Abstract: This study was conducted to investigate the effects of soybean oligosaccharides (SBOS) as antibiotic alternatives on growth performance and its mechanism in weaned piglets.Twelve Huanjiang mini-piglets weaned at 21 d of age were randomly allocated into two groups with six replicates in the feeding trial.The piglets were fed with a antibiotic- or 0.5% SBOS-supplemented diet for 14 days.Feed intake per piglet was recorded daily,and the body weight was got at the beginning or end of this trail,as well as collecting the blood.The plasma were separated by centrifugation and used for measuring blood biochemical parameters and contents of free amino acids.Ten Huangjiang mini-pigs were randomly allocated into two groups as same as the feeding trial in the digestion trial.After 4 d pretrial and 3 d official test,the feces were collected to determine the digestibility of dry matter,crude protein and crude fat by indicator method.The results showed that the average daily feed intake,average daily gain and feed/gain in piglets fed SBOS-supplemented diets didn’t differ with the control group; dietary supplementing SBOS decreased (P<0.05) the plasma contents of urea nitrogen and ammonia,while increased (P<0.05) the plasma content of total protein,compared with the control group; the plasma contents of glycine,histidine,lysine,arginine,and metione in piglets fed SBOS-supplemented diets increased (P<0.05),as well as the apparent digestibility of crude protein and fat (P>0.05),in comparison with the control group.These findings suggested that SBOS as antibiotic alternatives cloud be used in the diet of weaned piglets.

Key words: soybean oligosaccharides, blood biochemical parameters, nutrient metabolism