Effect of extenders and some additives on survival and morphology of spermatozoa in ram semen

A number of authors present in their works the significance of adding various additives into extenders, mainly before freezing the spermatozoa. Various purified lipid preparations, butyled hydroxytoluenes, sugar alcohols - alditols, as well as many other hydrophilic polymers - fermentation gum, polyethylene glycol and polyvynylpyrrolidone were added (Parks et al., 1981; Graham and Foote, 1987; Graham and Hammerstedt, 1992; Parks and Graham, 1992). Many non-penetrating sugars, like saccharose and trehalose, which stabilize liposomal membranes (Anchordogery et al., 1987) can be used. The works point out that a combination of lipids and agents stabilizing the membranes are necessary to stabilize the whole cell membrane of spermatozoon. We used the knowledge of a number of authors in the tests of extenders with additives. Paulenz et al. (2002) studied the effects of four different extenders (lactic, citrate-sodium on the base of Tris with fructose, citric acid, mixed with egg yolk, and commercial Tris extender supplemented with egg yolk) that influence the viability of spermatozoa in ram semen. Results show clearly the advantages of extenders on Tris base, the motility of sperms being significantly higher with them compared with lactic or natrium-citrate ones. Ram semen treated with the commerce extender on Tris base keeps the motility of sperms for longer time. The objective of our work was to test the effect of extenders and some additives on fertilizing capacity of ram semen in laboratory conditions. We checked up commercial extenders as well as extenders we prepared according to precise prescriptions, adding some additives to them. On the fifth day of long-running thermo-resistance test we noticed 42 % activity and only 9 % abnormal sperms under the influence of morphological changes using the Triladyl extender and Caffeine additive. In the control sample was used the Triladyl extender without additive and we noticed 21 % activity of sperms and morphological changes were within norm. We noticed also with other extenders used with Caffeine additive the highest motility on the fith day of test compared with the control sample. On the basis of laboratory analyses of the long-running thermo-resistance test we can state that additives affect positively the survival of sperms.