Effects of diets on the contents of free amino acids and urea in the cocoon shell of the silkworm, Bombyx mori (Lepidoptera: Bombycidae)

agricultural chemicals amino acids animal animal developmental stages animales animals arthropode arthropode utile arthropods developmental stages diet dieta dietetica dietetics engrais etapas de desarrollo etapas del desarrollo animal fertilizantes nitrogenados fertilizers gusano de seda insecte insecte utile insectos insects invertebrados invertebrates lepidoptera nitrogen fertilizers nutrition organic compounds organic nitrogen compounds produit agrochimique pupae pupe silkworms useful arthropods useful insects