Effect of DHA and vitamin E feeding on quality of semen in rabbits

Docohexaenoic acid (DHA) and vitamin E (vE) enriched diets have been fed to male rabbits with the aim to improve semen production and quality. Fifty two rabbits have been randomly divided in 4 groups and fed ad lib from the 20th week of age one of the 4 following diets: A=control; B=control + 200mg vE/kg; C=control + 1.5% fish oil; D=control + 200 mg vE/kg and 1.5% fish oil. Semen production was controlled during two 4-weeks periods, from 25 to 28 and from 37 to 40 weeks of age. During each period, semen was collected weekly and two successive ejaculates/male were recorded before pooling per treatment on which the following parameters were measured: concentration (106/ml), motility (%), viability (%), sperm alpha- and delta-tocopherol (microgram/109), TBARS test (microgram MDA/109). Total sperm production and semen quality were not affected by dietary treatments. The sperm content of alpha-tocopherol was increased as a consequence of dietary higher supplementation of vitamin E; however no difference in susceptibility to oxidation was found between the control and the vitamin E rich spermatozoa. Also semen collected from the DHA fed group did not show higher susceptibility to oxidation.