Location: Children's Nutrition Research CenterTitle: Feeding modality affects muscle protein deposition by influencing protein synthesis, but not degradation in muscle of neonatal pigs Author
Submitted to: Journal of Animal Science Supplement
Publication Type: Abstract Only
Publication Acceptance Date: 2/15/2011
Publication Date: 7/10/2011
Citation: El-Kadi, S.W., Suryawan, A., Gazzaneo, M.C., Orellana, R.A., Srivastava, N., Nguyen, H.V., Murgas-Torrazza, R., Lobley, G.E., Davis, T.A. 2011. Feeding modality affects muscle protein deposition by influencing protein synthesis, but not degradation in muscle of neonatal pigs [abstract]. In: Proceedings of the American Dairy Science Association and the American Society of Animal Science Annual Conference, Session: Nonruminant Nutrition: Amino Acids, New Orleans, Louisiana, July 10-14, 2011. Journal of Animal Science Supplement. 89(E-Suppl. l) 393:442. Interpretive Summary:
Technical Abstract: Neonatal pigs can serve as dual-use models for nutrition research in animal agriculture and biomedical fields. To determine how feeding modality by either intermittent bolus or continuous schedule affects protein anabolism and catabolism, neonatal pigs (n = 6/group, 9-d-old) were overnight fasted (FAS) or fed continuously (CON) or intermittently (INT; 7 × 4 h meals) for 28h. During the last 8 h, pigs were infused with [(2)H]phenylalanine and [(2)H]tyrosine and amino acid (AA) net balances were measured across the hindquarters for the last 4h. Glucose, insulin, branched-chain AA (BCAA), phenylalanine (Phe) and tyrosine (Tyr) arterial levels, and whole body Phe and Tyr rates of appearance were greater ("P" < 0.05) in INT after the meal, but not in the CON or FAS groups. Whole body Phe hydroxylation was greatest for INT ("P" < 0.05). Across the hindquarters, BCAA, Phe, and Tyr were net removed (different from zero, "P" < 0.05) for INT and CON, but not for FAS pigs. Hindquarters net protein deposition was stimulated following the meal for INT as compared with CON and FAS groups ("P" < 0.001). This was because protein synthesis increased following feeding for INT (P < 0.001), but remained unchanged for CON and FAS pigs, while no temporal changes in protein degradation occurred in any of the diet treatments. These results suggest that muscle protein accretion is enhanced with intermittent to a greater extent than continuous feeding, mainly by increasing protein synthesis.