In vitro digestibility and in situ rumen degradability of browse plants from natural pastures in Senegal. First results

Abstract

To evaluate the apparent digestibility of trees and shrubs browsed in Sahelian and Sudanian areas of Senegal, an in vitro method was used (Tilley and Terry’s method: dry matter (IVDM) and organic matter (IVOM) digestibility) as well as an in situ method (intra-ruminal degradability of dry matter and nitrogen). In 58 analysed samples, the average IVDM and IVOM were 51 and 42 %, ranging from 26 to 88 % and from 15 to 84 %, respectively. A total of 38 degradation profiles (in sacco) involving 24 species gave a mean degradability of 59 and 57 % for nitrogen and dry matter, respectively. Variation factors linked to species, age and plant parts were observed and a provisional classification of studied species proposed.