Impact of normal or low organic mineral (Cu, Zn, Mn) diets on gene expression patterns in the intestine of broiler chicks

Abstract

We assessed the impact of early life mineral (Zn, Cu, Mn) nutrition on gene expression in the jejunum. Broiler chicks were randomly assigned to 1 of 3 treatments. Corn‐soy diets had organic Zn, Cu, and Mn (BioPlex®, Alltech Inc.) at 100% (normal, N) or 20% (low, L) of NRC requirements. Diets were fed for 5 d, followed by a second diet (d 6–21), creating 3 groups: N‐N, N‐L, or L‐L. On d 21, birds were euthanized and gene expression was analyzed using the Affymetrix Chicken Genome Array. Compared to N‐N, the number of genes significantly changed was 303 for N‐L and 530 for L‐L, with 154 commonly affected. Both N‐L and L‐L led to down‐regulation of genes metallothionein 3 and 4 compared to N‐N. Gene ontology (GO) classifications showed that L‐L had a greater impact than N‐L on genes associated with metal ion transport, Zn ion binding and carbohydrate metabolic processes. IPA analysis showed the top biologic functions affected by N‐L were cell signaling, cellular function and maintenance, and cell morphology; for L‐L they were protein synthesis, cell death and post‐translational modification. Although both groups were fed the same diet d 6 – 21, IL‐17A pathways were enriched with L‐L only. Thus, mineral levels up to 5 d of life altered gene expression in birds on d 21, suggesting that early nutrition has a significant, long term impact on gene response in the intestine of young chickens.