Modification of a standard dump trailer into a mobile carbon dioxide depopulation unit for swine

Abstract

Carbon dioxide (CO2) is an American Veterinary Medical Association approved swine euthanasia method. A limitation for the use of CO2 during depopulation events, such as a foreign animal disease diagnosis, is the ability to apply the method to finisher and adult pigs. The common euthanasia methods in finishing and adult swine require individual animal handling and restraint, increasing human safety risk in large-scale depopulation events. This project validates the modification of a standard dump trailer into a mobile CO2 depopulation unit. The success of the method was verified with subdermal implants for monitoring heart rate, activity, and body temperature.

Reliability of water‐based medium‐expansion foam as a depopulation method for nursery pigs and cull sows

“…As a function of the opaque nature of WBF, pigs were obscured from visual observation during the depopulation process; therefore, a threshold was needed to establish ‘cessation of movement’, as no visible confirmation could be performed to validate any activity output from the bio‐logger. The bio‐loggers used in this study had not previously been validated for activity in swine, but validation of the external acceleration as a good activity measurement have been conducted in other species such as salmon and sheep (Fuchs et al., 2019 ; Zrini & Gamperl, 2021 ) and used successfully in a recent swine depopulation study using CO 2 (Pepin et al., 2022 ). Ideally, a true activity baseline should have been collected over the previous days to the field trials for increased sensitivity for activity threshold development, but this approach was not logistically achievable at the time of the study.…”

“…Gas-based methods may also be impacted by limited gas supplies and gas delivery systems depending on season and geographical location. Insufficient data has been generated under field conditions to establish firm guidelines for emergency situations, but several mobile prototypes for depopulating larger cohorts of pigs using inhalants such as CO 2 have been proposed (Kinsey et al, 2016;Meyer & Morrow, 2005;Pepin et al, 2022;Rice et al, 2014;Stikeleather et al, 2013).…”

“…Gas‐based methods may also be impacted by limited gas supplies and gas delivery systems depending on season and geographical location. Insufficient data has been generated under field conditions to establish firm guidelines for emergency situations, but several mobile prototypes for depopulating larger cohorts of pigs using inhalants such as CO 2 have been proposed (Kinsey et al., 2016 ; Meyer & Morrow, 2005 ; Pepin et al., 2022 ; Rice et al., 2014 ; Stikeleather et al., 2013 ). Lastly, ventilation shutdown with the addition of elevated temperature and humidity has been listed in the AVMA guidelines under ‘permitted in constrained circumstances’, but little peer‐reviewed information on the method is available in the literature (Baysinger et al., 2021 ).…”

Evaluation of a Water-Based Medium-Expansion Foam Depopulation Method in Suckling and Finisher Pigs

“…Finisher and suckling-sized swine used in the present trials could be placed in larger containers, trailers or other compartments with solid sides and flooring amenable to holding mediumexpansion water-based foam. In our previous work, we used a modified rendering trailer to depopulate groups of sows [17], as did Kinsey et al (2016) and Pepin et al (2022), when investigating carbon dioxide euthanasia [12,13]. The use of mobile containers, such as trailers, may also facilitate movement and disposal of the animals post depopulation, which will likely depend on causative pathogen and movement restrictions that may be in place.…”

“…Currently, the use of inhalants, such as carbon dioxide (CO 2 ) and nitrogen (N 2 ), may be a viable option for swine mass depopulation, as multiple animals, regardless of age, size, and weight, can be terminated simultaneously. However, there is concern regarding the aversiveness of gases when inhaled [6][7][8] and few depopulation studies using CO 2 for swine have been undertaken in field conditions [9][10][11][12][13]. In addition, the use of CO 2 requires the availability of large amounts of the gas, associated gas delivery equipment, including vaporizers, and airtight containers to apply and hold the gas and pigs.…”