The use of sweet potato (Ipomoea batatas (L.) Lam) root as feed ingredient for broiler finisher rations in Papua New Guinea

• Cost of manufactured stock feeds in PNG has increased from 56 to 110% in the last 10 years.
• Sweet potato roots from PNG can be used up to 50% in broiler diets without having adverse effect on feed intake.
• The dietary fibre component of sweet potato has anti-microbial and chemo preventive attributes.
• Further investigation is necessary to study if sweet potato is to be used regularly in broiler diets.

The use of non conventional feedstuffs in poultry rations is now a common practice in developing countries where most of the ingredients used in the production of commercial poultry stockfeed are imported grains. The prices of these grains are dictated by world market prices and this translates into high retail prices for the end users. The purpose of this review is to highlight the potential of sweet potato root as a poultry feed ingredient especially for finishing off broilers in Papua New Guinea where this root crop is in abundance. This review discusses in general the metabolisable energy value of this crop when compared to maize and its impact on the intake of broilers when processed differently and fed at various inclusion rates. Trypsin inhibitors are the major anti-nutritive factor present in sweet potato roots; however these are eliminated with heat moisture treatments. The dietary fibre in sweet potato roots have been shown to have anti-microbial and prebiotic attributes which may be beneficial in promoting good gut health in chickens. The use of exogenous enzymes in sweet potato diets is briefly mentioned in this review. All in all, sweet potato roots can be included in diets for broiler chickens at 30% without adversely affecting intake of birds if processed correctly. However, to date limited information is available on how sweet potato can enhance digestive capacity of broiler in terms of gut morphology and digestive enzyme activities, as well as the shedding of the main zoonotic bacteria such as Campylobacter and Clostridium perfringens. The shedding of these bacteria in relation to food safety is important if sweet potato is to be used regularly in finishing off broilers in PNG.