The Linear-Logistic Model: A Novel Paradigm for Estimating Dietary Amino Acid Requirements

Abstract

This study aimed to determine whether current methods for estimating AA requirements for animal health and welfare are sufficient. An exploratory data analysis (EDA) was conducted, which involved a review of assumptions underlying AA requirements research, a data mining approach to identify animal responses to dietary AA levels exceeding those for maximum protein retention, and a literature review to assess the physiological relevance of the linear-logistic model developed through the data mining approach. The results showed that AA dietary levels above those for maximum growth resulted in improvements in key physiological responses, and the linear-logistic model depicted the AA level at which growth and protein retention rates were maximized, along with key metabolic functions related to milk yield, litter size, immune response, intestinal permeability, and plasma AA concentrations. The results suggest that current methods based solely on growth and protein retention measurements are insufficient for optimizing key physiological responses associated with health, survival, and reproduction. The linear-logistic model could be used to estimate AA doses that optimize these responses and, potentially, survival rates.

Effects of increasing dietary arginine supply during the three first weeks after weaning on pig growth performance, plasma amino acid concentrations, and health status

“…Indeed, there is accumulating evidence that AA ingestion at levels greater than those required for maximum growth performance (or maximum nitrogen retention) benefits a variety of physiological processes in the organism such as protein turnover ( Young and Marchini, 1990 ) and transmethylation reactions ( Robinson et al, 2016 ). As suggested by Ramirez-Camba and Levesque (2013) , AA levels above those required for optimal growth are not necessarily detrimental or excessive to the animal but can actually improve its metabolic status, even more under stressful/challenging conditions.…”