Iodine-enriched rotifers and Artemia prevent goitre in Senegalese sole (Solea senegalensis) larvae reared in a recirculation system

Iodine and selenium supplementation increased survival and changed thyroid hormone status in Senegalese sole (Solea senegalensis) larvae reared in a recirculation system

“…This is in accordance with previous studies where T 4 levels increased due to iodine-rich water (Witt et al 2009) or iodine-enriched diets (Ribeiro et al 2009;Moren et al, unpublished), but where the T 3 levels were not affected. T 3 is the most bioactive and potent thyroid hormone and its level in the tissues is closely regulated (Eales and Brown 1993).…”

“…Hence, the thyroid follicles are continuously stimulated to grow and multiply to produce more T 4 , which is not possible. Ribeiro et al (2009) demonstrated that goitrous S. Sole grew less than larvae given extra iodine. This was not seen in the present study despite the development of goitre in the control larvae.…”

“…Se). To achieve these diets, three different Artemia enrichments were prepared as previously described by Ribeiro et al (2010) and by Ribeiro et al (2009), with DHA Selco (Inve Aquaculture NV, Belgium) (C), DHA Selco and NaI (I) and DHA Selco, NaI and Sel-Plex Ò (I ? Se), a selenized yeast (Sel-Plex Ò , Alltech Inc Brazil) where most of the selenium exists in the form of seleno-methionine (Encinar et al 2003).…”

“…Ozone contact chambers have a powerful oxidation-reduction potential (Sherrill et al 2004), altering the water concentration of iodide (I -) by converting it into iodate (IO 3 -) (Bichsel and von Gunten 1999;Sherrill et al 2004). Fish reared in iodide-depleted water, fed diets low or deficient in iodine may develop thyroid hyperplasia (Sherrill et al 2004), but when the larvae were fed extra iodine through their diet, the follicles developed normally (Ribeiro et al 2009). Ribeiro et al (2009) found that Senegalese sole larvae developed hyperplasia and goitre when reared in a recirculation system with ozone injection.…”

“…Fish reared in iodide-depleted water, fed diets low or deficient in iodine may develop thyroid hyperplasia (Sherrill et al 2004), but when the larvae were fed extra iodine through their diet, the follicles developed normally (Ribeiro et al 2009). Ribeiro et al (2009) found that Senegalese sole larvae developed hyperplasia and goitre when reared in a recirculation system with ozone injection. When the larvae were fed extra iodine, the follicles developed normally.…”