Two research experiments at Iowa State University were designed to assess the effectiveness of a single application of the CASH Dispatch Kit (Accles & Shelvoke) as a method of euthanasia of pigs at different ages in a laboratory and a commercial farm setting.

Forty-two pigs were tested in the laboratory trial and 209 in the farm trial. Enrollment was based on weight, sex and skull shape. Pigs were enrolled from seven weight classes: 4.4 to 6.6 lb., 16.5 to 22 lb., 33 to 44 lb., 66 to 88 lb., 220 to 264 lb. and 440 to 550 lb.

Four styles of captive bolt gun heads were used: a non-penetrating head, a short penetrating bolt, a medium penetrating bolt and an extended penetrating bolt.

Death was determined according to cessation of cardiac and respiratory functions.

All pigs in the five lightest weight classes were effectively euthanized. Of 72 pigs in the heaviest weight categories, 11 required a secondary method of euthanasia.

Researchers observed that there were associations between the stockperson and a number of variables in the need for a second shot, but reasons need to be further studied for clarification.

Observations suggest that landmarks on the pig head were usually correctly identified, but ensuring that the pistol was flush against the head at a correct angle was likely to affect efficacy.

Restraint of the head through snaring appeared to be important for efficacy and safety, rather than restraint in a chute or stall.

In conclusion, the CASH Dispatch captive bolt device is effective as a single-step euthanasia method for pigs under 440 lb. For heavier weights, further refinements in the equipment design and application are needed to ensure reliable performance.

The project was funded by the National Pork Board.

Researchers: Jennifer Woods and Suzanne Millman, Iowa State University. For more information, contact Millman by phone (515) 294-2817 or e-mail smillman@iastate.edu.