30 August 1996

EFFORT FOR FOOT-ROT FREEDOM

WORTH

Eradicating foot-rot from a sheep flock takes time and effort but the experiences of one Oxon producer suggest it is well worthwhile.

John Burns reports

AS WELL as directly addressing the welfare aspects of lame sheep, a foot-rot-free flock is more productive and less labour demanding.

This is the experience of Stephen Hart, whose own flock has been completely clear of this disease for 16 years.

"For instance we never pare sheeps feet except the odd lame one," he says. "We do still get a few lame sheep even though we have no foot-rot. Their feet may suffer from thorns, cuts or other damage, leading to localised infection. But this never turns to foot-rot. Last year as an experiment I pared just the right feet of some rams in the spring, but did nothing to the left feet. By the autumn, you could not tell the difference between right and left feet. So in the absence of foot-rot routine paring of feet seems to be pointless."

Sustained effort

Mr Hart emphasises that eradicating foot-rot needs determined and sustained effort for many months, and then constant vigilance to prevent its reintroduction. Foot-rot-free status has been achieved three times on farms under his management. Twice at his Hammonds Farm, Check-endon, in Oxfordshire – the second time because bought-in replacements were introduced just too soon before they were 100% clear of foot-rot – and once at another farm.

Mr Hart says the principles behind foot-rot eradication are simple and it need not be expensive, except in time and effort. Foot-rot is caused by two bacteria acting together. "Eliminate one and there will be no foot-rot. The one to go for is the one which cannot survive away from sheep for more than a few days. Kill those bacteria on the sheeps feet and preferably move the sheep to pasture which has not seen any sheep for at least seven to 10 days."

Regular foot-bathing

The bacteria can remain inactive in feet for at least six months. So regular foot-bathing and treatment is needed for at least that length of time, and feet must be carefully pared with a sharp knife to expose infected tissues to the treatment.

Mr Hart used formalin, but it is now being suggested that zinc sulphate is just as effective while being safer and nicer to work with.

He made up large foot-baths which would take up to 15 ewes at a time so they could be left standing in the formalin for at least 10 minutes to give it time to penetrate. There was also a concreted area after the foot-bath, on which treated sheep could stand until their feet dried, giving time for the formalin to kill the bacteria.

Weaning is the best time to start a foot-rot eradication programme, he believes. Lambs can be dealt with separately and there is maximum time before lambing for infection to show and be dealt with.

It was Mr Harts present shepherd, Steve Atkinson, who eradicated foot-rot from the flock 16 years ago and he makes no bones about the determination and effort needed to achieve it.

"Its like any success with livestock, it depends on attention to detail," says Mr Atkinson. "Its no good skimping or rushing the paring and foot-bathing. I was only doing 75 a day at the start. We had them standing in water to soften their feet and clean them up before they went in the crate for examination and paring.We aimed to uncover every bit of infection and found a sharp knife was best. The ewes were then divided into three groups: Clear, infected, and borderline. After foot-bathing and standing on concrete to dry they went to clean paddocks. Every night I swept up the foot parings and then sloshed formalin around the pens to kill any bacteria still there."

He foot-bathed each group once or twice a week and re-examined the borderline and dirty groups at intervals of about a fortnight, paring again where necessary. Any considered free of infection were transferred to the clear group. The foot-bathing continued until lambing time 1980, at fortnightly intervals in the later stages.

To provide enough paddocks to allow them to be rested for six or seven days so that they could be considered clear of foot-rot bacteria, some larger fields had to be temporarily sub-divided.

A few ewes with really bad feet which did not respond to treatment were culled.

To keep a flock clear of foot-rot once it has been eradicated, potential carriers of the disease must not be allowed onto the farm. Boundary fences must be secure to keep out other peoples strays and prevent your sheep straying out onto foot-rot-infected pastures.

And remembering that foot-rot bacteria could be picked up in a lorry which has not been thoroughly cleaned and disinfected, or from roadside verges used by other flocks which are not foot-rot-free, or from sheep at market. No sheep should be brought onto the farm from a market. Not even your own lambs which failed to make the price you wanted, says Mr Hart.

It also means isolating bought-in rams or female replacements and clearing them of foot-rot before mixing them with the main flock. The work involved each autumn and winter to achieve that was one of the reasons why Mr Hart closed his flock and developed his own prolific breed, the Hartline. He also breeds most of his own Texel rams. His involvement with breeding and selection has convinced him of the importance of discarding any ram with unsound feet. "The shape of feet and the way the white line breaks down and packs with mud appears to be highly inherited. So we never use a ram with feet walls that break away."

Many benefits

Mr Hart is absolutely convinced of the many benefits of foot-rot-free flocks. "We have not had a flock of ewes in for routine foot-paring or foot-bathing since 1980. That is quite a bonus for a flock of over a thousand ewes." But he is reluctant to recommend foot-rot eradication to anyone buying in flock replacements every year, because of the risk of re-introducing foot-rot and other diseases.

Mr Atkinson says foot-rot could certainly be eradicated from each new intake of sheep, provided time and facilities were available to do the work. But the time and effort involved should not be underestimated and it would be an annual requirement. &#42


&#8226 More productive.

&#8226 Less labour demanding.

&#8226 Improved welfare.


FOOT-ROTERADICATION


FOOT-ROT-FREE FLOCKS


&#8226 Weaning best time to start eradication programme.

&#8226 Aim to kill bacteria than cant survive off sheep for more than a few days.

&#8226 Move sheep to clean pasture

&#8226 Regular foot-bathing with formalin or zinc sulphate.

&#8226 Pare feet with sharp knife to expose infected tissues.

&#8226 Keep potential carriers off farm.

Oxon producer Stephen Harts sheep flock at his Hammonds Farm has been completely free of foot-rot for 16 years.

Shepherd Steve Atkinson makes no bones about the effort and determination needed to achieve a flock thats foot-rot free. Do not underestimate time needed.