Effects of supplementation of sole and combined browse leaves on <i>in vitro</i> digestibility of rice straw

Abstract

The utilization of browse leaves as quality livestock feeds during the late dry season can alleviate nutritional deficiencies and maintain livestock production. This study investigated the nutritional value in terms of dry matter (DM), crude protein (CP), ash, neutral detergent fibre (NDF), acid detergent fibre (ADF), in vitro dry matter digestibility (IVDMD) and in vitro organic matter digestibility (IVOMD) of both sole and combined browse leaves in Southern Ghana. Browse leaves used were Cajanus cajan (CC), Spondias mombin (SM) and Leuceana leucocephala (LL). Untreated Rice Straw (URS) was used as the basal diet which was harvested during the late dry season (September and October) from an irrigated rice field. The proportion of rice straw to browse leaves was 75 to 25 percent. Rumen liquor for the in vitro study was obtained from two forest type fistulated wethers of average weight 23 kg. The values for DM, CP, NDF, ADF and ash of the experimental diets ranges between 909.5 to 919.7 g/kg, 87.3 to 211.3 g/kg DM, 591.5 to 700.3 g/kg DM, 202.6 to 235.4 g/kg DM and 129.5 to 145.7 g/kg DM respectively. The combination of the three browse leaves (LLSMCC) had the lowest (p<0.05) ADF and NDF values whilst URS was the highest (p<0.05). All browses used improved the IVDMD of URS significantly from 388.7 g/kg DM to between 441 and 472.1 g/kg DM. The highest (p<0.05) IVDMD was obtained by the combination of Spondias mombin and Cajanus cajan (SMCC). Also, IVOMD of URS was improved from 346.4 g/kg DM to between 446.3 g/kg DM    and 483.4 g/kg DM. Results obtained from this study showed that browse leaves were high in CP and moderately low in crude fibre and ash hence, can be recommended as supplements for ruminants most especially in the dry season when feed is scarce.