Electrostatic particle ionisation (EPI)

Improving air quality in pig buildings is important for both pig and staff health. One way of improving air quality could be to use electrostatic particle ionisation (EPI).

EPI creates a static charge to particles in the atmosphere through a high-voltage, low-amperage current, connected to a corona bar. This causes particles to fall onto the corona bar, removing them from the atmosphere, which means pigs and staff do not breathe them in.

To research whether this is an effective way of improving air quality, we commissioned Harper Adams University to investigate.

The initial trial (2016) demonstrated that pigs kept under the EPI equipment were significantly less likely to have enzootic pneumonia-like lesions.

The study was extended to include Pig Health Scheme data from more batches kept in normal (control) conditions and in test conditions using EPI.

The addition of a random effect to account for batch was the only alteration to the original model.

For more information, watch the video summary below.

• Pigs kept in the EPI environment grew on average 13 g/day faster than the pigs in the control environment
• In the second trial, the incidence of pleurisy halved in slaughter pigs reared in the EPI environment
• The probability of EPI reducing EP-like lesions at slaughter weakened from the first trial to the second, from around 4.5 times less likely to have an EP-like lesion in the original two batches to around 2.5 times less likely in the following six batches. This indicates a trend rather than statistical significance in research terms
• The extension of the work eliminated the concerns around a batch effect masking any benefit/drawback of the equipment and demonstrated a benefit in respiratory health