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<br />Spawning Trials <br /> <br />~, After water temperatures reached 200e (day] 35 of study), five males were examined for <br />';-j <br />:--~ <br />,,:. spawning characteristics. Four of them had developed tubercles on the head, operculars, and <br />I-~ <br />C~). pelvic fins, The tuberculated males were checked for the presence of milt, but none of them <br /> <br />expressed a milky fluid, By day 140 of study, all of the males had tubercles and over 25% of <br /> <br />them expressed a milky fluid when handled. On day 144 of study, 16 females were examined <br /> <br />and all of them had acquired tubercles on the head and their abdominal region appeared to be <br /> <br />distended. On day 153, all adults were examined by the Assistant Manager, DNFH, for <br /> <br />spawning characteristics and over one-half of the females appeared to be in condition for <br /> <br />ovulation if given a hormone injection (R. Hamman, U.S, Fish and Wildlife Service, written <br /> <br />communication). Consequently, the decision was made to induce spav,ning by hormone <br /> <br />injection (described below). <br /> <br />Spawning trials occurred on days 154 and 155 of study. Females that did not express <br /> <br />eggs on day 154 were checked for ripeness on day 155 and females that did not release eggs after <br /> <br />the second spawning trial were considered to be nonspawners. No further attempts were made to <br /> <br />induce ovulation in the nonspawning females because they were judged to be incapable of <br /> <br />spawning this year (R. Hamman, U.S. Fish and Wildlife Serviee, written communication). After <br /> <br />the spawning trials were completed, the selenium treatments were discontinued and the <br /> <br />depuration period began. <br /> <br />The procedures used to spawn the fish followed those of Hamman (1981). Briefly, on <br /> <br />day 153 of the study, all males were injected intraperitoneal (IF) with human chorionic <br /> <br />gonadotropin hormone (Chorex, Hyrex Pharmaceuticals, Memphis, TN) at 660 IU/kg body <br /> <br />weight and all females were injected IP with carp pituitary (Stoller Fisheries, Spirit Lake, lA) at <br /> <br />14 <br />