EDIBLE FORAGE PRODUCTION, CHEMICAL-COMPOSITION, RUMEN DEGRADATION ANDGAS-PRODUCTION CHARACTERISTICS OF CALLIANDRA-CALOTHYRSUS (MESSIN) PROVENANCES IN THE HUMID TROPICS OF WEST-AFRICA

Two experiments evaluated variations in feed value among Calliandra ca lothyrsus provenances. In Experiment I, edible forage production of fo ur provenances were evaluated at Ibadan, southwestern Nigeria over a 2 -year period in three seasons: main-wet (April-August), minor-wet (Sep tember-November) and dry (December-March). Forage samples from the mai n-wet and dry seasons were incubated for 6, 12, 48, 72 and 96 h in rum en:fistulated steers to estimate in sacco dry matter (DM) and nitrogen (N) degradation characteristics. In vitro gas production was estimate d over 3, 6, 12, 24, 48, 72 and 96 h of incubation. In Experiment 2, D M degradation characteristics of 14 provenances of C. calothyrsus plan ted on an acid soil in Yaounde, Cameroon, were evaluated. Data were su bjected to cluster analysis for grouping, and the 14 provenances were placed into four distinct cluster groups. Based on the potential exten t of DM and, N degradation and gas production characteristics in Exper iment 1, the four prove nances of C. calothyrsus were classified into three forage quality groups: high (ILCA 16310), medium (ILCA 14891, IL CA 15166) and low (NFTA 896). In Experiment 2, using the extent of DM degradation as a forage quality index, C. calothyrsus provenances in c lusters 3 and 4 (namely: 51/92, 11/91, 13191, 45/92, 10/91, 15/91, 18/ 91, 134/91, 12/91, 62/92), were relatively higher in quality than thei r counterparts in clusters 1 and 2. The results suggested the existenc e of intra-species variation among the provenances, and confirmed earl ier observations that forage quality of C. calothyrsus could be improv ed through provenance evaluation.