Effect of dietary molasses on the site and extent of digestion of nutrients in sheep fed broiler litter

Abstract

The aim of this experiment was to determine the site and extent of digestion of nutrients in sheep fed broiler litter alone (100% litter treatment), broiler litter plus 7.5% sugarcane molasses (92.5% litter treatment) and broiler litter plus 15% molasses (85% litter treatment). Voluntary intake was increased by molasses, apparently due to an increased rate of passage of digesta through the digestive tract. This resulted in a shift in the site of disappearance of organic matter (OM) from the rumen towards the lower digestive tract. For the 100 and 92.5% litter treatments, 0.37 and 0.46 of dietary OM disappeared in the rumen respectively, compared to 0.21 for the 85% litter treatment, while 0.16, 0.08 and 0.35 of dietary OM disappeared in the small intestine for the 100, 92.5 and 85% litter diets respectively. In the case of the 85% litter treatment, 0.26 of dietary nitrogen (N) disappeared in the rumen and 0.45 in the small intestine, compared to 0.55 and 0.62 in the rumen and 0.18 and 0.11 in the small intestine for the 100 and 92.5% litter diets respectively. There were no differences between treatments for total tract apparent digestibility of N (0.73) and OM (0.65-0.73), rumen degradability of N (71-87%) or concentration of ammonia-N in rumen fluid (53 mg/100 ml). It was concluded that the addition of molasses might be advantageous when the intake of litter is restricted or when voluntary intake of litter is unacceptably low.


(South African Journal of Animal Science, 2001, 31(1): 33-40)