Intake and milk production of suckling Creole goats reared at pasture in humid tropics according to the post-grazing residue management

Creole suckling goats, reared on rotationally grazed tropical pasture were used to study the effect of post-grazing residue control on forage intake and milk production. The pastures were irrigated and fertilized with 500 kg ha−1 year−1 of commercial fertilizer (30% N, 12% P2O5, 18% K2O). A system in which residuals were mown (RM) was compared to the control (Residuals Remained, RR) at three parturition seasons (dry, intermediate and wet). For both pasture management systems, each plot of 4100m2 was equally divided into five paddocks. Animals grazed the forage within each paddock for 7 days. Thereafter, pastures were grazed after every 28-day regrowth period for a full year. Each group at each season was composed of 20 goats weighing 36.0±2.5 kg LW (half of them were pregnant and half were lactating). Milk production (oxytocin method), live weight (LW), body condition score (BCS) and intake (fecal index method) were determined using six multiparous twin-bearing goats from each group for each season (35.2±5.0 kg LW) during 1 year. Herbage biomass (3.12 t DM/ha versus 4.98 t DM/ha, P < 0.001) was lower in RM than RR treatments while it was the opposite for the crude protein content of vegetation (123 g/kg DM versus 110 g/kg DM, P < 0.05). The organic matter digestibility, DM intake and organic matter intake averaged 0.695, 88 and 69 g/W−0.75, respectively. The daily milk production over the 12 weeks of lactation averaged 1.06 kg/day in both groups. The fat and protein contents reached on average 56 and 37 g/kg, respectively. Goats lost about 3.5 kg LW during lactation but did not lose BCS. No significant differences in intake, milk and body traits were observed among the two management systems (i.e. RM and RR). Seasonal effects (P < 0.01) were found and are discussed. Highest values were obtained during the intermediate season20% more forage (P < 0.05) and 17% more milk (P < 0.01). The forage biomass and feeding value were not limiting factors and generated adequate levels of intake and production whatever the pasture management system. Removing post-grazing residues in intensive grazing systems with suckling goats reared in tropical conditions, would not change the intake level or milk production of the does compared to the control system. It is recommended to develop new grazing systems, which would allow the use of post-grazing residues. © 2005 Elsevier B.V. All rights reserved