The behavior of lactation curve of 31 crossbred Saanen dairy goats and the effect of two strategies of supplementation with concentrate: 30% of requirements in net energy from third week until the end of lactation (ESC.1); or 60% of requirements in daily net energy from the 3rd to the 13th week and 15% from 14th until the end of lactation (ESC.2), in a pasture or semi-confined systems, were studied. The following models were evaluated: Wood linear and non-linear, Morant linear and non-linear, D-set and Grossman. Non-linear Wood model was the best in describing the behavior of lactation curve. The responses to the strategy of supplementation with concentrate were different in function of production systems. The strategy of supplementation affected the behavior of lactation curve more intensely in the semi-confined system. The ESC.2 strategy of supplementation resulted in more days to reach the production pick, in semi-confined system, and larger production in the lactation pick in both systems.
goat; lactation curve; milk production; strategies of supplementation
