EFFECT OF COCONUT OIL IN THE POST-WEANING STARTER DIET ON GROWTH AND CARCASS QUALITIES OF MALE LAMBS, WEANED EARLY AND INTENSIVELY FATTENEDIN WINTER

The influence of medium-chain fatty acids (5% coconut oil) introduced in a starter diet (ALc) for 21 d after weaning was investigated in 230 Lacaune male lambs. They were weaned early, intensively fattened duri ng winter and slaughtered at a constant live-weight (39 kg). Compariso ns have been made regarding the individual growth rates and carcass qu alities with an isocaloric and isonitrogenous reference diet (ALr) fro m lamb sub-samples. During the period of actual starter diet utilizati on, ALc induced a higher growth rate (+ 59%) independently of the wean ing weight (Wto). The feed conversion ratio was lower with ALc (P < 0. 01). The induced weight difference remained after the lambs were fed o n the same finishing diet. The growth pattern for the entire fattening period was more regular with ALc, particularly when lamb weight was m edium (1 2 kg) of light (Wto < 11 kg) at weaning. The volatile fatty a cid pattern in the rumen fluid over time (sampling with a rumen vacuum pump) and throughout the transition between starter and fattening die ts (Rusitec procedure) did not show a clear coconut oil effect. ALc in duced a slight increase in the external fat layer at slaughter 2 month s later, especially in heavy lambs. Firmness and colour of subcutaneou s fatty tissue were not different, but ALc tended to result in firmer and whiter carcasses in the case of the heavier lambs at weaning.