Insights into the proteomic profile of newly harvested corn and metagenomic analysis of the broiler intestinal microbiota

BACKGROUND: The use of newly harvested corn in feed causes wet droppings in broilers and increased feed cost which was termed as “new season grain problem”. The present study was conducted to evaluate the proteomic profile of newly harvested corn and the subsequent influence on intestinal microbiol community for broiler chickens. METHODS: Newly harvested corn stored for either half a month (HM) or two months (TM) was used, and the pasting properties, total soluble sugars, and proteomic analysis technology was used to explore the influence of storage on natural aging corn properties. Additionally, seventy-two 7-day-old Ross 308 male broiler chicken were fed with different stored corn. Apparent metabolizable energy (AME), digesta viscosity, intestinal morphology and microbiota were examined to explore the influence of feed corn storage on broiler chickens. RESULTS: Pasting properties in the TM corn exhibited decreased viscoelastic properties. Proteomic studies found a total of 26 proteins that were differentially expressed between the two treatment groups. Proteins involved in starch and polysaccharides biosynthesis were upregulated in TM compared with HM. Chickens fed on TM diet had higher relative energy utilization compared to the HM birds. With increased corn storage, the relative digesta viscosity decreased significantly (P ≤ 0.05). The total number of goblet cells and lymphocytes was lower in chickens fed the TM diet. The microbiota data showed that the TM chickens had decreased abundance of diarrheal bacteria such as Hungatella hathewayi and Bacteroides fragilis, and increased butyrate-producing bacteria such as Alistipes compared to the HM chickens. CONCLUSIONS: Storage of newly harvested corn induced the synthetic reaction of large molecules and changed the solubility of starch and protein with increasing soluble sugars and decreasing pasting properties that may improve the fermentation of intestinal microbiota, improve the energy utilization and protect gut health without the risk of diarrhea.