Resumen

VERGARA-LOPEZ, Juan; RODRIGUEZ-PETIT, Ángel; NAVARRO, Carlos  y  ATENCIO, Ángel. Effect of Leucaena Supplementation (Leucaena leucocephala Lam. De Wit) on Ruminal Degradability of Aleman-Grass (Echinochloa polystachya H.B.K. Hitch). Rev. Cient. (Maracaibo) [online]. 2006, vol.16, n.6, pp.642-647. ISSN 0798-2259.

To evaluate the effects of Leucaena supplementation on in situ ruminal dry matter (DM) degradability of Aleman-grass (AG), DM potential degradability (a+b), soluble fraction (a), maximum degradability (DM), degradation rate (c), ruminal pH and ammonia nitrogen, three ruminal cannulated Criollo Limonero steers were fed at 14-day adaptation period (F1) and samples were taken during the following 4-day period (F2). Diets were: T1, Aleman-grass (AG) + concentrate (CO); T2, PA + 2 kg Leucaena once a day and T3, PA + 2 kg Leucaena twice a day. During F2 nylon bags were sequentially incubated on 0; 6; 12; 24; 48; 72 and 96 h, and rumen contents pH were measured on 0; 3; 6; 9; 12 y 24 h post feeding. A Latin Square design with three replications was used and ruminal degradability data was analyzed by nonlinear regression model. No differences between treatments were found for a, b and c. a+b was higher (P < 0.05) on T3 (62.91%) than T1 (58.31%) or T2 (59.17%). Ruminal pH was higher (P < 0.05) in T3 (6.74) than T1 (6.66) and T2 (6.65). Ammonia nitrogen values were 405.00; 486.14 and 508.25 mg L^-1 for T1, T2 y T3, respectively. It was conclude that L. leucocephala fed twice a day increases DM degradability of Aleman-grass

Palabras clave : Ruminal degradability; supplementation; aleman-grass; leucaena.