Estrategias nutricionales en la alimentacion de cerdos de engorde para mitigar la excrecion de nitrogeno y fosforo al medio ambiente

Resum

This thesis addresses the implementation of nutritional strategies to reduce the excretion of pollutants (nitrogen and phosphorus) in fattening pigs. Lowering dietary CP, even in a narrow range and using CP levels close to commercial diets and environmental recommended values, urinary and total nitrogen excretion was decreased in the slurry of growing-finishing pigs in vitro, and ammonia emission was reduced, with no detrimental effects on growth performance in the growing period, in vivo. The phytase supplementation to low phosphorus diets, improved the growth performance and digestibility of phosphorus, calcium, copper and manganese. Phosphorus and copper were the most likely minerals to be affected by the addition of phytase, increasing their retention, which represented a decrease in the excretion into the environment from pig manure. Keywords: ammonia, pigs, pollutants, phitase