Lysine Requirement of the Finishing Pig for Maximum Rate of Gain and Efficiency

Abstract

Four trials involving 146 finishing pigs were conducted to determine the lysine requirement for rate of gain and feed efficiency. Graded levels of L-lysine HCl were added to a 13.3% protein corn-sesame meal diet containing 3,501 kcal metabolizable energy per kilogram. Levels of .35, .45, .55, .65 and .75% dietary lysine were studied in trials 1 through 3, while in trial 4 an .85% level was also included. Values for each criterion from the four trials were pooled and the lysine requirement was determined by the method of least squares. Estimated requirement, as a percent of the diet, for maximum daily gain was .48% whereas, for maximum gain/feed it was .62%. In a fifth trial, six finishing pigs were used in two 3 × 3 latin square designs to determine maximum nitrogen retention from diets containing .45, .55 and .65% lysine. As level of lysine increased, nitrogen retention increased, but at a decreasing rate. The rate of decrease was not sufficient for an accurate estimate of the requirement for maximum nitrogen retention.