Evaluation of Fertilizing Capacity of Rabbit Sperm on the Basis of Annexin V-labelled Membrane Changes

The aim of this study was (1) to analy�e fresh intact or differently influenced rabbit sperm samples, using Annexin V–binding method for the detection of membrane phosphatidylserine translocation, and (2) to estimate obtained results in relation to the conceptional rate of rabbit females fertili�ed with semen from different groups. Following sample groups were designed: 1. freshly collected semen; 2. semen after 90 min incubation in sperm diluent; 3. semen incubated in cryoprotective medium, without free�ing; 4. semen fro�en in floating chamber with liquid nitrogen; 5. Semen fro�en using classical procedure in manual regime. Higher rate of annexin V-positive (AnV+) cells was observed in both cryopreserved groups (4, 5) when compared with groups 1, 2 and 3 (p< 0.05). The highest conceptional rate of rabbit females was obtained, when semen doses from groups 3, 2 or 1 were used for the insemination. Oppositely, conceptional rate was minimal when sperm was fro�en in floating chamber (group 4; 16.67%), whilst using the sperm fro�en in manual regime (group 5) no one of 13 inseminated females was parturited. A negative linear dependence between the rate of An-V+ cells and female conceptional rate was found. Therefore, Annexin V-labelling would be considered as a technique of choice to predict fertili�ing capacity of rabbit sperm.