Improvements in an apparatus designed for electrical ejaculation in the guinea-pig (Cavia porcellus)

Abstract

The procedure here described appears repeatable and non-traumatic method of electroejaculation, which might be of utility in studies such as those performed to determine the effects of both radiation and/or drugs on sperm production in the guinea-pig (Cavia porcellus). Essentially, the electro-ejaculator device consists of four distinct and coupled circuits: a power supply, an oscillator circuit with a driver, a timer and a meter circuit, connected to a 110V, 60Hz source. A guinea-pig analogue output (parallel RC circuit) was associated to the apparatus yielding a fixed current of 28 mA. Two electrodes were utilized in order to transfer the electrical signal to the animal: one anal and one lumbar (placed between vertebras L1-L3). The electric pulse, in a maximum number of five, were given at 10 seconds intervals. During semen collections, that performed weekly, the apparatus worked in a AC current (square wave) with a 4 seconds time adjustment for shocks that were delivered in a frequency of 1000Hz. Electrode jelly was applied to the skin to ensure a perfect electrical contact with lumbar electrode. A total of 591 ejaculations were obtained from 53 animals, during 16 weeks; the semen was collected in 2ml Sorensen phosphate butter containing 2 mg alpha-chymotrypsin.