posted on 2025-03-04, 07:18authored byYuliang Wu, Yalu Yan, Xia Xiong, Rui Li, Sufang Duan, Mengxuan Tang, Ignatius Man-Yau Szeto, Hongnan Liu, Suzanne M. Hodgkinson, Paul J. Moughan, Philip Wescombe, Jianwu Wang, Yulong Yin
Breast
milk (BM) is the optimal nutrition source for infants, providing
highly digestible proteins. In contrast, the digestibility of proteins
in infant formula (IF) varies, influenced by differences in proteins
such as α-lactalbumin (α-La) and β-casein (β-CN).
This study aimed to evaluate the true ileal digestibility (TID) of
amino acids (AAs) in BM and IF with varying α-La and β-CN
contents using neonatal piglets. Twenty-four 11-day-old piglets (4
groups; 6 replicates/group) received either a nitrogen-free diet,
IF (high infant formula (HIF) with 1.74 g/100 α-La and 2.3 g/100
β-CN; low infant formula (LIF) with 1.07 g/100 α-La and
1.85 g/100 β-CN), or BM (1.82 g/100 α-La and 3.05 g/100
β-CN) for 7 days after 3 prefeed days. IF had higher concentrations
of nitrogen, serine, threonine, and proline than BM. Glutamic acid
was the most abundant AA in IF and BM, while methionine in BM and
LIF or tryptophan in HIF was the least. BM showed the highest TID
of AAs, with the LIF had the lowest. The HIF group’s TID for
AAs, especially tryptophan, was similar to BM and significantly better
than LIF. These results suggest that adjusting the α-La and
β-CN ratio in IF can improve AA digestibility, approaching BM
levels.