05/07/2021
Researchers are using data from a September voyage from Fremantle to the Middle East which had 40 climate loggers on board, to investigate how sheep respond to varying stocking densities at different temperatures.
It is the latest in a series of trials being carried out under a four year partnership between the LEP RD&E Program and University of New England (UNE), looking at the interaction between stocking density, bedding and ammonia production.
UNE researchers are using climate controlled rooms at The University of Queensland QASP in Gatton, which allow precise control of the temperature and humidity to replicate the ship’s environmental conditions.
Merino sheep sourced from the New England were first acclimatised to the conditions they would have faced in the pre-export quarantine feedlot in Peel, Western Australia, and adapted to eating the pelleted feed used on ships.
In total, 12 pens have been set up with three different stocking densities, and individual identification numbers painted on the side of every sheep. Video cameras above and beside each pen are recording constantly, and the team will spend months after the ‘voyage’ is complete reviewing standing, lying, eating, grooming and other behaviours.
Respiration rates, panting and rumen temperatures are being monitored around the clock so any sheep in distress can be removed (only one, as of day 19 of the 21 day ‘voyage’), food and water intake for each pen is being recorded, and technicians are checking and logging the room’s climate 24/7.
Other equipment – some of it designed and built especially for this project – includes:
rumen boluses in selected sheep, recording internal body temperatures and respiration rates
thermal cameras
infrared cameras and googles to allowing monitoring through the night
accelerometers to record when sheep are standing, lying and moving around
temperature loggers and wet bulb thermometers of the types used on ships, to compare data from the room’s built in sensors
hand-held ammonia monitors, as air turnover is at minimum ASEL levels to help keep temperature and humidity at the right levels to replicate the original voyage data.
This experiment is looking solely at stocking density in relation to climate, so the flooring is designed to ensure there is no pad build up. Other trials over the four years of the project will examine other variables – such as pad, ammonia levels, and the movement of the ship - and gradually build a picture of how each potential stressor affects the physiology and behaviour of the livestock.
Each experiment will be conducted using both sheep and cattle, and trial designs are workshopped in the planning stage with a working group of exporters, department representatives, and staff from LiveCorp and Meat & Livestock Australia.
Several researchers are being accredited as shipboard stock hands, with the aim of conducting trials down the track on ships to validate the findings from the lab in real-life conditions.