The effect of breed and dietary level of avocado fat on the N and energy balance in young pigs

The effect of breed and dietary avocado level on the total apparent digestibility (RAD) and balance of nitrogen (N) energy, in young pigs, was studied. Four Pelon Mexican (PM) and four Yorkshire x Landrace (YxL) barrow male pigs (39.2 kg average inital liveweight) distributed in two groups according to a change over design in a 2x2 factorial arrangement (breed and diet) were used. The pigs received on a pair feeding basis (0.10 kg DM/kg W-0.75 per day), the experimental diets. The diets were formulated to contain 30 or 150 g crude fat by partial replacement of the maize/soyabean meal diet by avocado (Pet-sea americana Mill.) fresh pulp. The RAD of crude fat was 73.8 and 71.5% and that of N was 83.4 and 82.8% in PM and YxL pigs, respectively. There was no significant effect (P>0.10) of crude fat level on RAD of N and energy. N and energy balance significantly (P<0.05) favoured YxL as compared with PM pigs. In conclusion, the poor N retention of PM pigs could be related to body composition of this local, non improved genotype. The use of avocado for feeding pigs, PM included, should determine a high digestibility of the crude fat fraction and at the same time a considerable deterioration of N retention, probably due to an unbalanced composition of amino acids. The level of avocado pulp inclusion in the diet of the pig should be involved in these circumstances.