Nutritional outcome of n-soya replacement by n-urea in the sheep diet . Study of body-weight gain, n-digestibility, n-balance and 'ANTPOT.15N'-glycine kinetics - Lavezzo, O E N M; Lavezzo, W; Bicudo, M H; Boaretto, Antonio Enedi; Burini, R C (International Congress of Nutrition, 1993)