Sheep that were fed hemp pellets showed production gains, indicating potential for a high yielding, multi-purpose, summer feed option for livestock, according to a study in the state of Western Australia.
The pilot study, “Opening the gates to hemp grazed livestock in Australia,” was carried out by the state’s Department of Primary Industries and Regional Development (DPIRD).
“The most profound outcome was the increase in minor volatile fatty acids, suggesting an improvement in energy availability and a change in the composition of the gut microbial population, which may account for the improved digestibility,” said Bronwyn Blake, who led the research team.
Results showed the digestibility of dry and organic matter were higher for both hemp diets compared with a control, though it is not clear why, the researchers reported.
Fifteen Merino wethers in New South Wales were fed hemp pellets made from the Morpeth Late hemp variety grown in Western Australia. The diets were manufactured into 8-millimeter pellets by a Western Australia stock feeds company that processes hemp under license. The sheep were fed three diets and five replicates per feeding, with measurements taken for digestibility, performance and developmental traits over 56 days.
Addressing THC issue
The study showed THC was apparent in all measured tissues. While the levels were extremely low, they would not meet Australian regulatory requirements. But Blake said the results suggest it will be possible to develop management practices for feeding hemp biomass to sheep, goats and cattle that can meet animal feed rules. No THC residue may be present in feed intended for livestock in Australia other than in approved research trials.
The results of the research will lead to a second-phase study which will explore the nutritional value and how to meet market regulations for hemp as a possible forage crop. That further research will also investigate the pathways to market for livestock-fed hemp, including clearance rates for THC.
The DPIRD pilot was funded by AgriFutures Australia, in collaboration with the ChemCentre and Charles Sturt University.