CONICET | Buscador de Institutos y Recursos Humanos

The development of safe and consistent semen collection protocols should be ensured to understandbasic sperm parameters of a species. Electroejaculation has been hypothesized and tested to be a safemethod to evaluate male reproductive potential in wild animals. However, little is known about semencollection protocols in lizards. Adjusting stimulation to species and body mass is important for efficientsemen collection as well as for animal welfare. Tropidurus spinulosus is a good model to adapt electrostimulation;it is a medium-sized lizard species, males have semen during a long period and operativesex ratio is male-biased. We aimed to provide a thorough and safe method for collecting semen samplesfrom this animal model by means of electrostimulation and characterize basic sperm parameters. Maturemales of T. spinulosus were captured and their testicular volume was evaluated via portable ultrasoundscanning. The lizards were electrostimulated by performing standardized series of stimuli. Semen wasobtained successfully in 94% of the males. Samples were contamination-free. Mean sperm number ofejaculates was 2.1 ± 1.8 106 spermatozoids. The percentage of motile spermatozoa was 78% and spermdynamic parameters were: VSL 37.26 ± 7.72 m/s and VCL 84.26 ± 16.27 m/s. We observed high variabilityin testicular volume among males; however, almost all the individuals had sperm. Electrostimulationusing protocols adjusted to a medium-sized lizard was an effective semen collection method thatallowed us to obtain semen samples with high motility (percentage of motile spermatozoa and spermvelocity).