Spermatogenesis, hormonal fluctuations, and testicular gene expression changes in male blue catfish, Ictalurus furcatus, throughout pubescent and early adult stages of development

Male blue catfish (Ictalurus furcatus) mature at 4-7 years and cannot be hand-stripped, making sperm collection a lethal procedure. Sperm are also highly variable in quality/quantity. Therefore, establishing links between seasonality, aging, and reproductive success is essential. Since there are no prior studies regarding seasonal and age-related changes in the testis transcriptome of male blue catfish, we evaluated global gene expression in testicular tissue over a 34-month period (2.3 to 4.9 years old; y/o). Significant differential expressed genes and gene ontology of pairwise comparisons are presented and discussed. Overall design: A total of 15 testis tissue samples from blue catfish males were used in this study, corresponding to ages 2.9, 3.1, 3.9 and 4.2. Three-four testis tissue samples were collected per age group and extracted for RNA-seq.