There are many conditions that can cause lameness in sheep and goats. The information below is a general outline of possible causes. It is recommended to engage a veterinarian to confirm a diagnosis and guide treatment plans. For information on the prevention and treatment of lameness visit the Preventing and Treating Lameness in Sheep or Goats page.
Footrot (including scald)
Footrot is a serious infectious disease that affects sheep, cattle and goats. It occurs throughout Australia but is most prevalent in medium to high rainfall areas. Virulent aggressive strains of footrot infection cause severe footrot lesions and spread rapidly in warmer, moist environmental condition. Other strains of the bacteria causing footrot do not cause serious disease and are regarded as benign strains.
In the face of a footrot outbreak, it is not sufficient to simply footbath sheep until they no longer show the signs. An outbreak of virulent footrot requires a comprehensive on-farm program which treats the lameness and eradicates footrot from the property. If an eradication program is not implemented, then footrot will return each time the seasonal conditions are conducive to the disease developing. If footrot infection is suspected on a property, professional advice should be sought to develop an eradication program that best suits the particular property and management strategies.
Signs
- Often affects more than one foot.
- Lameness.
- In mild cases (known as scald), some reddening between the toes.
- In more severe cases, underrunning (ie separation) of horn from hoof. Starts at the heel, then progresses to sole, toe and eventually outer wall.
- Infected feet often smell.
- Infected feet may become flyblown.
Causes
- The bacteria that cause footrot lesions is called Dichelobacter nodosus.
- Unless there has been a previous footrot outbreak in your stock already, the most likely way of introducing the bacterium to your property is by the introduction of new stock that are infected. The bacterium that causes footrot can live in the feet of a carrier sheep indefinately, even under dry conditions. A paddock which has had no sheep, goats or cattle in it for seven days can be guaranteed free from footrot.
- Control of spread involves footbathing (for long or short term actions).
- Footbathing helps treat existing lesions and reduce the spread of bacteria, improves the health, welfare and production of sheep, enhances the effect of a footrot vaccination program if used and provides precautionary quarantine treatment for introduced sheep.
Eradication
- Eradication programs involve the identification and removal of all infected sheep from a flock when footrot is not spreading.
- All feet on all sheep must be inspected, and infected sheep or those requiring extensive foot trimming should be culled. In some cases salvage treatment with foot paring, footbathing and antibiotic treatment can be used.
- Repeat inspection is made four weeks after the initial inspection and all sheep that do not have four perfectly normal healthy feet at the second inspection should be culled. Regular inspections should continue until two successive totally clean inspections of the flock has been achieved.
- Surveillance and monitoring is continued until the stock have been through a spring spread period without any detection of footrot.
Foot abscess
Signs
- Lameness and obvious acute pain.
- Swelling, usually just above the hoof.
- In more severe cases, a build up of pus can be seen in that area just above the hoof or between the toes.
- Often only one foot is affected and it is more likely to be a front foot.
- Usually foot abscess affects only a small number in a flock.
Causes
- Bacterial infection of a foot that has suffered physical damage or prolonged irritation, such as grazing stubble.
- Wet paddock conditions.
- Overzealous paring.
- Failure to maintain sheep's feet in good condition.
- Heavy sheep are more prone to foot abscess.
Treatment
- Pare or trim
the feet, clean the infected area and apply an anti-bacterial compound. Antibiotic injections and keeping the sheep on a dry surface will assist healing. Applying zinc sulphate and bandaging may help. Many cases take a prolonged period to heal and often the foot is permanently deformed.
Prevention
- Ensure the sheep's feet are kept in good condition by regular inspection and paring. Prevent sheep from getting too heavy. Pre-lamb shearing has helped in some cases.
Foot-and-mouth disease (FMD)
- FMD has not occurred in any state of Australia for 130 years. An outbreak of FMD would be a major threat to the whole of Tasmania's livestock and tourism industries - especially if the first case of any FMD outbreak is not diagnosed very quickly. That is why it is so important that livestock owners do not assume that lameness in any of their animals is simply footrot or one of the other foot problems that occur in Tasmanian sheep and goats from time to time. Any lame sheep or goat should be inspected without delay.
- For more detailed information on FMD see our
FMD web page.
Signs in sheep and goats
- Lameness.
- Blisters on the feet (between the toes and/or immediately above the hoof), around the mouth (especially the dental pad) and, more rarely, around the udder.
- These blisters burst after a few days and become sores hence sores may be seen rather than blisters.
- It is important to understand that the signs of FMD in sheep and goats are usually much less obvious than in cattle or pigs. Typically, only a small percentage of animals in the flock have the signs. And, even then, these signs may be modest.
Causes
- FMD is caused by a highly contagious virus which can be easily introduced by direct contact with an infected animal, or by the virus becoming airborne and spreading from an infected animal up to a few kilometres away.
- The FMD virus can survive for long periods in feed, in wood (ie fences, sheds), in soil, in water, clothing, vehicles, and even on plastic. Virtually any such matter coming onto a property could be a source of FMD. Hence disinfection is an extremely important part of farm biosecurity during an FMD outbreak.
Treatment
- Under the nationally-agreed AUSVETPLAN, animals with FMD or that are deemed to be at risk of FMD (in most cases, animals on properties near an FMD outbreak) would be slaughtered. Strict quarantine and movement restrictions would apply to all other susceptible livestock during any FMD outbreak.
Prevention
- Keep the FMD virus out of Australia through strict
quarantine controls at our airports and seaports.
- Ensure everyone who comes into the country is aware of and abides by the import bans or restrictions on various foods and other potential carriers of the FMD virus.
- Vigorously enforce the ban on feeding prohibited pig feed (previously known as 'swill') to pigs.
Note
- Because Australia has not had FMD for over 130 years, there is a risk we could become complacent. Of all the exotic animal diseases, FMD is the most potentially serious - mainly because of the speed with which it can spread.
- Our first line of defence against FMD is our quarantine barrier. Our second line of defence relies on farmers and all other people who work with livestock to know what FMD looks like and to report any suspect animals immediately. That is why it is so important not to ignore or delay a close inspection of any lame sheep or goat.
If you suspect FMD please call 1800 675 888, the Emergency Animal Disease Hotline.
Ovine interdigital dermatitis (OID)
Signs
- OID looks like scald, which is a mild form of footrot.
- Reddening between the toes. Sometimes fluid weeps into this area.While OID looks like the early stages of footrot, there is no underrunning of the horn.
- Often affects more than one foot.
Causes
- Warm wet weather, especially when the pasture is lush or the paddocks muddy.
Treatment
- Remove the sheep from the lush pasture or muddy paddock. Overnight housing on the grating in the shearing shed or on a dry, hard floor is often sufficient. If possible, put the sheep into a drier pasture or less muddy paddock afterwards.
Prevention
- As the organism that causes OID is ever present, the disease can occur whenever the weather and paddock conditions are conducive to the bacterium establishing infection. There is little that can be done to prevent OID. In warm wet weather pasture sheep on the drier parts of the property.
Shelly hoof
Signs
- In severe cases, lameness.
- The horn starts to separate from the hoof, usually along the outer wall. A cavity forms between the horn and the hoof and this fills with soil and dung. When paddock conditions are wet, this can result in inflammation and the establishment of a bacterial infection.
- Sometimes the separation of horn from hoof starts at the toe and the cavity forms at the front of the foot.
- The prime cause of Shelly Hoof is poor maintenance of the feet, it is likely that other sheep in a mob would have been similarly neglected and may therefore also have the condition. Usually, however, only a small number of sheep in a mob are lame. The lameness often affects only one foot and more often a front foot than a back foot.
Causes
- Failure to maintain the sheep's feet in good condition.
- There is some evidence that Shelly Hoof may be, in part at least, hereditary.
- Merinos are more susceptible than British or European breeds, especially in higher rainfall areas. Sheep with black hooves are generally less susceptible.
Treatment
- Unless infection is present,
paring the feet and cleaning the dung and soil out of the cavity is all that is needed.
- If infection is present or suspected, the sheep should be
footbathed as well.
- If paddock conditions are wet, try and keep the sheep on drier ground after paring.
- If rocky ground is available or if the sheep can be grazed on a gravel farm track for a day or two after paring, the action of walking on very hard ground will tend to empty any remaining material from the cavities in the feet.
Prevention
- If shelly hoof is a problem regular foot inspection and paring should be instigated. Paring should always be minimal, as radical paring can predispose the animal to other foot infections and hoof damage. The overall goal is to have the sheep's feet in good condition especially before the wet conditions of winter and early spring.
- When paddock conditions are wet, running sheep on dry, rocky ground or on gravel farm tracks for short periods will help maintain hoof shape and health.
Scabby mouth
Signs
- The signs of Scabby Mouth can appear around the mouth and/or on the legs and feet.
- The infection is more common around the mouth than on the legs or feet.
- Young sheep are more susceptible (mainly because, once animals have recovered from the disease, they are immune to it thereafter).
- The first signs of Scabby Mouth are small blisters discharging pus. These then dry and create a scab which may be yellowish brown at first and then become dark.
- Where Scabby Mouth affects the legs, it is usually on the lower part. If the infection spreads down to between the claws of the hoof, the animal will be severely lame.
- Scabby Mouth is not a fatal disease and will rarely cause major secondary problems.
- The disease can affect the udder and teats of a lactating ewe. As a result, the ewe may prevent the lamb from feeding until the pain goes away. This would be a major setback for the lamb.
In some circumstances, Scabby Mouth and Foot-and-Mouth Disease (FMD) can present very similar signs, so check your sheep against the signs of FMD and if you have any doubt that it is Scabby Mouth, contact your local vet or the Emergency Animal Disease hotline (1800 675 888 all hours) immediately.
Causes
- The Scabby Mouth is caused by a pox virus. The virus can survive in the soil for years, however, it cannot enter the sheep unless the sheep has some kind of wound or abrasion. Puncture wounds from grass seeds, thistles, blackberry etc can be sufficient to allow entry of the Scabby Mouth virus, as can shearing cuts or any wounds from lamb marking, ear tagging etc. Sheep grazing a stubble can get minor abrasions around the mouth that would expose them to the virus as well.
Treatment
- If left untreated, the lesions generally heal in around three weeks. As yarding the sheep in order to treat them may actually make the disease worse, no treatment is usually the best option. You should ensure affected sheep have soft, palatable feed, water and plenty of shade during this natural recovery phase. Depending on the time of year and seasonal conditions, you may need to keep a close watch for flystrike on the lesions.
- You should not attempt to remove the scabs, as this will delay the sheep's recovery.
- Antibiotics are not necessary, unless there is some secondary infection.
Prevention
- A sheep that has recovered from Scabby Mouth is immune from the disease for several years. Note, however, that this immunity is NOT passed from the immune ewe to her lamb via the colostrum.
- A preventative vaccine is available. In most cases, vaccination is only a viable option if the sheep are intended for the live sheep trade. Apart from this, vaccination for Scabby Mouth is not usually part of normal sheep management. The effect of the vaccine is to introduce the disease into the sheep in a controlled on-farm environment so that the sheep are then immune for the export market.
- The vaccine is a live virus and is therefore not recommended for any property where the Scabby Mouth virus is not already known to be present.
- The risk of Scabby Mouth is reduced if you remove blackberries, thistles and other potentially wounding plants (and, of course, any wire, nails etc that may be lying in the pasture) from the areas to be grazed. In particular, avoid running young sheep in paddocks where there are these risks.
Zoonosis
- Scabby Mouth is transmissible to humans, where the condition is known as Orf. People most at risk are shearers and people using the Scabby Mouth vaccine in their flock.
Strawberry footrot
Signs
- Presents as scabs and hair loss on the lower leg. If the scabs are removed, the bleeding sores resemble strawberries - hence the name Strawberry Footrot.
- Lameness with potential severe swelling which may extend up the leg.
Causes
- Strawberry footrot is not a footrot at all but a form of dermatitis caused by an infection with Dermatophilus congolensis (dermo bacteria) and often occurs in combination with Scabby Mouth virus. Dermo bacteria are normal skin bacteria on a sheep and only cause a problem under specific conditions, such as damp spring pastures.
Treatment
- Treatment should involve a vet to confirm diagnosis.
- Lesions should be shorn and kept dry until healed, and long-acting antibiotics may be prescribed.
- Footbathing the whole flock, starting with sheep that are not showing signs of infection, can aid in healing, reduce infection severity and decrease transmission to other sheep in the flock.
Prevention
White muscle disease
Arthritis
Signs
- More common in lambs, but can affect all ages.
- Lameness, the affected animal usually "carries" the infected leg.
- In many cases, the affected leg has a swollen knee joint.
- In "post dipping lameness", the lower leg is inflamed.
Causes
- Infection arising from lamb marking under dirty conditions or lambing in unclean paddocks. Infection usually enters via the umbilical cord or wounds from lamb marking or mulesing. Infection can also enter through unbroken skin.
- "Post dipping lameness" is caused by the build up of an infecting organism in sheep dips. The organism enters the sheep via abrasions or grass seed sites in the skin.
Treatment
- For bacterial arthritis, the only treatment is a course of massive doses of antibiotic and may only be viable with valuable animals. Treatment is unlikely to be effective in chronic cases due to irreversible joint damage.
- In cases of "post dipping lameness", the affected sheep usually recover without treatment.
- If you are relying on natural recovery from viral polyarthritis or "post dipping lameness", make sure the animals have easy access to food, water and shelter while they are lame.
Prevention
- Good hygiene at lamb marking time is essential. Avoid using your regular sheep yards, as they will be contaminated.
- Using rubber rings to mark lambs will avoid open wounds and thereby reduce the risk of infection substantially.
- Have your ewes lamb in clean paddocks, well away from regular sheep camps.
- If using a plunge or shower dip, include a bacteriostatic agent in the mix. Replenish dips and sprays frequently and, where possible, disinfect the equipment between replenishings.
Copper deficiency
Signs
- Severe ill thrift
- Diarrhoea
- Steely wool
- Loss of pigmentation in black sheep
- Lameness through spontaneous fractures
Causes
- Insufficient absorption of copper in the sheep's digestive system. This normally means that copper is deficient in the soil, but not necessarily so. It is possible for soil tests to show adequate copper levels, but excessive levels of other minerals (in particular molybdenum, iron or sulphur) may inhibit the uptake of copper by ruminant animals.
Treatment
- Supplementary copper can be provided as stock licks, drenches, additives to fertiliser, copper "bullets" and injections.
Prevention
- It is important not to treat animals that are not copper deficient, as too much copper is toxic and can kill. So, only use preventative copper treatments if deficiency has been diagnosed on your property.
- Laboratory testing of liver or blood samples is the best way to diagnose copper deficiency. Deficiency is most common from late winter to late spring, so this is the best time to test.
Physical injuries
Causes
- Rough handling of sheep.
- Sheep can sometimes get one claw "caught" in the grating in a shearing shed. If the sheep is then moved without the claw being released, injury can occur.
- Dog attack. Where the attack is by a pack of dogs, there is usually a lot of blood that is easily seen from a distance. However, some domestic dogs, including poorly trained sheep dogs, may simply "nip" the back legs of a sheep and this can cause lameness.
- Loose fencing wire can become tangled around the sheep's leg. If the sheep is woolly, the wire may not always be easily seen from a distance.
- Anything sharp in the pasture (ie loose barbed wire, sharp stone etc) can puncture the sole of the foot, which may then become infected.
Treatment
Prevention
- Ensure that your sheep handling facilities are safe. In particular, repair any damaged grating in the shearing shed. Check the gaps in the grating every now and then and fix any areas where the gap is sufficient to "catch" a sheep's foot.
- Don't leave loose wire (especially barbed wire) lying in the pasture. Also, remove any other risks, such as old scarifier points, nails etc if you see them in the pasture.
- If you have a dog attack on your sheep or goats, always report it to the local council and do all you reasonably can to have the offending dogs caught. Once dogs have attacked sheep on your property, the same dogs are likely to keep returning.
- British breeds are less susceptible to dog attacks than Merinos, because they are generally more "assertive" when confronted by a dog. However, when dogs form a pack, any resistance by the sheep is likely to be ineffective.
- If your neighbour's dog wanders on to your property, however harmlessly, you should insist your neighbour keeps better control of the dog. Even mild-mannered pet dogs can join packs and attack sheep.
- There is never any excuse for handling livestock roughly. If a shearer, livestock carrier or anybody else shows signs of rough handling, you should intervene before any injury to the animal occurs.
Some people seem unable to work with animals without losing their temper and/or being cruel. The livestock industry can well do without these people. If you are unfortunate enough to come across someone like this, you should ensure they have nothing to do with your animals. If you see an act of cruelty on an animal, you should always report it to the RSPCA, NRE Tas or your local police.