Combined effects of high environmental ammonia, starvation and exercise on hormonal and ion-regulatory response in goldfish (Carassius auratus L.)

The Neuroendocrine Regulation of Food Intake in Fish: A Review of Current Knowledge

“…In Amur sturgeon, Acipenser schrenckii (Acipenseriforme), lower serum levels of thyroid hormones are seen in fish placed in high-density groups who display low feeding rates (Li et al, 2012). However, decreases in plasma levels of thyroid hormones are seen in fasted goldfish [T 3 ] (Sinha et al, 2012) and in fasted channel catfish [T 4 and T 3 ] (Gaylord et al, 2001), suggesting that food deprivation might decrease the activity of the HPT at the level of thyroid hormone synthesis and secretion, similar to what is observed in mammals (Boelen et al, 2008). A decrease in circulating thyroid hormones might inhibit the thyroid hormone negative feedback action on hypothalamic cells and contribute to the increase in hypothalamic TRH expression levels seen in goldfish.…”

Deiodinases and thyroid metabolism disruption in teleost fish

“…The HPT axis is sensitive to several physical environmental factors (Dhanasiri et al, 2013;Li et al, 2012;Little et al, 2013), which may modulate the pathway in different ways depending on whether they act alone or in combination (Sinha et al, 2012). Salinity, water flow, food intake, light period, temperature and stress are some of the most relevant factors known to alter deiodination (Table 1).…”

High environmental ammonia elicits differential oxidative stress and antioxidant responses in five different organs of a model estuarine teleost ( Dicentrarchus labrax )

“…High environmental ammonia (HEA) is a worldwide concern as it may affect the performance of fish in several ways. HEA induces a range of ecotoxicological effects in fish, including a decrease in growth rate (Dosdat et al, 2003;Sinha et al, 2012a), alteration in energy metabolism (Arillo et al, 1981;Sinha et al, 2012aSinha et al, , 2015, disruption of ionic balance (Wilkie, 1997;Sinha et al, 2012bSinha et al, , 2014aSinha et al, , 2015Diricx et al, 2013), alterations in hormone regulation (Knoph and Olsen, 1994;Dosdat et al, 2003), increase vulnerability to diseases, and even mortality. To protect against ammonia toxicity, various defensive strategies have been reported in freshwater and marine teleosts (Ip et al, 2001(Ip et al, , 2004a.…”