Administration of cloprostenol and oxytocin before electroejaculation in goat bucks reduces the needed amount of electrical stimulation without affecting seminal quality.

Electroejaculation (EE) is a widely used semen collection technique; but, it is stressful and painful for the animals. Considering these concerns, it may be important to develop practices to decrease the negative implications of EE on animals. Oxytocin and prostaglandin-F2alpha (PGF2α) stimulate the contractions of the muscles of the male genital tract. Therefore, the aim of this study was to analyze the effectiveness of the administration of oxytocin and/or a PGF2α analogue (cloprostenol) to bucks in relation to their stress response and sperm parameters before semen collection by EE was performed. Semen was collected with EE from 12 Gabon bucks in a 2 × 2 factorial arrangement (factors: with or without oxytocin, with or without cloprostenol). Each treatment was applied to different animals every 3 to 6 days, allowing all the animals to receive all the four treatments. The treatments applied to bucks before EE were as follows: 1) control (ConT), bucks received no hormonal treatment; 2) oxytocin (OxyT), bucks received 10 IU of oxytocin intramuscularly (IM) 30 s before beginning the EE; 3) PGF2α (PgT), bucks received 250 µg of cloprostenol IM 5 min before beginning the EE; and 4) oxytocin plus PGF2α (OxPgT), animals received treatment with both OxT and PgT. The number of electrical pulses, time length needed to achieve ejaculation, number of vocalizations, creatine kinase (CK) concentration and sperm parameters in goat bucks were recorded. The administration of cloprostenol and oxytocin before EE shortened the procedure and decreased the number of pulses and the pulse/voltage applied (P = 0.02 for all). This treatment also tended to decrease the number of vocalizations (P = 0.067). There were no treatment effects in the initial values; neither were there increases in heart rate and rectal temperature, or CK concentration. Seminal variables were not affected by the treatments. In conclusion, it would be important to consider the combined application of cloprostenol and oxytocin before EE, as it can shorten the process, reducing the electrical stimulus with positive effects on animal welfare and without affecting seminal quality in goat bucks.