Association of vitamin e with rapid thawing on goat semen

Abstract

The aim of this study was to evaluate the effects of vitamin E associated with rapid thawing on cryopreserved goat semen. Two bucks were used and eight ejaculates per animal were collected using artificial vagina. Semen was diluted with the following treatments: BIOXCELL (control), BIOXCELL + Equex (sodium lauryl sulphate) and BIOXCELL + vitamin E 100 μM. Semen was packaged into 0.25 mL straws and cooled at 5 ∘ C for 1 hour. Freezing was performed in liquid nitrogen vapor (−155 ∘ C) during 15 minutes. Then, the straws were immersed in liquid nitrogen (−196 ∘ C). Straws were thawed at 38 ∘ C/60 seconds or at 60 ∘ C/7 seconds with immediate sperm analysis. Hypoosmotic swelling test was performed adding a 20 μL aliquot of thawed semen to 1 mL of hypoosmotic solution (100 mOsm⋅Kg −1 ) followed by incubation during 60 minutes in water bath (38 ∘ C). Vitamin E did not affect any studied parameters (P > 0.05). Nevertheless, defrosting rate of 60 ∘ C/7 seconds improved sperm membrane functional integrity (P < 0.05). Current knowledge about goat semen cryopreservation is not sufficient to ensure high post-thawing recovery rates; thus, this study brings important data about using antioxidants and different thawing rates on cryopreservation process.