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

摘要

Experiments were designed with Martinik suckling ewes, reared on rotationally grazed tropical pasture, in order to test the effect of post-grazing residue control on forage intake and milk production. A system in which residuals were mown (RM) was compared to the control (Residuals Remained, RR) during three seasons (dry, intermediate and wet). Each group at each season was composed of 20 ewes (46.8+or-2.4 kg LW). Milk production (oxytocin method), live weight (LW), body condition score (BCS) and intake (fecal index method) were determined on six multiparous twin-bearing ewes in each group and at each season (47.5+or-6.0 kg LW). The herbage biomass and chemical composition were at a satisfactory level for tropical forages: biomass on offer reached 2.54 vs. 3.75 t.ha-1 DM, (P<0.001) for RM and RR, respectively; and the CP content was around 100 g.kg-1. The DMI and OMI, expressed as g.kg-0.75, were 103+or-18 and 81+or-14, respectively. On average, the daily milk production of the ewes reached 1.2+or-0.3 kg.d-1. The fat and protein contents of the milk were 66+or-17 and 52+or-13 g.kg-1, respectively. The ewes did not significantly loose LW or BCS during lactation. No significant differences in MP and intake traits were observed in terms of pasture management and seasonal effects. The forage characteristics were not limiting factors and generated an adequate level of intake and production whatever the pasture management system..