#08-167

Complete

Category

Date Full Report Received

06/06/2011

Date Abstract Report Received

06/06/2011

Investigation

Institution:
Primary Investigator:
In 2007, the National Pork Board organized a conference of equipment manufacturers, producers, veterinarians and safety experts to identify the goals and challenges for developing a euthanasia system specifically designed for commercial pork production facilities. These discussions led British specialist manufacturer Accles & Shelvoke (A&S), and its North American distributor, Bunzl Processor Division, to embark upon developing a system specifically designed for the euthanasia of swine in commercial operations.
The CASH Euthanizer unit is a heavy duty cartridge propelled captive bolt device with interchangeable muzzle assemblies. The unit provides a non-penetrating captive bolt muzzle for piglets, and a variety of penetrating bolt assemblies for pigs ranging from large nursery to adult swine. In addition, the kit includes all necessary equipment for basic cleaning and maintenance of the unit.
This project was conducted to;
1) To evaluate the anatomical features that determine the effectiveness of captive bolt technology for humane euthanasia of pigs throughout their production life;
2) Determine the traumatic brain injury due to direct damage of the primary regions of the brain of pigs throughout there lifespan from application of the Cash Euthanizer system.
For phase one of the project, the static force required to penetrate the skull plate and sinus cavity was determined for pig heads representing two different skull shapes, three genetic backgrounds, and seven different weight classes.
A Universal Testing Machine was utilized to determine the static force required for penetration of the skull. For the non-penetrating head, the force of penetration was measured when the muzzle face penetrated the skull. For the penetrating bolt, the force of penetration was measured when the bolt penetrated the skull and when the bolt penetrated the sinus cavity. The information gathered on each head included weight, bolt type (non-penetrating head or penetrating bolt), recorded pressure at skull penetration and recorded pressure at sinus penetration

As expected, static force required to penetrate the skull/sinus plate increases significantly as the pig matures, ranging from 0.074 to 7.254 kg/mm2. This provides the basic information necessary to design a captive bolt system for on-farm euthanasia for the US swine industry. However, to fully evaluate a specific captive bolt system (i.e manufacturer/model) a high-speed penetration test should be conducted utilizing skulls of the target species/size with representative speeds and bolt mass.

For Phase two, the level of brain damage inflicted by the Cash Euthanizer captive bolt gun when applied in recommended locations (National Pork Boards On-Farm Euthanasia of Swine-Options for the Producer) was determined by application of the device to cadavers, representing 7 weight classes and both sexes.

Four different muzzles were utilized with the Cash Euthanizer – a non-penetrating head, a short penetrating bolt, a standard length bolt and an extended length bolt. Four different power charges were utilized with the coordinating bolt and weight class. The bolt type and color of the charge were pre-designated based on the manufacturer’s recommendations.
The degree of damage to the skull and depth of penetration was documented utilizing dorsal and lateral radiographs. Skulls were dissected to determine the location of penetration and the primary regions of the brain were scored for traumatic brain injury and presence of hemorrhaging.
Dissection of the brains showed that when utilized in a penetrating bolt configuration the placement of the Cash Euthanizer needs to be higher on the forehead of the animal than with traditional penetrating captive bolts. This higher positioning will achieve maximum overall TBI and result in greater impact to regions of the brain necessary to ensure cessation of heart and respiratory function.
The preliminary results demonstrate that captive bolt technology is sufficient to induce significant brain trauma in regions necessary to cause cessation of heart and respiratory function. This support the use of the Cash Euthanizer as an effective single step method for the euthanasia of pigs from 2 kg’s up to 200 kgs and recent improvements to the Cash Euthanizer System (addition of a more powerful cartridge) by the manufacturer should ensure a humane euthanasia for even the most mature of swine.