shanjing in the Aquarium of the Cologne Zoo, and we document the ontogenetic developmental stages and describe the larva for the first time. Here, we report on the first captive breeding of T. Consequently, data on the reproductive biology of T. Therefore, papers published before 1995, including those on reproductive biology, could not distinguish between these two close relatives. The overall results suggest that these captive pre-slaughter farm crocodiles exhibited responses to anthropogenic aquatic contaminants with potentially relevant consequences on key reproductive and endocrine pathways and these responses may be established as relevant species endocrine disruptor biomarkers of exposure and effects in this threatened species.Tylototriton shanjing Nussbaum, Brodie & Yang, 1995 was described as a distinct species hidden before under the widely distributed T.
Principal component analysis (PCA) produced significant grouping that revealed correlative relationships between reproductive/endocrine-disruptive variables and liver contaminant burden, that further relates to measured contaminants in the natural environment. On the other hand, plasma T and 11-KT levels were significantly higher in males, compared to female crocodiles. While hepatic ERα, Vtg, ZP mRNA and testosterone 6β-OHase, were equally expressed in female and male crocodiles, gonadal ERα mRNA and aromatase activity were significantly higher in females compared to male crocodiles. In addition, the percentage of banded eggs ranged between 10 and 19% during the period of 2009–2014 seasons. Overall, there is high and abnormal number (%) of infertile and banded eggs during the studied reproductive seasons, showing up to 57 and 34% of infertile eggs in the 014 seasons, respectively. Gonadal aromatase and hepatic testosterone metabolism (6β-hydroxylase (6β-OHase)) were analyzed using biochemical methods. Plasma estradiol-17β (E2), testosterone (T) and 11-ketotestosterone (11-KT) were analyzed using enzyme immunoassay. Hepatic transcript levels for vitellogenin ( Vtg), zona pellucida ( ZP) and ERα (also in gonads) were analyzed using real-time PCR. In the present study, the developmental (including fertility) and endocrine-disruptive effects in relation to chemical burden in male and female Nile crocodiles ( Crocodylus niloticus), from a commercial crocodile farm in the Brits district, South Africa, exposed to various anthropogenic aquatic contaminants from the natural environment was investigated.
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