The un-anesthetized Chinchilla were placed in a box that covered the cephalic half of body while the rest laid on a metallic grid support. After cleaning the genital area the prepuce was retracted and the penis was introduced into a 2-ml Eppendorf plastic tube. The rectal probe was lubricated with glycerin and the bronze bipolar electrode (length ≈ 40 mm, diameter ≈ 4.2 mm) was inserted into the rectum to a depth of 20 to 30 mm and help by the technician.
The alternative current (220 V, sinusoidal wave, 50 cycles/sec) was applied for 5 of every 10 sc. The current was controlled by a rheostat and was calculated from an oscilloscope reading of the voltage drop across a resisted placed in the circuit. A series of 1 to 6 pulses was normally given at the 6 to 6.8 V setting.
Immediately after electro-stimulation a white viscous plug was obtained, which was discarded. The remain portion of the ejaculate was collected and diluted with 150 µl. Tyrode’s buffer medium without BSA (pH 7.4 – 280 mOsm/Kg) in order to avoid coagulation. After measuring the volume, functional parameters of spermatozoa were determinate within 5-10 min by subjective evaluation in fresh (immediately after electro-ejaculation) and in frozen-thawed semen.