Body composition of goat kids during sucking. Voluntary feed intake.

The body composition of thirty-eight Granadina goat kids was measured. Six animals were slaughtered at birth while the remainder were kept individually at an environmental temperature of 24 +/- 2 degrees and a relative humidity of 60 +/- 5%. They were given goat's milk or a milk-substitute at two planes of nutrition until 15 or 30 d of age and then slaughtered. The goat's milk and milk-substitute contained 260.4 and 222.0 g digestible protein/kg and 23.23 and 20.85 MJ metabolizable energy/kg respectively. Voluntary feed intake as metabolizable energy was a function of metabolic body-weight (kg W0.75), equivalent to 2.42 and 2.44 times the energy requirement for maintenance for goat's milk- and milk-substitute-fed animals respectively. There was a high degree of correlation between the empty-body concentration of dry matter, fat and energy and empty-body-weight (P less than 0.001) or animal age (P less than 0.001), and between body-weight and animal age (P less than 0.001). The relationships between empty-body composition and empty-body-weight were independent of type of milk or plane of nutrition. In contrast relationships between empty-body composition or empty-body-weight and animal age were affected by the type of milk and, over all, by the plane of nutrition. All these results show that in these animals any body-weight will have a similar composition, but it will be reached earlier or later depending on dietary regimen and always with the limitation of voluntary intake.