An increased understanding of essential amino acid requirements has led to the ability to reduce dietary protein content while maintaining animal performance. A major assumption behind these low protein diets is that pigs are capable of producing sufficient amounts of non-essential AA (NEAA) to meet their demands for growth and so only need to be supplied with a source of EAA. However, to date there is insufficient evidence that this is the case. Thus, it is possible that non-essential amino acids/dietary nitrogen may become limiting in low protein diets. It is suggested that a minimum amount of NEAA (or total dietary nitrogen) is required in diets in order to maximize nitrogen retention. To maximize AA utilization, the EAA to total nitrogen ratio (EAA:TN) was determined in multiple species to be required to be approximately 0.50. While EAA requirements need to be met through inclusion of those specific AA in the diet, the source of nitrogen to meet dietary NEAA/nitrogen needs may not be as critical.
The nutrition research group at the Prairie Swine Centre has received funding from the Government of Saskatchewan through the Agriculture Development Fund to further investigate the importance of dietary nitrogen. The objectives of this series of studies will be to investigate the impact of dietary nitrogen content on essential amino acid requirements and amino acid utilization efficiency and to evaluate the effectiveness of alternative source of nitrogen to improve growth performance of pigs. The information gained from these studies will be used to provide recommendations to refine diet formulations to optimize nitrogen retention and lean gain in growing pigs.
We need to start thinking about more than essential amino acid requirements (full article)
