CAFFEINE AS SEMEN ADDITIVE TO IMPROVE POOR MOTILITY OF SPERMS CRYOPRESERVED IN LIQUID NITROGEN FOR HOLSTEIN BULLS BORN IN IRAQ

Abstract

In an attempt to find a suitable media including caffeine as semen diluent to improve semen quality during frozen storage in liquid nitrogen up to 48 hr.’s, this study was conducted. A total of 32 ejaculate collected by artificial vagina from. eight Holstein Friesian bulls born in Iraq which have same ages, theejaculates, which have individual motility more than 40% dilution with tris and the diluted semen was divided into four aliquots including control and three experimental groups. Each aliquot was further diluted with an equal volume of a tris based extender without addition (control) or containing 0.5mM/ml (T1), 1mM/ml (T2) and 1.5 mM/ml (T3) caffeine. All diluted semen cooled to 5°C and evaluation (individual motility%, dead%, abnormality% and acrosome defect%), filling in mini straws and frozen in liquid nitrogen, after 48hr of storage, thawing frozen semen in 37°C for 30 sec and evaluated same physical properties, which done after dilution semen. Results revealed that individual motility percentage in T3 more significant (P<0.05) than control and other treatment T1 and T2, but dead and abnormality sperms percentage decreased significant (P<0.05) in treated T3 compare with control, T1 and T2. Moreover, all treatment (T1, T2 and T3) showed significant decrease (P<0.05) in acrosome defect compared with control. In addition to the present study shown that freezing step caused significantly increase (P<0.05) indead%, abnormality% and acrosome defect%. Based on this study, it wasconcluded that addition of 5 mM of caffeine to the extender improved the motility of spermatozoa% but decrease dead%, abnormality% and acrosome defect% compared to the controls and others concentration during cooling and post freezing in liquid nitrogen storage.