Reproductive success in rainbow trout following parental transfer of 2,3,4,7,8‐pentachlorodibenzofuran

Abstract

AbstractBroods stock rainbow trout were intraperitoneally injected with corn oil containing a nominal dose of 0 or 3 μg [14C]2,3,4,7,8‐pentachlorodibenzofuran (P5CDF)/kg (8.8 nmol/kg). The fish were held on a light cycle designed to induce spawning 10 months later. Eggs were expressed from individual ripe females and divided into two lots. One lot from each control female (Fc) and treated female (Ft) was fertilized by a treated male (Mt) and the other by a control male (Mc). Radioactivity levels were determined in parental muscle, gonads, eggs, embryos, and fry. Mean concentrations in dorsal muscle tissue were 604 pg/g (1.77 pmol/g) in treated females (Ft) and 868 pg/g (2.54 pmol/g) in treated males. No differences were found between treated and control fish, in fecundity, or in fertilization rates between any of the crosses. Concentrations of P5CDF in eggs at the time of spawning ranged from 68 to 443 pg/g wet weight with a mean concentration (N = 7) of 232 pg/g (0.68 pmol/g). Average prehatch mortalities, posthatch survival, or survival through swim‐up, and the first 21 d of feeding were not different between the cross groups. Within the Ft × Mt cross group, fertilization mortality, prehatch mortality, and total mortality were significantly correlated with egg concentrations of P5CDF. Marginal but significant increases in the incidence of blue‐sac‐like disease occurred in the groups from treated females.