Common Causes of Poor Performance in the Horse

By Liana Wiegel, DVM, Pilchuck Veterinary Hospital

The ability of the horse to perform at any level is dependent on coordinated movements and complicated relationships among multiple different body systems. When one or more of these systems deteriorates, the horse is no longer able to perform at its best. 

The most easily recognized source of poor performance is lameness. Any athlete with any degree of soreness will not be able to run as fast or turn as sharply, and the same is true for your horse. Some lameness conditions can be improved upon with joint injections, while others, such as ligament damage, require a long period of rest and rehab. For progressive conditions, such as hock arthritis, radiographs taken over the course of the horse’s life can be very helpful for determining the horse’s future progression as an athlete. Lameness in one area can also create soreness in other areas, such as compensating with the opposite limb or back. There are also diseases of the muscles (e.g., HYPP [hyperkalemic periodic paralysis] and PSSM [polysaccharide storage myopathy]) that can appear as weakness, stiffness or muscle trembling. Therefore, addressing the horse’s lameness as quickly as possible, or having a veterinarian evaluate your horse even when you do not suspect a problem, can help prevent further damage or injury and get the horse back to peak performance.

Another potential cause of poor performance is a respiratory problem, such as recurrent airway disease (heaves), inflammatory airway disease or exercise-induced pulmonary hemorrhage. All of these can be very subtle clinically and may only manifest themselves as poor performance. Symptoms such as coughing, nasal discharge, changes in effort of breathing, or taking longer for the respiratory rate to come back down after work should all be taken seriously.  

A less frequently thought of but all too common cause of poor performance is a dental issue. Is your horse not turning well to the right because he has a sharp point stabbing him each time you pull on the bit? Even bitless bridles can be irritating because the cheek pieces can be pushing his cheeks into his sharp points with movement of the hackamore. A very common dental conformational problem is an overbite of the cheek teeth, with or without overbite of the incisors (parrot mouth). These can create sharp points that cause the horse significant discomfort without any noticeable weight loss or trouble eating.  

Lameness, respiratory problems and dental problems are just a few of a multitude of different issues that can attribute to poor performance. Decline in athletic ability in the horse can be very difficult to diagnose because some signs can be very subtle. If only the horse could just point and tell us where the problem is! A thorough history, detailed examination and diagnostic procedures are necessary for any successful course of treatment to return the horse to peak performance.  

Pilchuck Veterinary Hospital offers equine ambulatory care, referral hospital services and 24/7 emergency. Call 360.568.3111 to schedule a consultation with one of our equine practitioners.

Photo: Dr. Wiegel with veterinary technician Pam Poole and HD, Pam’s horse.

Article added 6.6.15