Spotting symptoms is vital to stop its spread

2 March 2001

Spotting symptoms is vital to stop its spread

Being able to identify foot-

and-mouth accurately over

the coming weeks is a must

for all those handling

livestock. Jeremy Hunt finds

out the facts on this highly

infectious disease

ERR on the side of caution and assume the worst if you notice anything unusual about your stocks health as vigilance is the best weapon to combat further spread of foot-and-mouth disease.

"Checking stock regularly and looking for any unusual signs of ill health is paramount to ensure that the disease is spotted as quickly as possible," advises Herts-based independent vet Tony Andrews.

But many producers and stockworkers have never seen stock with foot-and-mouth, so what are the tell-tale signs?

Speaking to FARMERSWEEKLY, vets explain the symptoms differ in the various livestock species. Dairy cattle infected with foot-and-mouth will often show reduced milk yield; all infected cattle will begin to salivate excessively, start to shiver and appear listless. Foot lesions usually occur on the coronet band or interdigitally. Mouth ulcers are not always evident initially.

Foot-and-mouth infection in pigs can produce symptoms of differing severity. Mouth ulcers and lesions are not always immediately noticeable, although some pigs in the current outbreak have shown severe mouth lesions of up to 6cm (2.5in) develop within hours.

Infected pigs are often lame and prefer to lie rather than stand and squeal when they are encouraged to move, but they may not always have a high temperature.

All vets say that identifying the disease in sheep presents the biggest challenge to producers.

Sudden lameness is often the tell-tale sign that a flock could be harbouring foot-and-mouth victims. Hobbling ewes, which are a common sight in many flocks, should not be ignored even if they are known to be prone to foot problems.

As trough feeding becomes more widespread, during lambing, flockmasters are advised not to assume any increase in lame ewes is due to dietary changes or caused by wet ground conditions at feeders and hay racks.

Infected sheep usually prefer to lie down and may appear hunched-up. As with pigs, infected sheep do not automatically have a high temperature when infected and lesions can be small and difficult to detect.

"Foot-and-mouth can be difficult to spot in sheep, but if your flock is fine one day and suddenly overnight there are say five ewes out of 200 which are lame, alarm bells should be ringing," says Dr Andrews.

Many producers running large numbers of pigs have become concerned about their ability to spot individual pigs showing signs of the disease. But vets says that because of the highly contagious nature of foot-and-mouth, several animals would be likely to contract the virus making identification easier.

"Feed intake of infected pigs is reduced, so producers should be watchful for animals slow to come to the trough or for any that hang back in the pens. There may or may not be lesions and there will not be any scouring. The vet should be contacted if there is any cause for concern," says Dr Andrews.

Young animals are at greater risk, so lambs should be checked as carefully as ewes.

Bury St Edmunds, Suffolk-based vet, Jake Waddilove recommends producers not to re-house stock such as ewes and lambs that have already been turned out.

"Once stock are outside, it is better to leave them where they are and try to achieve effective control measures. Every livestock producer should be defining the perimeter of his farm and ideally ensuring that any grazing stock is unable to contact a neighbours animals over field boundaries"

Milk, saliva, dung and the fluid from blisters can all spread foot-and mouth-disease. It is a virus that is kept alive by cold and darkness and destroyed by disinfectants, sunlight and heat. Dogs, cats, poultry, wild game and vermin can all transmit the disease as passive carriers.


&#8226 Ensure aware of symptoms.

&#8226 Signs differ with species.

&#8226 Young animals also at risk.

Types of virus

THERE are several different types of the foot-and-mouth virus; the current outbreak concerns the O type virus which has one of the shortest incubation periods.

This characteristic is something disease experts hope will work in favour of tracking the diseases spread and lead to control measures being put in place more effectively.

MAFF officials were not prepared to comment on the option of a short-term vaccination programme being introduced as a method of control. But animal health experts disclosed privately that a country-wide vaccination policy would be too costly for producers and would also impact on UK livestock exports.

As one vet told FARMERS WEEKLY: "Far better not to have foot- and-mouth at all than to mask its existence and live with it under a vaccination policy."

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