Abstract: Animal welfare concerns have been expressed regarding the use of Electro-Ejaculation (EE) as a semen collection technique. Furthermore, there is little information on the stress responses of hair sheep, particularly when effects due to physical manipulation and electrical stimulation are disaggregated during the EE process. Therefore in the present experiment, changes in concentration of serum cortisol in serial blood samples, Heart (HR) and Respiratory Rates (RR) rates were used to quantify stress response to EE in hair sheep males. Eighteen intact F1 Dorper/St. Croix rams aged 12-13 months were randomly assigned to one of three groups: a control group where, no stimulus was applied, compared to rams that a rectal probe was inserted without EE (T1) and males that were electro-ejaculated (T2). Blood samples were collected by venipuncture at 0 (immediately before inserting the rectal probe) 20, 40, 70 and 100 min after the onset of the experiment. At these same intervals, RR was measured, while HR was recorded continuously. Higher (p<0.05) HR was found in T2 in comparison with T1 and controls. The highest rate (218 beats min-1) was observed in T2, 3 min after electrical stimulation was applied, returning to baseline rhythm 45 min after the start of recording. A significant (p<0.05) increase in serum cortisol was detected 20 min after stimulation in T2 when compared with controls and T1. No difference (p>0.05) was found in RR among or within groups. It was concluded that during EE, electricity application induces major changes in HR and cortisol concentration in hair rams, while manipulation, including probe insertion does not contribute significantly to this effect.
A. Orihuela, V. Aguirre, C. Hernandez, I. Flores-Perez and R. Vazquez, 2009. Breaking down the Effect of Electro-Ejaculation on the Serum Cortisol Response, Heart and Respiratory Rates in Hair Sheep (Ovis aries). Journal of Animal and Veterinary Advances, 8: 1968-1972.