Ocelot and oncilla spermatozoa can bind hen egg perivitelline membranes.

We evaluated the capacity of ocelot and oncilla spermatozoa to bind to the perivitelline membranes (PVMs) of hen eggs in a sperm binding assay (S-PVM). In addition, a device that improves the standardization of the assay was developed. The number of sperm bound to the PVM in fresh (T1) and frozen-thawed (T2) semen from both species was compared to the sperm quality observed in routine tests. The PVM was stretched on a circular silicone device to create a standardized area for analysis. In both treatments and for both species, the spermatozoa were able to bind to the PVM, indicating that PVM may be used for a sperm binding assay in ocelot and oncilla. The S-PVM assay did not differ in fresh and frozen-thawed ocelot sperm (p>0.05). However, fewer oncilla sperm (p<0.05) were bound to the PVM in T2, indicating that the proposed test may be able to detect injuries that compromise sperm binding abilities. The device maintained the PVM stretched during the processing and defined the evaluation area.