Abstract :
Adaptive capacities of Baladi goats facing situations of food restrictions and re-feeding
during lactation have been studied. Three diets were tested: mountain natural rangelands
during early lactation, agricultural pastures during mid-lactation and indoor stall feeding
during late lactation. Body weight (BW), body condition (BCS) and plasma metabolites
(NEFA) as well as milk production (milk yield, milk fat and milk protein contents) were
measured in the different feeding situations. Effect of late lactation re-feeding on reproduction
was assessed through kids’ birth weight and weight gain from day 0 till day 60 of
age. Results showed that on rangelands, goats’ body condition degraded, with initially fat
goats loosing more weight and being subject to a greater reserves mobilization than lean
ones. These expressed an adaptive behaviour through increasing their daily feed intake and
by an intense body reserves replenishment following their transfer to the agricultural pastures
and indoor feeding. In late lactation, even goats kept on agricultural pastures showed
a similar reconstitution, showing the high priority of body reserves replenishment during
late lactation whatever the feeding level. The milk rebounds observed showed a good reactivity
from the Baladi goat in response to a feed improvement either on agricultural pasture
or indoor. At the end of lactation the milk yield decreased in all feeding situations proving
the priority given by the Baladi goats to the body reserves replenishment over the milk
production in order to ensure the next cycle. However, even if there was no difference in
kids’ birth weights, kids from stall-fed dams had higher weight gains between 0 and 60
days of age when compared to those from underfed ones.
