CaracteríSticas agronómicas, composición bromatológica, digestibilidad y consumo animal en cuatro especies de pastos de los generos brachiaria y panicum

Abstract

In order to select the most productive grass specie, four grasses were evaluated in terms of field performance, nutritive value and intake preference by sheep. The grasses were: Brachiaria brizantha cv Mulato, Brachiaria brizantha cv Toledo, Panicum maximum cv Tanzania and Panicum maximum cv Mombaza. Evaluation lasted 120 days, plant height every 30 days and at the end dry matter (DM), fiber fractions, crude protein (CP), in vitro digestibility and in vitro gas production were evaluated. A preference test was also carried out using male sheep (19 ± 3 kg). The main results were: Plant height was different (P<0.05), in each one of the sampling dates, being higher Toledo with 139.93 cm at 120 days; Mulato and Mombaza resulted in 8353 and 7903 Kg DM ha-1 (P<0.05). Animal preference was higher for Mombaza with an intake of 299.43 g DM día-1 (P<0.05). Higher values for NDF were registered in Mulato and Mombaza (66.32 and 68.45 %) (P<0.05). ADF was content was lower for Mulato (40.55 %); Tanzania presented the lowest value for organic matter (84.86 %) while the remaining species contained more than 87 % (P<0.05). CP was higher in Tanzania, Toledo and Mombaza (10.68, 9.55 and 9.33 % respectively) (P<0.05). Higher CP production was found in Mombaza (709.71 kg CP ha-1) (P<0.05). Toledo and Tanzania presented lower in vitro digestibility (64.19 and 56.99 %) (P<0.05). In vitro gas production at 72 hours was higher in Mulato and Mombaza (129.12 and 125.04 ml g-1 DM) (P<0.05). It was concluded that P. maximum cv. Mombaza is the grass with better agronomic performance, in vitro digestibility and higher preference by sheep.