effect of partial replacement of barley with beet pulp on growth performance, digestibility and some histopathological alterations of rumen in lambs fed by high concentrate diets

in order to investigate effects of partial replacement of starch with neutral detergent soluble fiber (ndsf) on weekly weight gain, feed intake, feed conversion ratio, digestibility and some histopathological changes of rumen, 16 lambs were used in completely randomized design. the experimental period was 70 days. dietary treatments were 1- control (high starch), 2- beet pulp, 18 percent, 3- beet pulp, 36 percent and 4- beet pulp, 54 percent (high soluble fiber). lowest final weight and average daily weight gain observed in treatment 4 (p<0.05). treatment 4 had the lowest dry matter intake in the second and third weeks and over the whole experimental period. treatment 2 and treatment 3 showed the lowest while treatment 4 had the highest feed conversion ratio (p<0.05). highest total tract dm digestibility was observed in treatment 1. ndf and adf digestibility were significantly increased with increasing level of beet pulp in the diet (p<0.05). result of the histological pathology of rumen revealed a decrease in occurrence of parakeratosis and hyperkeratosis with increasing level of soluble fiber in the diet (p<0.05). the result of this study suggest that partial replacement of starch with neutral detergent soluble fiber from beet pulp to 36% of ration dry matter can improve animal growth performance presumably due to a reduce rumen histological damage