Evaluation of the acrosomal status in Lama glama sperm incubated with acrosome reaction inducers

M.I. CARRETERO; F. FUMUSO; D. NEILD; S. GIULIANO; P. CETICA; M. MIRAGAYA

ANIMAL REPRODUCTION SCIENCE

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2015 vol. 160 p. 1 - 11

0378-4320

The objectives of this study were to evaluate the effect of different acrosome reaction (AR) inducers on viability and acrosomal status in llama spermatozoa, by using the FITC-PNA/PI technique and evaluate if there is a positive correlation between the FITC-PNA/PI and the Coomassie blue (CB) staining techniques. After incubating twenty ejaculates in 0.1% collagenase the centrifuged pellets were resuspended in TALP-BSA medium. An aliquot was sonicated to remove the acrosomal content (positive control). The rest of the sample was incubated for 3h at 38°C with 5% CO2 and 100% humidity. Treatments: Three aliquots were further incubated 1h with one of the following AR inducers: calcium ionophore, ionomycin or progesterone. Controls: One without inducers and the other, incubated with dimethyl sulfoxide (vehicle of the inducing agents). Acrosomes were evaluated at time 0 and after 4h incubation. Calcium ionophore was the most potent agent for inducing the AR (67.2±14.4% live+dead AR sperm) (P<0.05). These samples showed no motility and viability was very low (0-30%). Both ionomycin and progesterone presented significantly higher (P<0.05) percentages of total AR sperm than the controls, but had similar percentages of dead reacted sperm to the controls. A positive correlation was observed between the intact acrosome FITC-PNA/PI pattern (live+dead sperm) and the acrosome-present CB pattern (r=0.64; P=0.000) in all the evaluated samples. Conclusions: The FITC-PNA/PI technique simultaneously evaluates viability and acrosomal status in llama spermatozoa and calcium ionophore could be used as a control of AR.