October 8, 2013
Victorian sheep producers should be preparing their spring and summer grass seed management strategies to help minimise the negative impact of grass seeds on their flocks.
Department of Environment and Primary Industries (DEPI) District Veterinary Officer Jim Walsh said strategies to reduce the impact of grass seed contamination of sheep and their wool should include pasture management, breed selection, animal management and fleece preparation.
“In Victoria, grass seeds usually affect sheep during late summer and autumn,” Dr Walsh said.
Common problem grass varieties in northern Victoria include barley grass (Hordeum), and Stipa and Erodium commonly known as corkscrew.
“Eyes can be infected and seen to be inflamed or closed; the affected sheep will become listless or unwilling to move freely since they can’t see properly,” he said.
“Some may show skin irritation and can be seen trying to scratch or rub because the seeds are penetrating their skin.”
Dr Walsh said it was important for producers to develop an awareness of the impacts of grass seed to the wool and meat industry. Trimming and quality downgrades at the abattoirs means lower prices to the producer and seed in wool means lower returns.
“By monitoring your flocks for seed infestation plus seeking feedback from meat processors and wool traders, producers will be able to measure the size of the impact from grass seeds,” he said.
“It’s important not to underestimate the negative effect that grass seed contamination can have on your flock’s productivity.”
Once producers have identified problem grasses, a management plan should be put in action.
Dr Walsh said different grazing strategies could have both short and long term results. Increased stock density rates for short-term heavy stocking could help reduce problem grass infestations and feedlotting can avoid contamination.
“Livestock management strategies include strategic timing of lambing and shearing,” he said.
“Agronomic management can be applied using pasture manipulation, fodder crops and fodder conservation and timing of marketing and turn off can assist reducing infestations.”