Ostrander et al : Behavior of Oncorhynchus mykiss exposed to benzo[a]pyrene 



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Table 1 



Emergence and upstream swimming behavior of rainbow trout and coho salmon, showing number of fish performing each behavior. 

 In each experiment 150 apparently healthy salmon or trout eggs (embryos) were buried 1 week prior to hatching. 



"Data from Ostrander et al. 1988. 



* Significantly different from control group at P<0.05, chi-square analysis. 

 "Significantly different from control group at P<0.001. chi-square analysis. 



B[a]P was not significantly different (x-, P<0.05) 

 from embryos treated with DMSO (solvent controls) or 

 filtered lake water controls (Table 1). In both replicates 

 more than 95% of B[a]P-exposed fish successfully 

 emerged. 



The two B[a]P-exposed groups, however, exhibited 

 a decreased tendency to orient upstream when com- 

 pared with DMSO or untreated controls (x~, P< 

 0.001). Normal upstream orientation observed among 

 emerged untreated and DMSO solvent controls was 

 75-83% of emerging alevins, while among B[a]P- 



treated groups less than 46% of the emerged alevins 

 reached the upstream compartment (Table 1). 



Measurements of total body length, dry weight, and 

 caudal, dorsal, pectoral, and anal fin heights are sum- 

 marized in Table 2. There were no significant differ- 

 ences in the morphology of upstream and downstream 

 fish or between respective groups when tested with a 

 one-way analysis of variance. 



