microbiota were assessed. Results showed that although milk yield was unaffected, the GSFY group exhibited a marked increase in milk fat percentage (P < 0.01), while lactose, protein, and solids-not-fat showed non-significant decreasing trends. Serum antioxidant capacity was significantly enhanced in the GSFY group, as indicated by elevated activities of superoxide dismutase, glutathione peroxidase, and catalase (P < 0.05). While gut microbial alpha diversity was unchanged, beta diversity revealed significant structural separation. HMC feeding increased the abundance of Bacteroidota but decreased Firmicutes_A and Actinobacteriota at the phylum level. At the genus level, Paraprevotella and Succinivibrio were enriched, whereas Prevotella and Faecousia were reduced (P < 0.05). Correlation analysis indicated a strong link between these microbial shifts and milk composition. In conclusion, HMC serves as a superior alternative to SFC, improving milk fat, enhancing systemic antioxidant status, and positively modulating the gut microbiota to optimize milk component synthesis in Chinese Holstein cows.