Other Causes of Lameness in Cattle Flashcards
What is the aetiology of sole haemorrhage/bruising?
Traumatic damage to the corium between the pedal bone and the sole results in bleeding which is incorporated into the sole horn as it is produced. This haemorrhage or “bruising” becomes visible as the sole grows out or when the foot is trimmed. NB The sole horn itself cannot bruise once it has been produced (it is avascular).
Sole haemorrhage and discoloration can occur as a result of movement of the pedal bone (as discussed in the lecture) and inadequate cushioning provided by the digital cushion. That is bruising has a similar aetiology to sole ulceration and should probably be considered simply as an earlier and milder manifestation of the same disease.
What are the clinical signs and presentation of sole haemorrhage/bruising?
Animals will often present with low-grade lameness or tenderness (short strides where the hind feet do not track up to the forefeet), sometimes on more than one foot. When examined the sole contains areas of bruising. On some occasions the bruising will not become obvious until the sole horn has grown out (or been trimmed back) to become weight bearing which may take a number of weeks
How do we diagnose sole haemorrhage/bruising?
Diagnosis is usually apparent as soon as the foot is examined. In cases where areas of sole bruising have not yet reached the weight-bearing surface the only sign may be pain when the area is percussed or “pinched” with hoof testers or by excluding other causes of lameness.
How do we treat sole haemorrhage/bruising?
Treatment depends on the degree of lameness and the severity of lesions. Overgrown feet should be therapeutically trimmed to restore correct weight bearing. Recent UoN research has demonstrated that animals benefit from the application of a block to the unaffected claw and a course of NSAIDs even at this early stage of disease. Alternatively, animals often respond well if kept on straw beds for a week or two.
How can we prevent sole haemorrhage/bruising?
Ensure optimal underfoot conditions and comfortable housing to maximise lying times. Institute routine foot trimming of all animals.
What is the aetiology of foreign body penetrations?
Penetration of the foot in areas other than the white line (usually the sole) with foreign bodies from the environment is not an uncommon finding. Objects commonly found imbedded in the sole are nails, sharp stones, black thorns, pieces of metal & glass and molar teeth which have been cast into the environment. Foreign bodies carry infection through the sole to the corium which then establish infection and abscesses in a similar fashion to WLD.
What are the clinical signs and presentations of foreign body penetrations?
Similar to WLD, although lameness is often peracute in onset and severe if the foreign body is still in the sole
How do you diagnose foreign body penetrations
Diagnosis is straight forward if the foreign body is still present. If not black tracks in the sole leading to sub-sole abscesses are diagnostic.
How do you treat foreign body penetrations?
As for WLD. Ensure that the amount of sole removed is sufficient to prevent reimpaction of the affected area with debris from the environment.
What is the prognosis of foreign body penetrations?
Good as for WLD. Occasionally foreign bodies will penetrate into the deep structures of the foot establishing deep digital sepsis. In these cases the prognosis in much worse.
How do we prevent foreign body penetrations??
Ensure that the environment is kept free of potential foreign bodies.
What is the aetiology, clinical signs and presentation of heel horn erosion (slurry heel)?
The result of standing in wet corrosive slurry (a combination of faeces, urine and occasionally silage effluent) during the winter housing period leads to the soft horn of the heel becomes eroded leading to the formation of pits and fissures in the heel. If severe or left untreated the heel eventually disappears completely.
How do you diagnose and what are the differentials of heel horn erosion (slurry heel)?
Presenting clinical signs are diagnostic and cannot be confused with any other condition.
What is the treatment of heel horn erosion (slurry heel)?
Regular formalin foot bathing through the winter will harden the feet and limit the effects of heel erosion. Gently trim away loose and fissured horn to remove pocket but spare healthy heel as excessive trimming this will exacerbate the problem. Corrective trimming attempts to increase the angle of the front wall to the ground to reduce the pressure on the sole ulcer site.
What is the prognosis of heel horn erosion (slurry heel)?
Good if treated before the disease has completely destroyed the heel. If this has been allowed to happen the foot rotates backwards. This causes the front wall of the hoof to meet the ground at a shallower angle leading to overgrowth of the hoof at the toe. At the same time the pressure exerted by the caudal palmer edge of the pedal bone increased which can lead to pinching of the corium the development of sole haemorrhage and eventually sole ulcers.
How can we prevent heel horn erosion (slurry heel)?
Improving underfoot conditions during the winter period will decrease the severity of the condition although a certain amount of heel erosion is almost inevitable in housed cattle. Routine bathing in formalin footbaths will often limit the severity of disease.
What is the aetiology of vertical fissures (sand cracks)?
The periople is responsible for producing a thin waxy layer that prevents the horn of the wall from drying out. If it or the underlying wall producing corium becomes damaged vertical cracks can appear in the wall of the hoof that appear to extend as the wall grows. Common causes of damage are digital dermatitis lesions on the front wall of the foot and trauma. Alternately the condition can occur in very hot dry sandy conditions during the summer months.
What are the clinical signs and presentation of vertical fissures (sand cracks)?
Often asymptomatic, however if the underlying laminae are involved or the crack becomes infected severe lameness can ensue.
How can you diagnose, and what are the differentials for vertical fissures (sand cracks)?
Presenting clinical signs are diagnostic and cannot be confused with any other condition.
How can you treat vertical fissures (sand cracks)?
The crack should be opened up and any underlying abscess exposed and allowed to drain. However on occasions if the crack is opened and there is movement between the two wall sections granulation tissue can develop and protrude through. In these cases the granulation tissue should be resected and a block applied to the sound claw to limit sheering forces.
What is the prognosis for vertical fissures (sand cracks)?
Generally good although some can be quite difficult to treat and require multiple trims before the wall returns to normal. If the periople has been permanently damaged leading to continued production of defective wall the long term prognosis is poor.
What is the aetiology of horizontal fissurres (hardship lines)?
Complete, circumferential horizontal fissures will occur if the production of wall horn is interrupted as it is being produced at the coronary band. Any severe toxic condition e.g. mastitis, metritis, or acute acidosis can results in a temporary but complete absence of horn production. When horn production restarts there will be a complete circumferential fissure often round all 8 claws
What are the clinical signs and presentation of horizontal fissurres (hardship lines)?
Often asymptomatic unless the fissure and the underlying laminae either become infected or the pinching forces result in the production of a granuloma. Many show clinical signs when the fissure has grown down the wall to the point that “thimbles” of wall and sole are formed on all claws. At this point movement of the thimble relative to the rest of the wall results in lameness, infection and granulomas.
How can you diagnose horizontal fissurres (hardship lines), what are the differentials?
Presenting clinical signs are diagnostic and cannot be confused with any other condition.
How can you treat horizontal fissurres (hardship lines)?
If infection has become established the crack should be opened up and any underlying abscess exposed and allowed to drain. Any granulation tissue should be resected. It is often difficult to block the other claw as very often all claws are affected.
What is the prognosis for horizontal fissurres (hardship lines)?
Prognosis varies depending on the severity of the disease. Sometimes thimbles grow out and are eventually shed asymptomatically, on other occasions if all claws are seriously affected it may be necessary to cull the affected animal.
On many occasions the disruption in horn production is not complete, instead a thinning of the wall occurs. As these thinner areas grow down the wall they become apparent as a series of ridges or “hardship lines”. As the wall grows at approximately 5mm per month is it possible to calculate how long ago the insult causing the thinning occurred.
What is the aetiology for a fracture of the distal phalanx?
Fracture of the distal phalanx is an uncommon occurrence but causes rapid onset acute lameness without any other obvious clinical signs. Typical claws affected are the medial claw of front feet following trauma during “bulling” (slipping off cows whilst mounting) or hind feet after slipping of the steps of abreast parlours. Herd “outbreaks” have been associated with fluoride poisoning.
