Live Export: Trial Shows Dehumidification is Impractical

A trial of dehumidification technology on an empty livestock carrier has shown that it is not effective in reducing temperature and humidity at levels that make it a practical tool for reducing heat stress for animals.

The Australian industry body LiveCorp ran a series of tests to the Middle East. LiveCorp CEO Sam Brown says: “We consider the trial a success, and the data that’s been collected will be invaluable in guiding further research. However, the modelling of what happens when you add sheep into the equation shows you would need technology able to deliver around three times as much dry air to remain effective.”

Sheep generate heat, making it hotter on the deck of a vessel than it is outside. The industry currently uses ventilation systems to blow fresh air through the decks and reduce the impacts of heat, carbon dioxide and ammonia on the livestock.

“While the model shows dehumidification can be more effective than the fans alone at higher temperatures, there’s no way a vessel could carry the number of units that would be required for all decks. To be viable, consideration has to be given to weight, size, and the amount of power being used,” Brown said. “We don’t have an immediate solution.”

The technology trial is part of an on-going response to whistle-blower footage aired on 60 Minutes in April 2018 which showed thousands of sheep suffering severe heat stress; sheep caked in melted feces and urine; injured and sick animals left to die slowly; decomposed bodies left in pens with living sheep and pregnant ewes giving birth and their lambs dying. 

The dehumidification trial was funded through an Australian Government grant of A$2.2 million ($1.5 million).

The professional veterinarian association Vets Against Live Export has previously commented that: “The project ignores the end destination conditions that exported livestock will face when they are unloaded from any potentially “dehumidified” ship. It is a waste of $2.2 million that would have been better spent helping primary producers finding alternative markets for mutton (noting the current high prices at the moment for both lamb and mutton).”