title: Responses of laying hens to a low-protein diet supplemented with essential amino acids, L-glutamic acid and/or intact protein.
abstract: 1. Three sequential experiments, each lasting 8 weeks, were carried out on 576 singly-caged light hybrids. 2. In experiment 1 egg production was 84% using a conventional control diet, 61% with a basal low-protein diet, and 79% with the basal diet supplemented with 10 essential amino acids+L-glutamic acid (GA). 3. In experiment 2 supplementation with lysine and methionine (L+M) alone increased egg production significantly from 54 to 72%, compared with 83% with the conventional diet. 4. In experiment 3 egg production was 55% with the basal diet, 71% with the basal diet+L+M, 75% with a diet containing 141 g protein/kg+L+M, and 73% with the conventional diet. 5. In all three experiments supplementation with GA alone either gave no significant response or a depression in production. 6. Daily intakes of 1-24 g nitrogen as non-essential amino acids and 13 to 14 g total crude protein per bird resulted in good egg production. Supplementation of the basal diet with L+M resulted in a daily intake of 413 mg methionine/bird day which was considered adequate, and a daily intake of 710 mg lysine which was considered slightly inadequate.
mesh_terms: D000601:Amino Acids, Essential / Q000378:metabolism*; D000821:Animal Feed; D000818:Animals; D001835:Body Weight; D002645:Chickens / Q000378:metabolism* / Q000502:physiology; D004044:Dietary Proteins / Q000378:metabolism*; D004734:Energy Metabolism; D005260:Female; D005971:Glutamates / Q000378:metabolism*; D008239:Lysine / Q000378:metabolism; D008715:Methionine / Q000378:metabolism; D010058:Oviposition
chemical_list: D000601:Amino Acids, Essential; D004044:Dietary Proteins; D005971:Glutamates; D008715:Methionine; D008239:Lysine