L-Lysine is the reference amino acid in modern animal nutrition.
It must be provided in all types of animal feed to ensure optimal performance.
Especially, L-lysine is an essential amino acid for monogastric animals.
It cannot be synthesized by the organism and needs to be provided with the feed.
Therefore, supplementation of free L-lysine is the 1st limiting amino acid in swine feed
and the 2nd limiting amino acid in broiler feed and aquatic animal feed.
(The order of limiting amino acids can differ depending on environment or feed ingredients.)
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