Here are the answers to the questions:

1. What tool was used for pathway enrichment analysis?
**Ingenuity Pathway Analysis (IPA)**

2. Was a tool version number provided?
**Not described**

3. What gene set library was queried (eg: GO, KEGG, Reactome or other)?
**Not described**

4. Was a background gene list defined for pathway enrichment analysis?
**Not described**

5. What statistical test was used for enrichment analysis?
**Not described**, but the article mentions that Genespring was used to identify differentially expressed transcripts and IPA was applied to recognize gene pathways associated with vitamin A supplementation, and Kruskal-Wallis test was used to determine significant changes in gene expression.

6. Was false discovery rate correction used to control the number of false positives in the pathway enrichment analysis?
**Not described**

Let me know if you'd like me to help with anything else!