Herbs, legumes can cut wormers

Adding a mixture of herbs and legumes into grazing swards can help improve sheep performance and reduce the need to use wormers.

Scientists at University College Dublin (UCD) found that compared to perennial rye grass grazing, adding herbs to multi-species swards could reduce days to slaughter by more than 10 days and slash the need to use anthelmintics to tackle worms.

UCD scientist Cornelia Grace said four ‘farmlets’, each stocked with 30 twin-rearing ewes, were established.

The farmlets contained either perennial rye grass swards, perennial rye grass with water clover swards, a six species sward (two grasses, legumes and herbs), or

“Sward type also had a significant effect on days to slaughter”

a nine species sward (three grasses, legumes and herbs).

Lambs were weaned at 14 weeks and drafted for slaughter at 45kg, during which time they were weighed every two weeks and faecal egg counts were measured.

Lambs were treated with anthelmintics once the group parasite burden reached a set threshold, and the scientists measured the days between each treatment.

“We found that adding herbs to multi-species swards increased weaning weights, with lambs on rye-grass swards weaning at 30.6kg, and those on six species swards weaning at 32.6kg,” said Ms Grace.

“The sward type also had a significant effect on days to slaughter, with lambs reared on perennial rye grass registering 175 days, compared to 162 and 164 days for the six and nine species swards.”

She said the number of worm treatments was also lower on herb-rich multi-species swards. Viewing meat and dairy as the enemy of sustainable food production isn’t as clear-cut as critics of livestock farming might suggest, according to a leading government food advisor.

Sir Charles Godfray, Professor of population biology at the University of Oxford, said there were significant health and environmental benefits in people in developed countries lowering their consumption of meat and dairy products.

But he warned that simply encouraging people globally to adopt vegetarian or vegan lifestyles would not be the panacea many people expect.

Speaking at the British Society of Animal Science conference in Dublin, Sir Charles said the world would not be able to support a population of 10billion people by eating meat at the levels seen in Europe and North America today.

Aside from the environmental impact in terms of greenhouse gas emissions from livestock, the human health issues linked to eating red and processed meats would make such a diet unsustainable, he said.

“Research has shown that eating red and processed meat in particular has negative effects on diets,” added Sir Charles.

However introducing policies - such as carbon taxes on food - to drive down meat consumption would have significant consequences for people living in poorer countries. “There are countries where diets are deficient in calories, so consuming animal products may be desirable,” he said.

“If you plot the number of deaths you’d avoid through carbon taxes geographically you’d get fewer deaths in the rich world, but more deaths in subsaharan Africa and Asia.”

BALANCE: Population biology expert Sir Charles Godfray said in countries where diets are low in calories eating animal products was desirable