9 August 2002

Foot-rot:Catch em quick & cull repeat offenders

By Marianne Curtis

INDIVIDUALLY identifying sheep is an important factor in foot-rot control so repeat offenders can be easily recorded and culled, according to a researcher at Warwick University.

Geert Wassink analysed results from a survey of producers attending Sheep 2000 finding 86% of more than 200 participating producers had seen foot-rot on their farms in the year between November 1999 and October 2000.

"Catch lame sheep as soon as you see them and identify with an individually numbered ear-tag. Record why you suspect they are lame."

Sheep with foot-rot pose a risk to the rest of the flock and should be isolated, recommends Dr Wassink. "Isolate infected sheep. Dont trim their feet, as there is a danger of trimming healthy tissue when feet are swollen which could make lameness worse. Instead, give one long acting antibiotic injection immediately and wait five days."

After five days, trim feet and treat with foot spray, he says. "Keep sheep isolated for a further 14 days. Those which are cured can return to the main flock, but sheep which remain lame should be culled to rid the flock of carriers."

Bought-in sheep can also exacerbate the problem, he warns. "When possible, buy sheep from foot-rot free flocks. Isolate new purchases for at least three weeks and treat sheep with foot-rot during the quarantine period. Avoid mixing these lame sheep with lame sheep from the main flock, as they may be carrying new strains of foot-rot bacteria."

As well as foot-rot, the survey also covered scald. "Foot-rot incidence was similar throughout the year, however, scald peaked in May and June with 20% of lambs infected in many flocks. Producers often perceive scald to be a bigger problem than foot-rot as it sets back lambs."

Scald is best treated using foot sprays or foot-bathing, advises Dr Geert. "Ensure foot-bathing equipment is in good order and try to foot-bath on dry days.

"Stand sheep on hard surfaces for at least one hour after foot-bathing to allow disinfectant to dry and kill bacteria.

"Follow dilution instructions carefully, as too high concentrations of foot-bathing chemicals can damage the skin of feet. Then turn sheep on to a clean field after foot-bathing to avoid re-infection from bacteria on pasture." &#42

FOOT-ROT ADVICE

Present on 86% of farms.

Identify infected sheep.

Cull repeat offenders.