Final answer:
Severe acute lameness in horses can be caused by hoof abscesses, bowed tendons, and neurologic diseases.
Step-by-step explanation:
Severe acute lameness in horses can be caused by various factors, but one of the most common causes is a hoof abscess. A hoof abscess is a localized infection within the hoof that can cause sudden and severe lameness. It is typically associated with pain, swelling, and heat in the affected area.
Bowed tendon, also known as a tendon strain or a tendon tear, can also cause severe acute lameness in horses. This injury occurs when the tendon fibers in the horse's leg become overstretched or torn, leading to pain, swelling, and lameness.
Neurologic diseases, such as equine protozoal myeloencephalitis (EPM) or equine herpesvirus (EHV-1), can also result in severe lameness in horses. These conditions affect the nervous system and can cause weakness, incoordination, and lameness.