Evaluation of trailer thermal environment during commercial swine transport

Transport is a critical factor affecting swine welfare in modern U.S. commercial pork production. Broad temperature ranges encountered during transport can challenge pig welfare and have been shown to increase the number of dead or down pigs following transport. Despite the general understanding of the relation between challenging transport conditions and pig welfare, little quantitative data exist which document conditions within transport trailers. To better characterize the thermal environments experienced by trailered pigs during hot, mild, and cold weather, The National Pork Board commissioned this observational study to evaluate the thermal environment during commercial pig transport when the trailer environment was managed according to a set of industry guidelines. The overall goal of this observational study was to identify weather conditions and micro-climates within the trailer that created thermal challenges for the pigs. In this study, 84 temperature sensors were placed across trailer cross-sections in six evenly distributed zones within the transport trailer to measure air temperature experienced by the pigs. Six relative humidity and temperature probes were installed on the central ceiling of each zone to measure a representative moist-air state point for each compartment. Eighteen to twenty-four floor temperature sensors were placed onto the trailer floor prior to each monitoring trip to measure trailer floor/bedding temperature. Transport thermal environment data from forty-three monitoring trips were collected from May 2012 to February 2013, with trailer management conducted by a commercial hauler following the National Pork Checkoff Transport Quality Assurance (TQA) guidelines. The thermal environment profile within the trailer was used to evaluate the thermal conditions to which pigs were exposed over a broad range of outside conditions [-14 to 38°C (7 to 100°F)] encountered over the four seasons of this study. Results indicate that for outside temperature below -7 (20°F) and above 32°C (90°F) , pigs experienced extreme thermal conditions inside at least some portions of the trailer when managed according to current TQA guidelines. The ventilation patterns inside the trailer did not follow the same trend for all monitoring trips, revealing a potential to manipulate ventilation patterns with trailer management strategies. This approach for improving the thermal extremes needs further exploration. The effectiveness of fans and misting for cooling the pigs was critically impacted by the location and coverage areas of the spray nozzles and fans. When outside temperature ranged from 10 to 20°C (50-68°F), trailer environment was within acceptable thermal limits without misting the pigs. During cold weather, frozen floor conditions were observed, with floor temperature as cold as -20°C (-4°F) recorded in some areas of the trailer. No evidence was found to suggest that bedding depth had a measurable effect on the thermal comfort of the pigs, and its presence might increase the severity and likelihood for the pigs to be loaded onto freezing or frozen bedding in extreme cold weather. Our data revealed no critical problems with boarding level recommendations based on current TQA guidelines, but indicated that industry guidelines could be modified to offer greater flexibility for drivers for boarding and bedding.

Name thesis:degree_name

M.S.

Level thesis:degree_level

Thesis

Discipline thesis:degree_discipline

Agricultural & Biological Engr

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2014

Author dc:creator

• Xiong, Yijie

Contributors dc:contributor

• Green, Angela R.
• Gates, Richard S.

• swine transport
• market-weight pigs
• trailer thermal environment
• industry recommendation
• alternative practices

Statement dc:rights

• Copyright 2013 Yijie Xiong

Language dc:language

en

Handle dc:identifier

http://hdl.handle.net/2142/46789

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/46789