ORIGINAL ARTICLE Digestibility and nitrogen utilization in sheep fed enset (Ensete ventricosum) pseudostem or corm and graded levels of Desmodium intortum hay to wheat straw-based diets A. Nurfeta Department of Animal and Range Sciences, College of Agriculture, Hawassa University, Hawassa, Ethiopia Introduction Enset (Ensete ventricosum) is widely distributed in central, eastern and southern Africa (Baker and Simonds, 1953) and Asia (Clark, 1967) but cultivated as a food and feed crop only in Ethiopia. It consists of three main parts: leaves, pseudostem and corm. Over 70% of the enset plant is composed of pseudostem and corm (Fekadu and Ledin, 1997; Nurfeta et al., 2008a). Enset is found at an altitude ranging from 1200 to 3100 m a.s.l. (Westphal, 1975). It supports approximately 20% of the Ethiopian popu- lation (Tsegaye, 2002). Feed availability and quality are the main problem affecting livestock productivity in smallholder enset/ livestock production systems of southern Ethiopia. As more land is being shifted to crop cultivation, land available for livestock feed becomes limited. As a result, utilization of different parts of enset as a feed is increasing from year to year. The use of enset as animal feed could play enormous role because of on-farm availability and easy access by farmers. Alemayehu et al. (2000), from their survey in three peasant association of Awassa Woreda (district), indi- cated that the contribution of enset to livestock feed is much higher compared to grazing land, stable grazing and browses put together. In some agro- ecological areas such as the highlands of Sidama and Gedeo, enset is fed throughout the year (Karin and Alemu, 1995). The fermented products from pseudostem and corm are used as a food, which is rich in starch. Keywords sheep, Ensete ventricosum, enset parts, supplementation, nitrogen supply Correspondence A. Nurfeta, Department of Animal and Range Sciences, College of Agriculture, Hawassa University, PO Box 222, Hawassa, Ethiopia. Tel: +25 191 6825 345; Fax: +25 146 2205 421; E-mail: ajebu_nurfeta@yahoo.com Received: 14 December 2008; accepted: 25 June 2009 Summary The aim of this study was to investigate the effects of different levels of Desmodium intortum (Desmodium) hay supplementation in sheep fed fixed amounts of enset pseudostem or corm and a basal diet of wheat straw on intake, digestibility and nitrogen utilization. Eighteen male sheep with a mean (± SD) live weight of 20.5 ± 1.45 kg were assigned to six treatments in a completely randomized design and fed either 108 g dry matter (DM) enset pseudostem or 165 g DM enset corm each with three levels (100, 200 and 300 g) of hay supplementation. For the pseudostem diets, there was no significant difference in total DM intake. Total crude protein (CP) intake and N retention increased with increasing levels of hay in both pseudostem and corm diets. The apparent digestibility of DM, OM, CP, acid detergent fibre and neutral detergent fibre (NDF) and microbial nitrogen supply (MN) at 100 g was lower that other levels of supplementation. For the corm diets, total DM and OM intake and MN supply increased with increasing levels of hay. The digestibility decreased (p < 0.001) with increasing levels of supplementation. The results suggest that at least 300 g (395 g/kg dietary DM) of Desmodium hay is required in pseudostem diets, whereas 200 g (337 g/kg dietary DM) may be sufficient in corm diets for efficient nutrient utilization. DOI: 10.1111/j.1439-0396.2009.00960.x Journal of Animal Physiology and Animal Nutrition 94 (2010) 773–779 ª 2009 Blackwell Verlag GmbH 773