Chemical and Mineral Composition, Kinetics of Degradation and in vitro Gas Production of Native Cactus

Abstract

This study aimed to evaluate the chemical and minerals composition, fractions of carbohydrate and nitrogen compounds, kinetics of degradation and in vitro gas production of native cactus species of the brazilian Semiarid. The experiment was conducted in a completely randomized design, with five native cactus species and 4 replications per species were randomly selected. The native cactus species evaluated were: Cereus jamacaru DC., Melocactus bahiensis Br. Et Rose Werderm, Opuntia inamoene K. Schum, Pilosocereus gounellei (A. Weber ex K. Schum) Bly ex Rowl and Pilosocereus pachycladus Ritter, all in natura. The native cactus species showed differences for chemical and mineral compositions (P <0.05). The nitrogenous components, C. jamacaru cactaceae presented higher contents of fractions A (228.1 g/kg CP) and B3 (241.7 g/kg CP) and smaller fraction C (174.0 g/kg CP). For carbohydrate fraction C. jamacaru presented lower fractions A + B1 (412.2 g/kg TC) and C (38.2 g/kg TC) and high fraction B2 (549.7 g/kg TC) and low fraction C. The cactus C. jamacaru and M. bahiensis presented a high PD (856.6 and 837.9 g/kg DM, respectively). The parameters a and b and the effective degradability present diferences (P<0.05) in function of 2% and 5% passage rate. The in vitro true digestibility of dry matter was above 700 g/kg of DM for all species. Cactus have high levels of potentially digestible fractions of total carbohydrates, indicating their importance as food for ruminants in created in the semiarid, where Caatinga vegetation is a basal resource.