The Effect of Dietary Supplementation with Organic and Inorganic Selenium on Quality of Frozen-Thawed Semen in Broiler Breeder Cockerel under Oxidative Stress with Dexamethasone

The present study was performed to investigate the effects of dietary organic and inorganic selenium on the quality of frozen-thawed semen of broiler breeder cockerel under oxidative stress. In this experiment, a total of 24, 28-week-old Ross 308 cockerels were allocated into 4 treatments each of which had 6 birds, in a completely randomized design. Experimental groups were: 1) control group (CON): basal diet without selenium supplementation or dexamethasone administration, 2) DEX group: birds consumed the basal diet with dexamethasone injection (4 mg/Kg body weight, three times, every other day for 1 week), 3) DEX(OSe) group: addition of 0.3 mg selenium per kilogram of diet from selenomethionine as organic selenium to the basal diet of birds administrated dexamethasone like group 2 and 4) DEX(ISe) group: similar to group 3 but selenite sodium as an inorganic source was added to the diet. After semen collection, the semen was frozen by modified Beltsvile extender. Sperm evaluation was carried out by the Computer-Assisted Sperm Analysis system (CASA) in thawed semen. Results showed that the addition of organic selenium to the diet of stressed birds (DEX(OSe)) improved total and progressive motility versus other experimental groups (P<0.05); although, DEX(OSe) was not statistically different with CON in progressive motility (P>0.05). Also, the addition of inorganic selenium in the diet of stressed birds (DEX(ISe)) did not improve the mentioned parameters versus DEX (P>0.05). On the other hand, not only the viability and membrane integrity of sperm but also biochemical parameters (glutathione peroxidase and superoxide dismutase) of DEX(OSe) were higher than other experimental groups (P<0.05). It seems, the addition of organic selenium in the diet of cockerel under physiologic stress results in higher sperm quality than inorganic selenium.