Sampling Errors Associated with Protein Accretion and Amino Acid Requirements Predicted from Serial Live Weight and Real-Time Ultrasound Measurements

Purdue Universtiy 1998 Swine Research Report. Currently, swine nutritionists formulate diets based upon estimates of lean accretion or protein requirements in controlled university or private research facilities. However, these dietary recommendations may not be correct because of farm-to-farm differences, environmental conditions, health status, stocking density, air quality, social factors and other factors. Methods have been developed in which farm-specific protein accretion curves and daily lysine requirements can be estimated. The technique has been used in numerous farms with different genetics. In most cases, 32 to 40 barrows and gilts have been weighed and ultrasonically measured every three weeks from 50 to 250 lb live weight. The objective of this research was to evaluate the precision of the protein accretion curves and lysine requirements by quantifying the sampling errors associated with the growth and predicted nutrient requirement curves.