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<br />o <br />c, <br /><"=- <br />I~ <br />..::- <br />o <br /> <br />Progeny <br /> <br />., <br />I <br />I <br />I <br /> <br />Hatchability and abnormalities <br /> <br />Hatchability for eight of the 10 spawns was 87% or higher and averaged about 84% <br /> <br />across all spawns (Table 9). The low hatchability of 43% for eggs produced by female 4B-31 <br /> <br />was due primarily to a fungal infection that occurred in all four egg cups at 4 days postspawn. <br /> <br />" <br />" <br />1 <br /> <br />Average time to hatch ranged from 4.2 to 4.7 days and over 99% of the eggs hatched at 4 or 5 <br /> <br />days postspawn. Survival ofthe resulting larvae during the hatching period was greater than <br /> <br />95%. There were no significant correlations among hatchability, time to hatch, larval survival, <br /> <br />, <br />., I <br />, <br />I <br /> <br />and adult selenium exposure concentrations. Moreover, hatchability was not correlated with <br /> <br />number of eggs per female or size of the eggs. <br /> <br />The incidence oflarvae with abnormalities ranged [rom 7.0 to 19.3% and was not <br /> <br />correlated with adult selenium exposure, hatchability, or larval survival (Table 9). The lowest <br /> <br />incidence of abnormalities occurred in larvae hatched from the group of eggs infected with <br /> <br />fungus. This observation indicated that embryos with deformities may have been more sensitive <br /> <br />than normal embryos to the fungus infection. The most commonly observed abnormalities were <br /> <br />scoliosis (lateral curvature of spine) and cardiac edema, which occurred in 9.4 and 6.2% of the <br /> <br />larvae, respectively. Other abnormalities observed (% occurrence in larvae) included abdominal <br /> <br />edema (1.5%), microcephaly (abnormally small head, 1.5%), microphthalmia (abnormally small <br /> <br />".-' <br /> <br />eyes, 1.I%), and kyphosis (dorsal curvature of spine, 0.7%). <br /> <br />Larval survival and growth <br /> <br />Survival oflarvae after 30 days ranged from about 73 to 98% and averaged about 87% <br /> <br />across all spawns (Table 10). Most of the mortalities (62% of all mortalities) occurred within 5 <br /> <br />38 <br />