Effects of high nutrient intake on the growth performance, intestinal morphology and immune function of neonatal intra-uterine growth-retarded pigs.

摘要

Intra-uterine growth-retarded (IUGR) neonates have shown an impairment of postnatal intestinal development and function. We hypothesised that the immune function of IUGR neonates might be affected by increased nutrient intake (NI) during the suckling period. Therefore, we investigated the effects of high NI (HNI) on the growth performance, intestinal morphology and immunological response of IUGR and normal-birth weight (NBW) piglets. A total of twelve pairs of IUGR and NBW piglets (7 d old) were randomly assigned to two different nutrient-level formula milk groups. After 21 d of rearing, growth performance, the composition of peripheral leucocytes, serum cytokines and intestinal innate immune-related genes involved in the Toll-like receptor (TLR)-4-myeloid differentiation factor 88-NF- kappaB pathway were determined. The results indicated that IUGR decreased the average daily DM intake (ADMI) and the average daily growth (ADG). However, the ADMI and ADG were increased by HNI, irrespective of body weight. Likewise, serum cytokines (TNF- alpha and IL-1 beta) and ileal gene expressions (TLR-4, TLR-9, TRAF-6 and IL-1 beta) were lower in IUGR piglets, whereas HNI significantly increased blood lymphocyte percentage and serum IL-10 concentrations, but decreased neutrophil percentage, serum IL-1 beta concentrations and ileal gene expressions (NF- kappaB and IL-1 beta). Furthermore, IUGR piglets with HNI exhibited lower serum concentrations of TNF- alpha and IL-1 beta than NBW piglets, and these alterations in the immune traits of IUGR piglets receiving HNI were accompanied by decreasing ileal gene expressions of TLR-4, TLR-9, NF- kappaB and IL-1 beta that are related to innate immunity. In conclusion, the present findings suggest that increased NI during the suckling period impaired the immune function of neonatal piglets with IUGR