Growth and Clinical Variables in Nitrogen-Restricted Piglets Fed an Adjusted Essential Amino Acid Mix: Effects of Partially Intact Protein-Based Diets.

Abstract

Background:

Current recommendations for protein levels in infant formula are intended to ensure that growth matches or exceeds growth of breastfed infants, but may provide a surplus of amino acids (AAs). Recent infant studies with AA-based formulas support specific adjustment of the essential amino acid (EAA) composition allowing for potential lowering of total protein levels. With the use of a combination of intact protein and free EAAs, we designed a formula that meets these adjusted EAA requirements for infants.

Objective:

Our objective was to test whether this adjusted formula is safe and supports growth in a protein-restricted piglet model, and whether it shows better growth than an isonitrogenous formula based on free AAs.

Methods:

Term piglets (Landrace × Yorkshire × Duroc, n = 72) were fed 1 of 4 isoenergetic formulas containing 70% intact protein and 30% of an EAA mixture or a complete AA-based control for 20 d: standard formula (ST-100), ST-100 with 25% reduction in proteinaceous nitrogen (ST-75), ST-75 with an adjusted EAA composition (O-75), or a diet as O-75, given as a complete AA-based diet (O-75AA).

Results:

After an initial adaptation period, ST-75 and O-75 pigs showed similar growth rates, both lower than ST-100 pigs (∼25 compared with 31 g · kg-1 · d-1, respectively). The O-75AA pigs showed further reduced growth rate (15 g · kg-1 · d-1) and fat proportion (both P < 0.05, relative to O-75).

Conclusions:

Formula based partly on intact protein is superior to AA-based formula in this experimental setting. The 25% lower, but EAA-adjusted, partially intact protein-based formula resulted in similar weight gain with a concomitant increased AA catabolism, compared with the standard 25% lower standard formula in artificially reared, protein-restricted piglets. Further studies should investigate if and how the specific EAA adjustments that allow for lowering of total protein levels will affect growth and body composition development in formula-fed infants.

• Authors: Päivi S Worsøe, Per T Sangild, Johannes B van Goudoever, Berthold Koletzko, Eline M van der Beek, Marieke Abrahamse-Berkeveld, Douglas G Burrin, Bert J M van de Heijning, Thomas Thymann
• Journal: The Journal of nutrition (J Nutr) Vol. 148 Issue 7 Pg. 1118-1125 (07 01 2018) ISSN: 1541-6100 [Electronic] United States
• PMID: 29901723 (Publication Type: Clinical Trial, Veterinary, Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Amino Acids, Essential
• Dietary Proteins
• Nitrogen

Topics

• Amino Acids, Essential (administration & dosage)
• Animal Feed
• Animal Nutritional Physiological Phenomena
• Animals
• Body Composition
• Diet (veterinary)
• Dietary Proteins (administration & dosage)
• Dietary Supplements
• Female
• Nitrogen (administration & dosage)
• Random Allocation
• Swine (blood, growth & development)