EFFECT OF THE REDUCTION OF THE OCUPATION PERIOD IN A BEEF CATTLE PRODUCTION SYSTEM BASED ON Brachiaria decumbens CV. SEÑAL. GUALACA, PANAMA. 2001-2003.

Abstract

The work was conducted by three years (2001-2003) in the Gualaca Experimental Station with the objective of determining the effect of the reduction of the occupation period (PO) on the production and productivity of the Brachiaria decumbens cv Señal on the raining season. lt was evaluated two occupation period: one and seven days, being constant the resting period one and seven days, being constant the resting period (PD) of 21 days. Each PO consisted of 2.5 ha of B. decumbens divided in 22 blocks of 1,136 m² each one and four blocks of 6,250 m² each one for one and seven days, respectively, using electric fence. B. decumbens was fertilized with 80 kg of N, 30 kg of P₂O₅ and 20 kg K₂O/ha, fractioned in three applications: June, August and November. lt was used a factorial arrangement in a randomized design. Stocking rate fluctuated between 3 to 6 head/ha with live weigth of 194 kg and was adjusted according to availability of forrage. Every year, animals were changed begining in May and finishing in January (240 days). Brahman, Zebu, F₁ Charolais, F₁ Simmental and Brown Swiss animals were used. Average daily gain for animal was 0.736 kg, while with PO of seven days was superior (P<0.01) to one day, 0.758 and 0.715 kg/d, respectively. Average beef production between periods was superior (P<0.01) in one day (819 kg/ha) than in seven days of PO. Stocking rate was high in 0.44 AU/ha more in one day than in seven day of PO. Dry matter availability (DM) per hectare per cycle of grazing between years was not significant (P>0.01); however, DM for one day of PO was higher (P<0.01) than seven days of PO (1,618 vs 1,182 kg DM/ha/grazing period). Less production cost of one kilogram of beef and higher profitability was obtained with B. decumbens with one day of PO (US $ 0.902 and 19%, respectively). lt was concluded that short PO period contributes to increase DM production, its quality, and so, its high weight gain per animal and hectare in the raining season.