# Performance Evaluation of Fan-Ventilated Swine Trailer with Air Filtration for Maintaining Satisfactory Transport Conditions

## TL;DR

This study shows that a new swine trailer with ventilation and air filtration improves pig welfare and comfort during transport in both cold and warm weather.

## Contribution

The study introduces and evaluates a novel trailer design with mechanical ventilation and air filtration for swine transport.

## Key findings

- The enhanced trailer maintained stable temperatures and improved air quality for pigs during transport.
- Pigs in the enhanced trailer showed reduced stress and no injuries or mortality during transport.
- Carbon dioxide levels and humidity in the trailer were within acceptable ranges, indicating good air quality.

## Abstract

This study addresses the growing concerns that current swine transport trailers expose animals to thermal stress, injury, and handling difficulties, thereby compromising animal welfare and contributing to significant economic losses within the Canadian swine industry. The primary goal of this study was to evaluate the performance of an enhanced swine trailer fitted with mechanical ventilation and air filtration systems, providing an acceptable environment during transport. Road tests with pigs were conducted in both cold (−10 to 10 °C) and warm (10 to 15 °C) weather to assess whether the installed ancillary systems and added trailer features could maintain required temperatures and air quality. Animal behavior, physiological stress indicators, and overall well-being were also monitored during transport. Results demonstrated that the enhanced trailer maintained more stable environmental conditions, reducing exposure to extreme temperatures and improving air quality relative to conventional swine transport trailers. Pigs (weighing 25 to 30 kg) transported in the enhanced trailer exhibited behavioral and physiological indicators of reduced stress and improved comfort. No injuries and transport-related morbidity and mortality were recorded during transport. These findings suggest that the adoption of enhanced trailer design can substantially improve animal welfare during transport while also reducing production losses and enhancing the economic sustainability of swine operations.

In response to new and emerging challenges in animal transport, including more stringent biosecurity and public demand for enhanced animal welfare, an innovative prototype trailer with mechanical ventilation and air filtration systems was developed. The performance of the trailer in maintaining acceptable environmental conditions for the pigs during transport in both cold and warm weather was evaluated through a series of road tests. In these tests, the general welfare of the animals during transport was also assessed. Results showed that temperatures inside the animal compartment during cold ambient conditions were above 10 °C for more than 60 to 90% of the trip despite the frequent occurrence of cold temperatures (below 0 °C) at the inlet. On the other hand, the temperature in the animal compartment ranged from 16 to 19.4 °C most of the time during transport in warm weather. The average moisture levels in the animal compartment ranged from 4.15 to 6.3 g/kg dry air and 5.05 to 78.8 g/kg dry air during cold and warm transport conditions, respectively, which is comparable to the humidity ratios measured in conventional pig transport trailers. Carbon dioxide concentration inside the animal compartment ranged from 912 to 1192 ppm in cold conditions and from 1008 to 1414 ppm in warm weather, indicating good air quality in the trailer during transport. Furthermore, there was no significant change in the levels of blood cortisol and in the rectal and body temperatures of pigs measured at the start and end of each monitoring trip, indicating that the pigs showed reduced or minimal stress during transport. The study demonstrated that the trailer design with a mechanical ventilation system significantly improved the thermal comfort and environmental conditions for pigs, contributing to their welfare during transport.