Gonadal Disorder in the Thinlip Grey Mullet (Liza ramada, Risso 1827) as a Biomarker of Environmental Stress in Surface Waters (original) (raw)
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Ecotoxicology and Environmental Safety, 2013
The African sharptooth catfish (Clarias gariepinus) is indigenous to South Africa where it is commonly found in calm waters such as lakes, streams, rivers, swamps and floodplains. The males of this gonochoristic species can be readily distinguished from females via a distinct elongated urogenital papilla with a pointed tip, located just behind the anus. This structure is an androgen controlled secondary sexual characteristic and could potentially be affected by chemicals displaying endocrine disrupting properties during development. Results of previous studies on effects on papillae of different fish species indicated that these structures could be useful as bio-indicators of exposure due to alterations in the structures. This study investigated the occurrence of abnormal morphology in urogenital papillae compared to the macroscopic and microscopic structure of the gonads of presumed male or intersex catfish sampled from the Rietvlei and Marais dams in an urban nature reserve, due to exposure to endocrine disrupting chemicals (EDCs). Macroscopic observation of the UGP, gonad examination after laparotomy and histology were done. Gonadosomatic index (GSI) and Urogenital papilla length index (UGPLI) were determined for all fish collected. Mesenteric fat analyzed for selected alkylphenols and organochlorines showed high levels of especially nonylphenol indicating long term exposure to these chemicals due to bio-accumulation. The GSI indicated that fish with intersex gonads were probably feminized males. It was concluded that use of the UGP alone, without macroscopic and microscopic analyses of the gonads, could not effectively indicate exposure to EDCs.
Journal of Biology and Life Science, 2013
The present work aimed to study some aspect of the reproductive biology of the P. javanicus with emphasis on histopathology abnormalities of gonads and intersex problems. Fish samples of Puntius javanicus (local name:tawes) were collected from Mas River on the Surabaya downtown whereas highly pollution. Fishes were identified for morphological abnormality and gonad organs were evaluated. Histological preparation was done to observe the gonad condition. This report reveals that 20% male P. javanicus were found to be feminized on July 19, 2012 collection from that river. Some histological samples indicated the presence of testis-ova in fish gonad, which indicated the occurrence of intersex of this species. The above finding suggests that greater attention needs to be given to xenobiotic pollutants and endocrine disrupting chemicals problems.
The Grand River watershed in Ontario, Canada, receives and assimilates the outflow of 29 Municipal Wastewater Effluent (MWWE) discharges which is a mixture of domestic and industrial wastes. The purpose of this study was to investigate the cumulative impact of multiple sewage discharges on populations of wild fish. In field studies, responses of fish populations and individual fish responses in terms of growth (condition factor), reproduction (in vitro sex steroid production, gonadosomatic indices, histology [cellular development and intersex]) were assessed upstream and downstream of two municipal discharges. Fish [Greenside Darters Etheostoma blennioides and Rainbow Darters E. caeruleum] collected downstream of two municipal wastewater plants had the potential to have greater growth (longer and heavier) when compared to reference fish collections regardless of sex. Fish were not assimilating additional anthropogenic resources into energy storage (increased condition, liver somatic index). Impacts on ovarian development appeared to be minor with no differences in growth, steroid production or cellular development. Sewage exposed male fish were experiencing impairment in the capacity to produce testosterone and 11-ketotestosterone in vitro, and in cellular development (GSI, intersex). Male darters of both species collected in the upstream agricultural region demonstrated no evidence of intersex whereas our urban reference sites had incidence of intersex of up to 20%. Rates of intersex were elevated downstream of both sewage discharges studied (33% and>60%, respectively). Lower rates of intersex at the intermediate sites, and then increases downstream of second sewage discharge suggests that fish populations have to potential to recover prior to exposure to the second sewage effluent. Pre-spawning darters demonstrated dramatically higher incidence of intersex in the spring at both urban reference sites (33% and 50%, respectively), and increased more so downstream of the near-field and far-field exposure sites (60% and 100%, respectively). These findings suggest that the compounds released in STP effluents have a tendency to act on the male reproductive system. These effects may become more pronounced as projected human population growth will require the aquatic environment to assimilate an increasing amount of sewage waste.
Chemosphere, 2019
Pesticides are distributed to different degrees in surface water and sediment, thus, risks of toxicity and adverse impacts to physiology of resident species could be determined by their microhabitat (sub-habitat) associations, either water column or sediment. River Owan receives pesticide input from diffuse sources from adjacent farmlands. Surface water, sediment and fish samples [(Pelagic: Tilapia zilli (n=92) and benthic: Neochanna diversus (n=59), Clarias gariepinus (n=68)] were collected within the catchment area across seasons for 18-months (August 2016-January 2018) and measured for pesticide levels. Testicular and Ovarian tissue samples across the three species were also examined for pathological alterations. Individual pesticide concentrations in surface water and sediment exceeded international allowable limits, while concentration of pesticide residues in tissues of benthic species was higher compared to pelagic fish. Histopathological assessment revealed a higher incidence of ovarian disruption including atretic follicles, intersex and disorganization of ovarian structure in benthic (bottom-dwelling) fish (C. gariepinus and N. diversus) compared to pelagic (water-column) fish (T. zilli). Males benthic fish species also recorded more severe anomalies, compared to pelagic fish. The damages and anomalies observed in ovarian and testicular tissue indicate chronic responses to pollutant exposure, and implicates the elevation of pesticide concentrations in surface water and sediment above permissible limits. The higher incidence of anomalies recorded for benthic species compared to pelagic species, indicates greater risks of reproductive disruption and could be associated with the microhabitat preferences (water-column or sediment).
Italian Journal of Animal Science, 2016
The term intersex describes alterations in gonadal development with the simultaneous presence of male and female reproductive stages in the same gonad of a gonochoristic species. In coastal and estuarine environments, euryhaline fish living in polluted waters such as Mugilidae can frequently show these sexual anomalies. In this work, we analysed adult specimens of three species of euryhaline mullets (Chelon labrosus, Liza aurata and Mugil cephalus) from two Sardinian lagoons (Marcedd ı and San Teodoro) devoted to extensive aquacultural practices, in order to identify putative alterations in gonads and in gamete development. Overall, 13 of the 158 mullets examined (8.2%) were affected by gonadal disorders: four subjects (one C. labrosus, two L. aurata and one M. cephalus) exhibiting an intersex condition were found in the Marcedd ı lagoon and the other nine (five C. labrosus, two L. aurata and two M. cephalus) in the San Teodoro lagoon. Twelve of these gonads were classified as testis-ova (TOs) and one, belonging to a C. labrosus specimen, was a mixed gonadal tissue (MGT). Intersex condition was evaluated using an intersex index and all the recorded values showed a mild Ovotestis Severity Index (OSI). However, our findings suggest that fish gonadal disorders may be underestimated in extensive reared fish species, particularly in coastal brackish environments polluted by intensive agriculture and animal husbandry activities.
Environmental Toxicology and Chemistry, 2001
The toxicity and estrogenicity of a final treated municipal effluent was examined while flowing through a constructed wetland in north-central Texas, USA. Fish data were collected, and a baseline wetland characterization was performed to assess wetland treatment potential for these effluent properties. Vitellogenin (VTG), gonadosomatic index (GSI), hepatosomatic index (HSI), and secondary sexual characteristics were biomarkers used in fish models to assess aqueous estrogenicity. Biological indicators used to assess overall fish health included hematocrit and condition factor. Estrogenic nature of final sewage treatment works effluent was screened, concurrent with a three-week fish exposure, via gas chromatography/mass spectrometry for target estrogenic compounds, including 17-estradiol, ethynylestradiol, bisphenol A, nonylphenolic compounds, phthalates, and DDT. The VTG in Pimephales promelas was measured after exposure at four sites in a treatment wetland and was significantly elevated (p Ͻ 0.0001) in fish exposed at the inflow site. The GSIs were significantly less (␣ ϭ 0.001) at the inflow site. At wetland sites closest to the inflow, secondary sexual characteristics, tubercle numbers, and fatpad thickness were less (␣ ϭ 0.0001) than in laboratory controls. The HSIs and density of male breeding stripes were not significantly different from those of laboratory controls. However, elevated HSIs were found at the inflow site. Hematocrit and condition factors were both less (␣ ϭ 0.001) in effluent-exposed fish at wetland sites closer to the inflow than in control fish or fish further downstream. ). The current address of J.M. Hemming is Department of Biological Sciences, University of South Alabama, LSCB124, Mobile, AL 36688, USA.
Environmental Health Perspectives, 2005
In recent years there has been considerable concern over the ability of substances discharged into the environment to disrupt the normal endocrine function of wildlife. In particular, the apparent widespread feminization of male fish in rivers has received significant attention from regulators in the United Kingdom, the United States, Europe, and Japan. The U.K. and European epidemiological data sets have demonstrated that the occurrence of feminized fish is associated with effluent discharges and that the incidence and severity is positively correlated with the proportion of treated sewage effluent in receiving waters. Although weakly estrogenic substances may contribute to the overall effect, studies have concluded that steroid estrogens are the principal and most potent estrogenic components of domestic sewage. Extensive laboratory data sets confirm that steroid estrogens are capable of eliciting the effects observed in wild fish at concentrations that have been measured in effluents and in the environment. Based on evaluation of the available information, the Environment Agency (England and Wales) has concluded that the weight of evidence for endocrine disruption in fish is sufficient to develop a risk management strategy for estrogenically active effluents that discharge to the aquatic environment.