[Energy utilization in growing sheep. Body retention of nutrients and experimental determination of energy efficiency and of the net energy content of the diet]

agneau agnelli alimentation des animaux alimentazione zootecnica analisi statistica analyse statistique animal feeding body measurements carcass composition composition de la carcasse composizione della carcassa cordero diet dieta energy metabolism energy value gain de poids ganancia de peso incremento di peso lambs mensuration corporelle metabolismo energetico misurazioni corporee statistical analysis valore energetico weight gain