An experiment was carried out to evaluate the digestibility of diets and metabolism of pigs fed diets containing sodium bentonite subjected to different feeding programs. Twenty-four barrows were used, littermates, 42.2kg initial live weight, housed in metabolic cages. Experimental design was completely randomized with three sodium bentonite levels (0.0; 0.3 and 0.5%) and two feeding programs (restricted and ad libitum), with eight replications each. Addition of sodium bentonite didn't affect (P>0.05) the feed intake, the energy and N balance. The feed intake differ (P<0.01) between restricted and ad libitum feeding (1.17 vs. 2.19kg d-1). The feeding program alter (P<0.05) the N balance, but don't affected (P>0.05) the N retention in pigs. Ad libitum feeding alter (P<0.05) the energy balance, mainly the retained energy (3,825 vs. 3,013kcal d-1). Addition of 0.5% of sodium bentonite in diets reduced in 9% (P<0.01) the fecal phosphorus excretion. Sodium bentonite in diets doesn't alter the energy and N balance neither apparent digestibility of Ca, Mg, Zn, Cu and Mn. Sodium bentonite in diets reduce the fecal phosphorus excretion. There is no interaction between the feeding program and the addition of sodium bentonite in diets.
ad libitum feeding; clays; minerals; nutrients; restricted feeding