Effects of local energy sources on the in situ digestibility and ruminal kinetic of erythrina poeppigiana foliage in a silvopastoral system

Disponible para usuarios de ECOSUR con su clave de acceso

This study evaluated the effect of sorghum grain (Sg), green banana (Gb), polished rice (Pr), and sugarcane molasses (M o ) on the "in situ" digestibility ruminal kinetic of Poró ( Erythrina poeppigiana ) foliage under silvopastoral conditions in Turrialba, Costa Rica.Fou r ruminally cannulated Romosinuano steers with a mean live weight of 450 kg (SD 31 ) were used. The experiment was designed as a 4 x 4 Latin Square with one square and four periods . Steers grazed in twelve paddocks on pasture composed of African star - grass ( Cynodon niemfuensis ), ruzzy grass ( Brachiaria rusisiensis) , and natural grasses ( Axonopus compresus and Paspalum conjugatum ), under a rotational grazing system. Energy sources were supplemented at 0.60 Mcal ME /100 kg (BW) / day. The stee r were supplemented daily with fresh foliage (leaves, petioles, and stems) of Poró at 0.5 kg of DM/100 kg BW. Significant differences (P< 0.05) were found among the DM of energetic supplements for initial degradability , potential degradability and degradation rate . The effects of treatments on the degradability parameters of the DM of Erythrina and the grass blend as well as on N - NH 3 and pH content , were not significant (P < 0.05). In addition, t here were no significant differences (P< 0.05) among treatments for total concentration of volatile fatty acids ( VFA ́s ) (mmol) : (Pr = 87.0, G b = 95.0, Sg =96.0, Mo = 87.0); however, the proportion of a ce tic a cid, propionic acid and butyric acid presented significant differences (P > 0.05) due to the effect of the molasses. The fermentation pattern was typical of cattlegrazing diets under tropical conditions, with the molar proportion of acetic acid greater than 65%, between 13 and 16% for propionic acid and between 9 and 12% for butyric acid. eng