Lysine lysine is restrictive amino acid in pig feed. In the animal protein feed and lysine content in soybean cake meal is more, the rest of the plant protein feed containing lysine is low. National standard L - lysine hydrochloride for yellow or light brown powder, odorless or micro special smell, easily soluble in water. In the absence of animal protein feed and soybean cake meal, adding lysine in order to improve the production performance of pigs and the feed efficiency.