Motility of sperm from adult largemouth bass pond exposure to 17 alpha-ethinylestradiol or estrone-atrazine mixture (2018)

Adult largemouth bass have been shown to be sensitive to induction of intersex in response to chronic estrogen exposures over a complete reproductive cycle. Late summer to fall is the period of early gonad recrudescence when spermatogenesis is beginning in preparation for the spawning season in the spring. Our objective was to assess in 2018 whether early gonad recrudescence was a period of sensitivity for induction of intersex and/or alterations in reproductive condition or function. Adult male largemouth bass were exposed in outdoor pond mesocosms from post-spawning to early gonad recrudescence to either 17alpha-ethinylestradiol or to a mixture of endocrine-active substances commonly detected in the Chesapeake Bay watershed (atrazine and estrone). Gonad samples were sent overnight to Wetland and Aquatic Research Center laboratories and sperm motility was measured by computer assisted sperm motion analysis. Overall, male reproductive condition, sperm count, and sperm motility were analyzed.