GROWTH-RATE, FEED-INTAKE AND FEED-UTILIZATION OF SMALL EAST-AFRICAN GOATS SUPPLEMENTED WITH LEUCAENA-LEUCOCEPHALA

Growth and digestibility studies with grazing indigenous Tanzanian goats used different levels of Leucaena leucocephala. Four treatments were hay only (H), hay and 100 g leucaena (HL1), hay and 200 g leucaena (HL2) and hay plus leucaena ad libitum (HL3) in the growth study; and hay only (H), hay and 100 g leucaena (HL1), hay and 200 g leucaena (HL2) and leucaena only (L) in the digestibility study. Supplemented goats had higher growth rates (P<0.001). Daily gains were 20, 23, 29 and 30 g for animals on treatments H, HL1, HL2 and HL3, respectively. Leucaena leucocephala supplementation increased total dry matter intake from 42.3 g/kg W0.75 in the control group (H) to 77.9 g/kg W0.75 in HL3 (P<0.001). Crude protein digestibility increased with higher levels of leucaena in the diet (P<0.001). Apparent digestibility of crude fibre was depressed with increased leucaena supplementation. Digestibility coefficients for treatments H, HL1, HL2 and L were 23.1, 55.2, 55.1 and 62.3 in trial 1 and 35.2, 49.3, 58.9 and 62.0 in trial 2 for crude protein; and 61.4, 60.9, 55.9 and 54.7 in trial 1 and 69.5, 59.1, 62.9 and 40.3 in trial 2 for crude fibre, respectively. Water intake and daily nitrogen retention increased with leucaena levels. Supplemented goats in HL1, HL2 and L retained 1.8, 3.5 and 9.6 g/day nitrogen compared to goats in H which were in negative nitrogen balance. © 1990.