Effects of Chinese Herbal Polysaccharides on the Immunity and Growth Performance of Young Broilers1

ABSTRACT Two trials were conducted to study the effects of two Chinese herbal polysaccharides [achyran-than (ACH), a low-molecular-weight polysaccharide, and astragalan (APS), a high-molecular-weight polysaccaride] on the immunity and growth performance of young broil-ers. Trial 1 was a 28-d growth assay, in which 7-d-old broilers (n = 240) were randomly allotted to one of three dietary treatments, with eight replicate pens per treat-ment and ten chickens per pen. Dietary treatments in-cluded a control corn-soy-fishmeal (Treatment 1), a diet with 200 mg/kg APS (Treatment 2), and a diet with 200 mg/kg ACH (Treatment 3). Blood samples were collected by cardiac puncture on Days 7, 14, 21, and 28 for determi-nation of serum parameters, and chickens were killed on Day 28 to measure immune organ indexes. Trial 2 was an in vitro trial to study the effects of different concentra-tions of polysaccharides on broiler splenocyte functions