5-134
Benign: No clinical signs. Other animals in herd affected
Intermediate: mild to moderate signs, +/- fever (normal temp is 103-104°F), foot odor may be present, mild
lameness
Virulent Form: Systemic signs of fever/anorexia, lameness, fetid odor, swelling of soft tissue, sloughing of the
foot, inflammation of deep tissues, secondary infections.
Using Advanced Tools: Lab: Bacterial cultures may identify organism.
Assessment:
Differential Diagnosis: Other bacterial or fungal infections, trauma, bluetongue (inflammation of mouth
and nose; sometimes accompanied by lameness), ulcerative dermatosis
Plan:
Treatment: Treat infected animals. Observe other animals in flock for signs of infection.
Trim (debride) all exposed and necrotic tissues. This is critical for proper treatment of tissues.
Apply local disinfectant (5% formalin, 10% ZnSO4, or 5% CuSO4).
Administer antibiotics (infected animals): IM Penicillin 50-70,000 u/kg and dihydrostreptomycin at
22,500-32,000 u/lb.
Move animal to dry pasture or ground.
Cull (remove from herd) or destroy recurrent carriers to protect rest of animals.
Vet Medicine: Equine Lameness
MAJ Joseph Williamson, VC, USAIntroduction: Lameness is a general term associated with pain in one or more legs due to injury, illness
or conformational abnormalities. Lameness resulting from injury and infection will be discussed here.
Conformational injuries, fractures and the majority of the soft tissue malfunctions require extensive treatment
and/or diagnostic tests that are beyond the capabilities of the medic in the field. Systematically conduct a
physical examination. Begin by examining the hoof and work your way up to the shoulder or pelvis. Look for
lesions, injuries, swelling and bounding pulses. Use hoof testers (special pliers used to squeeze soft tissue)
to apply light pressure to all parts of the hoof, to include the wall, frog and sole. Check for sores, abscesses
and painful conditions not readily seen on exam.
Subjective: Symptoms
Owner complains of animal being lame (not bearing weight on the affected limb or carrying it in an unnatural
or awkward position). Subtle lameness may only be detected at the trot or on hard-packed surfaces. Owner
may report foul odor from hoof; obvious injury, swelling or lesions; animal constantly shifting weight or
standing with hind limbs under its body to take weight off the front limbs.
Objective: Signs
Using Basic Tools: Fetid odor from hoof, bounding digital pulses, swelling of joints or leg, hot hoof walls,
tenderness elicited with hoof testers (or substitute), abnormal or stilted gait, bowed or swollen tendon and
tendon sheaths.
Assessment:
Differential Diagnosis: Thrush - Fetid odor with moist exudative dermatitis of the underside of the hoof.
Laminitis, conformational abnormalities, bowed tendons, traumatic injury, fractures
Plan:
Treatment
Trim the affected tissue
Treat thrush with antiseptics, such as iodine or copper sulfate
Treat laminitis with pain relievers: Phenylbutazone 4.4-8.8 mg/kg/day divided bid or tid slowly IV or po,