Published in AgroLife Scientific Journal, Volume 3, Number 1
Written by Rodne NASTOVA, Natasha GJORGOVSKA, Vasil KOSTOV
Selenium is a microelement necessary for normal growth, development and reproduction. In our research on carp at intensive breeding, we followed up the effects of selenium supplementation on the activity of the selenoenzyme glutathione peroxidase (in erythrocytes and in liver) and type I deiodinase (in serum). The experiments were performed in experimental pools in the fish farm “Boshava” during 2010, by introduction of inorganic (sodium selenate) and organic selenium (selenium starter) in supplemental food for young carps (0+). That way, at the end of the experiment a statistically significant length and weight growth was noticed in the youngsters’ groups fed with selenium supplemented food, compared to the control group fed without selenium supplement. Low mortality in the pools where selenium enriched food was implemented must be particularly pointed out. Mortality in the control group was 17.5%, in the group with inorganic selenium supplement 12.3%, and in the group with organic selenium supplement only 0.7%. In laboratory conditions we followed up the influence of cadmium in water (1.5 mg/l) on the activity of the enzyme glutathione-S-transferase, an enzyme important in the biotransformation of various pollutants. The activity of this enzyme is in correlation with the activity of the selenium-dependent enzyme, glutathione peroxidase. In relation to the control group, in the groups supplemented with selenium an increase of glutathione peroxidase activity in erythrocytes and liver was found, with simultaneous decrease of glutathione-S-transferase activity in carps’ plasma and liver.