Solexa Sequencing of MicroRNAs on Chromium Metabolism in Broiler Chicks

Aim: The aim of this study was to determine the effect of chromium picolinate (CrPic) on the differential expression of the known microRNAs (miRNAs) in broiler skeletal muscle. Methods and Results: A total of 288 1-day-old male Arbor Acres broilers were randomly assigned to one of four dietary treatments supplemented with 0, 0.4, 2.0, or 10.0 mg.kg(-1) CrPic, respectively. Dietary CrPic supplementation at 10.0 mg.kg(-1) increased the average daily feed intake in broilers (p < 0.05). On day 42, the serum total protein level was highest in animals treated with 2.0 mg.kg(-1) (p < 0.05) and 10.0 mg.kg(-1) CrPic (p < 0.05). Dietary supplementation with 10.0 mg.kg(-1) CrPic decreased the levels of serum glucose (p < 0.05) on day 42 and of serum triglyceride (p < 0.05) on days 21 and 42. To further identify miRNAs from broiler skeletal muscles, we sequenced two small RNA libraries using the Solexa sequencing approach, and 57 miRNAs were found to be significantly differentially expressed (p < 0.05). Among them, 6 upregulated and 2 downregulated miRNAs were validated by real-time qPCR (p < 0.05). Conclusions:The results of the present study provide a valuable clue regarding the role of miRNA target genes in the mechanism of the dietary CrPic effect on protein synthesis in skeletal muscles of broilers. (C) 2013 S. Karger AG, Basel