Metabolic Alterations in Crassostrea Gigas After Feeding Selenium-Enriched Yeast Based on Transcriptomic Analysis

This study explores the effects of selenium-enriched yeast supplementation on growth-related and immune-related gene expression in <i>C. gigas</i>, aiming to support feed optimization in oyster aquaculture. Selenium, an essential trace element, is vital for growth, immune function, and metabolism in animals. Selenium-enriched yeast, an organic form, offers superior bioavailability, enabling efficient absorption and utilization. <i>C. gigas</i>, a commercially significant marine shellfish, is rich in protein and nutrients, but the effects of selenium on mollusks remain insufficiently explored. In this study, oysters were divided into three groups: a control group without selenium (THNP), a 2 ppm selenium group (THMP), and a 4 ppm selenium group (THHP). Transcriptome sequencing yielded 388,679,026 clean reads. GO and KEGG enrichment analyses identified key metabolic signaling pathways, and a PPI analysis was performed on the translation products of DEGs involved in the KEGG pathways. qRT-PCR validated the expression of principal DEGs. The combined results of enrichment and PPI analyses highlighted pathways such as glutathione metabolism and collagen signaling. Additionally, three hub genes-<i>FASN</i>, <i>HRAS</i>, and <i>ABCG5</i>-were identified as central to the selenium response. These findings enhance the understanding of selenium's molecular impact on oysters and support its application in aquaculture.