Adikari, A.A.S.Y.2021-03-182021-03-182012http://www.erepo.lib.uwu.ac.lk/bitstream/handle/123456789/6116/UWULD%20ANS%2008%200001-09042019090223.pdf?sequence=1&isAllowed=yUse of antibiotics as feed additives in animal feed have been highly regulated and even banned in some countries due to public health concerns associated with resistance development and residue effects. This experiment was conducted to assess the effect of natural yeast cell wall polysaccharide extract supplementation as an alternative for antibiotic growth promoters in broiler diets. Three hundred and sixty day old broiler chicks were divided into four treaiments with six replicate groups of 15 chicks and offered common basal diet supplemented either with natural yeast cell wall polysaccharide extract or commonly used antibiotic growth promoters (Bacitracin Methylene Disalicylate, Avilamycine) at recommended commercial levels and compared with negative control with no growth promoters for period of six weeks. Weekly group body weight, feed intake and daily mortality were recorded and calculated the group body weight gain, and feed to gain ratio. Subsequently five birds from each replicate were sacrificed and recorded carcass weight, liver, heart, gizzard, pancreas weights and length of small intestine. Dressing percentage was calculated. Data were analyzed using one way ANOVA. It was found that Yeast cell Wall Polysaccharides was at least as effective as the best antibiotic growth promoters available in the market if not better, However despite huge numerical deference between control and the said treatment deference was only statistically different only up to first 28 days only. However it is noticeable that the deference is important in commercial perspective and antibiotic growth promoters can be completely replaced using consumer friendly natural yeast cell wall polysaccharides in broiler diets in Sri LankaenAnimal Science Degree ProgrammeThesis