Organic sheep graze medicinal herbs

By Martin Cassidy
Rural affairs correspondent

While many intensive sheep farms rely on routine drenches to control intestinal worms, at least one organic flock is finding that herbs can replace the chemical treatments.

It's late in the season but a soft Irish autumn means the pastures are still lush and green at the Greenmount organic farm.

The sheep feed on chicory to combat worms

This year's lambs are well grown now and college lecturer Charlotte Moore swings open the gate to allow them into fresh grazing.

But this is no ordinary pasture because as well as the grass and clover mix, a wide strip of chicory has been planted along one side of the field.

Even this late in the season there are distinctive blue flowers dotted through the green, leafy sward of herbs.

And now the lambs are moving straight to the herbs, nibbling the leaves.

Ms Moore explains that instead of being dosed with a worm drench every six weeks or so, the sheep are brought to the chicory field.

The precise science behind it is still being investigated but the researchers believe that tannins in the chicory plant suppress worm eggs in the sheep's intestines.

"There is more to it than that," says Ms Moore who says that a full scale experiment is now under way to better understand the medicinal properties of chicory.

But for now the evidence is that the herb is proving an effective wormer.

For two years now, the Greenmount flock has not had to be drenched and laboratory analysis of the sheep's droppings shows there is no build up of worms in the animals.

Chicory has been planted in the field

Charlotte Moore describes the results as "encouraging" and says the sheep are fond of the chicory.

So much so, that if chicory seeds are included when pasture is being sown out, the sheep tend to graze it out.

Access to the chicory strip is restricted to just a few days at a time and this seems to be enough to purge the worm burden from the sheep's gut.

The Agrifood and Biosciences Institute at Hillsborough is now carrying out a a full scientific investigation.

The results may well have significant benefits for not just organic farms but sheep flocks generally where resistance to chemical wormers is an increasing problem.