Vitamin A stores, teratogenesis, and EROD activity in white sucker,Catostomus commersoni, from Rivière des Prairies near Montréal and a reference site

Abstract

White sucker, Catostomus commersoni, were sampled from the Rivière des Prairies in the vicinity of Montréal and the upper reaches of the Ottawa River in La Verendrye Park (reference site). Rivière des Prairies fish had lower liver retinol (p ≤ 0.0001) and retinyl palmitate (p ≤ 0.0001) concentrations than fish from the reference site. Rivière des Prairies females and males contained only 9.3 and 30%, respectively, of the vitamin A stores detected in reference fish. Age was an important variable. Covariance analysis revealed that the the rate of retinyl palmitate storage with age was higher (p ≤ 0.0001) for sucker at the reference site. Retinaldehyde was the major retinoid in eggs; however, concentrations were not different between the two sites. The prevalence of malformations was 1.49% among Rivière des Prairies larvae, greater (p ≤ 0.002) than that of the reference group. Eye deformities (i.e., anophthalmia, synopsia) were 11.8 times more prevalent in the Rivière des Prairies larvae. Ethoxyresorufin-O-deethylase (EROD) was greater (p ≤ 0.0003) in the Rivière des Prairies fish. Liver EROD activity in adult females was positively correlated (R = 0.81; p ≤ 0.0004) with the prevalence of deformities of their progeny. Semiquantitative results showed that embryo mortality also tended to increase with EROD activity.