Date Full Report Received07/18/2008
Date Abstract Report Received07/18/2008
Funded ByNational Pork Board
Swine producers must inevitably deal with on-farm euthanasia of low viability and compromised piglets. Compromised piglets are of low economic value and may be underweight, weak, malformed, emaciated or have other conditions that reduce their welfare and long-term survival. At the present time, carbon dioxide, electrocution, anesthetic overdose and blunt trauma are all considered humane methods for euthanasia of farrowing pigs on-farm (American Veterinary Medical Association, 2001). Because of human safety, cost and convenience, blunt trauma is one of the most common methods used, although it may not be aesthetically or emotionally acceptable to those staff members that have the responsibility of performing euthanasia. A method that is effective, easy to use and more emotionally acceptable to farrowing house staff would be a valuable alternative. Recently, a non-penetrating captive bolt device was developed using a pneumatic nailing gun with the addition of a hard plastic ball, powered by a portable air compressor (Zephyr). Preliminary trials on dead piglets and a small sample (n=4) of low viability neonatal piglets indicated that when this device was applied perpendicularly to the head of a piglet at an air pressure of 120 PSI, it resulted in severe trauma to the skull and immediate unconsciousness followed by death in the live piglets. The objective of this study was to evaluate the effectiveness of this non-penetrating captive bolt device in comparison to traditional blunt trauma for on-farm euthanasia of low viability neonatal pigs when performed by different stock people. Eleven stock people from six commercial and one research farm were supplied with a Zephyr gun and air compressor and trained how to operate the device. Each stockperson performed euthanasia on some piglets using the Zephyr (n=99) and some using Blunt Trauma (n=76). Experimenters recorded signs of consciousness (eye reflex, breathing, jaw tone), and duration of reflex movements (leg paddling) and heart beat (time of death). Degree of head trauma was scored during post-mortem examination. All piglets were immediately rendered unconscious by both methods, but piglets euthanized by the Zephyr had significantly longer durations of leg movement (~ 2 minutes) and took longer to die (~6 ½ minutes) than piglets euthanized by the traditional method stopped moving at around 1 minute and died within 3 minutes. There was some variation among stock people for some of the measures. Around 13% of piglets began to regain signs of sensibility after the Zephyr compared to none with Blunt Trauma. These results indicate that manual blunt trauma to the head is a rapid and humane method for on-farm euthanasia of low viability piglets. Further modification to training, technique and the apparatus are required before the Zephyr can be recommended as an equally humane alternative for piglet euthanasia.