Sexual Disruption in a Second Species of Wild Cyprinid Fish (The Gudgeon, Gobio Gobio) in United Kingdom Freshwaters

Abstract

To establish whether the intersex condition seen in the roach (Rutilus rutilus) in United Kingdom (UK) rivers was species specific or a more general phenomenon in fish, evidence for sexual disruption was sought in a second cyprinid species, the gudgeon (Gobio gobio). Gudgeon were collected from the Rivers Aire and Lea (at locations that receive high-volume discharges of sewage treatment works [STW] effluent and that contain intersex roach) and from two still waters, and their gonads were examined histologically for evidence of intersexuality (the simultaneous presence of oocytes and testicular tissue). Intersex gonads were found at all sites, with the highest incidences occurring at one of the still waters (Lakeside Fisheries: 15%) and at sites on the River Aire (Thwaite Weir, Silsden Bridge, and Knostrop: 14, 13, and 12%, respectively). In the River Lea and Longton Park Lake, the incidence of intersexuality in gudgeon was 6%. In most cases, intersex gonads were characterized by a few primary oocytes/gonad section in an otherwise normal testis. However, at some sites on the River Aire (Thwaite Weir and Knostrop), the intersex condition was more severe. At Thwaite Weir, for example, more than half of the gonad in 40% of the intersex fish was comprised of ovarian tissue. Elevated concentrations of plasma vitellogenin both in male and in intersex fish indicated that fish had been exposed to estrogen(s). Some of the gudgeon were found at sites several kilometers downstream of any point discharge of STW effluent; therefore, the results likely are representative of this species in wild populations found in typical UK river ecosystems. Together with the findings in the roach, these data on the gudgeon confirm that sexual disruption in fish in UK rivers is not species specific.

The use of the urogenital papillae of male feral African sharptooth catfish (Clarias gariepinus) as indicator of exposure to estrogenic chemicals in two polluted dams in an urban nature reserve, Gauteng, South Africa

“…The GSI values for males determined in this study were similar to those reported by Barnhoorn et al (2004), where the GSI values for intersex catfish collected were in a closer range to the male GSI values than to females. These suggested that the intersex fish could be the result of feminization of male sharptooth catfish, similar to the observation of van Aerle et al (2001) in Gobio gobio specimens collected from rivers in the U.K., downstream of a sewage treatment facility.…”

“…The gonadal somatic index (GSI) was calculated according to the equation: gonadal weight/ (body weight-gonadal weight) Â 100 (van Aerle et al, 2001). The GSI is a somatic index that is frequently used for assessing the health and reproductive status or maturity of fish (De Vlaming, 1981).…”

Long-term exposure investigating the estrogenic potency of estriol in Japanese medaka (Oryzias latipes)

“…In our previous work, we also found that β-estradiol 17-valerate (EV) at 1 ng/L can induce feminization and affect normal development of medaka (Oryzias latipes) (Lei et al, 2013a). Several field studies have also shown that these adverse reproduction and development responses in wild fish may be due to chemicals present in aquatic environments (Van Aerle et al, 2001;Jobling et al, 2006;Lange et al, 2011;Yan et al, 2012) and are related to reproductive failure in fish (Nash et al, 2004).…”

Horizontal and Vertical Distribution of Estrogenic Activities in Sediments and Waters from Tokyo Bay, Japan

“…Estrogens induce vitellogenin, a precursor protein for egg yolk that has been used as a sensitive biomarker for studies of xenoestrogens in aquatic environments (Harries et al 1997;Allen et al 1999aAllen et al , 1999bMinier et al 2000;Simpson et al 2000;Oberdçrster and Cheek 2001;van Aerle et al 2001). We previously found vitellogenin induction and intersex gonads, two bioindicators of the effects of environmental estrogens, in male flounder, Pleuronectes yokohamae, collected from Tokyo Bay, Japan (Hashimoto et al 1998b.…”