Effect of dietary crude protein and energy content on nitrogen utilisation, water intake and urinary output in growing pigs

Abstract

A digestibility and balance trial was carried out with four intact castrated male pigs (live weight 33-82 kg) to study the effects of dietary crude protein and energy content on nutrient digestibility, nitrogen metabolism, water intake and urinary output. In a 4 ´ 4 Latin square design, four barley-oats-soya bean meal based diets were arranged 2 ´ 2 factorially. The corresponding factors were dietary crude protein (CP) content: high (180 g/kg CP) or low protein diet (140 g/kg CP) supplemented with free lysine, methionine and threonineLowering dietary CP content (mean values of 189 to 152 g/kg dry matter, respectively) by supplementation of free amino acids decreased urinary nitrogen (N) excretion by 6.9 g/day (32%) (P