Abstract :
Two diets were tested on Baladi lactating goats during mid-lactation in order to determine
their adaptive capacities facing feed restrictions: a low nutritive value pasture (LP) and a
high nutritive value pasture (HP). During early lactation on natural pastures, goats’ body
condition (BCS) degraded, as initially fat goats lost more weight (BW) and were subject to
a greater body reserves mobilization (BCS and NEFA) than lean ones. An intense compensation
for all goats followed their transfer to the HP whereas the mobilization continued
in LP, but only for fat goats. The lean goats managed to maintain their body condition by
increasing their feed intake. When moved to mixed agricultural pastures at late lactation,
all goats showed a full reconstitution of body reserves, particularly intense for those coming
from LP, showing their strong capacities to recover their body reserves at this period. In
parallel, milk production decreased for all goats on natural pastures, as the milk fat and milk
proteins content. After transfer to HP, the high lactation rebound (+36%) showed the good
reactivity of the Baladi goat in response to a feed improvement. Another rebound appeared
in groups coming from LP after being transferred to a better feeding condition. However,
during the reproduction phase, the milk yields decrease showing the highest priority given
to the body reserves recovery.
