Assessment and impact of grass and forage quality © 2013 Proceedings of the 22 nd International Grassland Congress 663 Dry matter, protein and fibre digestibility by West African Dwarf Sheep fed varying levels of Vernonia amygdalina meal in cassava starch residue – based diets O B Omotoso, A N Fajemisin, J A Alokan and YA Shuiabu Department of Animal Production and Health, Federal University of Technology, P.M.B 704, Akure, Nigeria Contact email: tos2bod@yahoo.com Keywords: Vernonia Amygdalina meal, digestibility, sheep, cassava. Introduction It is imperative to find alternative source(s) of feed for li- vestock in lieu of the limited availability of conventional concentrates and the competition for this resource by man. One plant with great potential for the livestock is bitter leaf (Vernonia amygdalina). It is wide spread with about 200 species, is edible, drought tolerant, nutritious and has been found to have medicinal qualities (John 1994). V. amygda- lina has an astringent taste which affects its intake. Bitter leaf meal contains 20-34% crude protein (CP) and can be used as protein supplement (Aregheore et al. 1998). With the recent introduction of trees and shrubs into cropping and grazing systems to provide high protein fodder to sup- plement post harvest crop residues, it is conceivable that V. amygdalina could play a valuable role in ruminant feeding system. This study was conducted to assess the dry matter, pro- tein and fibre digestibility by WAD sheep fed diets contain- ing various levels of Vernonia amygdalina leaf meal. Materials and Methods The experiment was conducted at Federal University of Technology, Akure (FUTA) (Latitude 7 0 18 ” and Longitude 5 o 10”E), Ondo state, Nigeria. Cassava starch residue was collected from a starch processing industry, gathered in a jute bag to ferment for 3-4 days before sun-drying for about 5 days on a concrete slab. Bitter leaves were also air dried after collection. The cassava starch residue and the bitter leaves were packed in jute bags, stacked in a store on a raised wooden platform until required for feeding. The cas- sava starch residue and bitter leaves were then sun-dried for one additional day to ensure perfect drying before milling and being used to make compound-feed. Palm kernel cake, brewer’s dried grain, salt and commercially produced pre- mix were purchased from a commercial feed mill. Five diets were formulated such that 0% (A), 25% (B), 50% (C), 75% (D) and 100% (E) of brewer’s dried grain was re- placed with V. amygdalina (w/w) respectively (Table 1). Fifteen WAD sheep with an average live weight of 15.5 kg ± 2.5 kg, ranging in age from 10-12 months, were treated against endo- and ecto-parasites and randomly assigned to a treatment. The experiment lasted for 63 days during which diets and water were given ad libitum to animals at 8.00am in the morning. Daily feed intake and weekly liveweights were recorded. Samples of feed, faeces and urine were ana- lyzed for dietary nutrients (AOAC 1995) and all data tained were subjected to analysis of variance using SAS 2008 version 9.2 Results and Discussion Table 1 presents intake, digestibility coefficients and weight gain of the experimental animals. Inclusion of bitter leaf meal influenced nutrient intake (P<0.05).The low in- take of DM, crude protein (CP), crude fibre (CF), ADF, NDF, and ADL on Diet E might be traced to the astringent taste and perhaps anti-nutritional compounds present in the bitter leaf. Intake on diet C was highest indicating it is more palatable and acceptable than other diets. The apparent di- gestibility of the fibre fractions, CP and DM were influenced significantly (P<0.05) with inclusion of bitter leaf meal and the digestion coefficient values of DM and CP varied from 557.6 (Diet E) to 788.4 (Diet C) g/kg and between 766.6 (Diet E) and 951.0 (Diet C) g/kg respective- ly. The favourable digestibility of DM and CP might be due to laxative, medicinal potentials and protein quality of bit- ter leaf meal supplementation in the diets. However, the digestibility of CP recorded for animals fed Diet E is low compared with the values of other diets. The ADF digesti- bility coefficient values observed varied, Diet C had the highest of 799 g/kg and Diet A had lowest value of 539 g/kg. Likewise Diet C had the highest NDF and ADL di- gestibility co-efficient values of 819 and 852 g/kg respectively. No statistical differences (P>0.05) were ob- served in the growth rate of the animals fed the different diets. The general growth rate of the animals on all treat- ments might be due to the adequate protein in the feed, which was comparable with the protein requirement and dry matter (DM) intake required for small ruminant growth according to Devendra (1980). Also the higher level of weight gain in Diet B might be due to more effective utili- zation of the feed and some physiological factors. The efficiency of feed utilization is best in Diet D (9.28) and poorest in Diet B (6.38) which might be attributed to the combined effects of level of bitter leaf meal inclusion in the diets and DM intake by the experimental animals which is higher than the range (0.10 – 0.25) reported by El-Hag et al (1986). Conclusion Results of this study indicate that Vernonia amygdalina leaf brought to you by CORE View metadata, citation and similar papers at core.ac.uk provided by University of Kentucky