LJ polysaccharides impacts the productivities and systemic health of ducks by modulating the intestinal microbiome and metabolome of ducks

The purpose of this experiment was to study the effects of laminaria japonica (LJ) polysaccharides on health parameters, intestinal microbiome and metabolome of ducks, and to explore the mechanism between intestinal microbiome, metabolites and health parameters, so as to develop new green additives for ducks. Forty-thousand 23-day-age Cherry Valley ducks with similar body weights were randomly assigned to two groups fed LJ polysaccharide or fed normally. After 14 days of continuous treatment, the average daily gain (ADG), average daily feed intake (ADFI), ratio of feed and gain (F/G) and nutrient apparent digestibility (NAD) of ducks in two groups were measured. The ducks were slaughtered on the 15th day (37 days of age) and samples were collected. Compared to Con group, ducks fed LJ polysaccharide had the greater ADG, DMD (dry matter digestibility), NDFD (neutral detergent fiber digestibility), CPD (crude protein digestibility), and lower ADFI. Additionally, the addition of LJ polysaccharides lowered the alpha-diversity of the cecum microbiota, whereas significantly increased the abundance of Bacteroides and Prevotellaceae, and upregulated the metabolic pathways related to growth performance, including vitamin B6, nicotinate and nicotinamide, and some essential amino acids, compared with the control group. Moreover, the abundance of the microbiota exerted an intimate correlation to the alterations of health parameters and metabolism pathways of ducks. In brief, feeding LJ polysaccharides ameliorated the health parameters of ducks. Thus, it is a recommendable dietary strategy to feed LJ polysaccharide to Cherry Valley ducks for superior product performance and feed efficiency.