We often think conformation is genetic, but did you know environmental factors can also play a role?
Many people look for a horse that has the perfect conformation for their sport. Most Friesians wouldn’t do well at the Kentucky Derby, for example, and very few Standardbred racehorses would make good hunter/jumpers.
In theory, a horse with excellent conformation should experience fewer injuries, require less recovery time, and be easier to train than one with a less desirable shape. The problem lies in what makes up a horse’s conformation, and that involves a combination of genetics and environment. The expression of genetics is plastic (changeable). It is a fundamental mechanism of development, homeostasis and adaptation regulated by the central nervous system. The evolutionary goal of a horse’s DNA is to be a horse, and changes to the environment affect the DNA’s expression. Conformation is just the current expression of the body’s DNA as it relates to its environment.
Posture and Conformation
Great conformation results in a biomechanical balance that allows the horse to have an appropriate, stable, predictable, confident and easy interaction with gravity. The goal is for the nervous system, muscles and bones to interact with gravity as efficiently as possible. There are four centers of balance in the horse – the feet, head, back and abdominal organ systems. These centers send signals to the brain, shaping the sensory and motor cortexes and implementing how the horse interacts with gravity.
Posture and conformation are often confused. Posture defines the body’s relation to itself. It holds the body against gravity. Posture enables critical body functions to occur, because if the horse is able to maintain a neutral stance, his body is able to prioritize the essential functions of maintenance, like eating, sleeping, and healing from injury. An inability to maintain a stable compensatory posture that balances the body, while resting an injury, will delay healing and make the animal more susceptible to re-injury. An inappropriate compensatory stance (or abnormal posture) results from internal or external alterations to reflexive postural control mechanisms. These include feedback from the four balance centers mentioned earlier.
Challenges that Affect Posture
No hoof, no horse Domestic horses rely on humans to maintain their feet. Things as common as long toes, heels that are under run, causing them to land in front of the bony column, and wearing shoes, all inherently change neural signaling from ground contact to the brain. Changes in the structure of the head-neck relationship, dental occlusion and foot balance distort critical nerve signals to the postural centers in the brain and spinal cord. The distorted signals create compensatory postures that chronically impair balance and locomotion.
The input from your horse’s feet tells him which muscles to contract and which to relax in order to stand. When a horse has good posture, he is utilizing very few muscles and very little energy. This passive stance allows him to be ready to move in any direction at a moment’s notice. In the wild, this is important because it allows the horse to keep away from danger. If a horse is receiving faulty input, he will stand in positions that require active muscle contraction to maintain. The recruitment of mobilizing muscles to support standing results in muscle soreness and joint instability. This abnormal posture requires the horse to relax the mobilizing muscles before being able to move. The stabilizing muscles’ primary function is to maintain the relationship between various parts of the body; moving the body parts is secondary.
The jaw, head and neck Historically, the horse eats while standing, ready to flee if necessary. Eating while standing with the head lowered to the earth is a normal process and allows for the relaxation of flight muscles, making them ready to act when needed. Eating with the head up, above ground level or at shoulder height, fatigues the extensor muscles in the neck, especially if the horse is in a discipline that requires little neck flexion below the elbow. This reduces the normal pattern of flexion and extension that allows cellular waste products to be excreted and efficiently mobilized out of the system. This change in environment can actually lead to the development of metabolic issues.
Horses that eat with their heads up all the time alter their chewing mechanics and will develop problems with their teeth. The horse’s lower jaw moves forward when the head is lowered, so the lower molars grind evenly. The teeth are designed to deal with hard grasses. We now provide our horses with much softer grasses and feeds, causing sharp enamel points and protuberant teeth to develop. An asymmetrical posture and head carriage cause a misaligned mandible, uneven wear, and eruption of teeth, creating malocclusions. Chronic subluxations result.
Is it his Conformation, or his Posture?
When limbs are not perpendicular to the ground at the cannon bone, or when your horse is unwilling to stand and bear weight on all four limbs simultaneously, he is compensating. This results in a difference in muscle tone. Chronic asymmetrical weight bearing can be shown by looking at disparate hoof size. Sickle hocks may be the result of weak muscles on the outside of the legs; hunter’s bump is due to under run heels; and dropped fetlocks arise from weak muscles in the back. All these weakened muscles occur because of subluxations in the spine. These horses can’t stand, let alone compete, well.
The body is constantly in a state of healing and repair. Every day, the body of an adult horse produces 300 billion new cells. This takes energy. During asymmetrical stance, the horse uses more energy against gravity than he does during normal stance. This entire process is monitored, controlled and coordinated by the central nervous system.
Chiropractic care helps your horse maintain wellness by optimizing the performance of his central nervous system, reducing fatigue and aiding in the best possible performance. Posture can be altered to bring out the best in your horse, regardless of his genetics!
William Ormston, DVM, and Amy Hayek, DVM, have a combined experience of 40 years, allowing them to teach movement to other veterinarians. Dr. Ormston owns Jubilee Animal Health in Celina, Texas and Dr. Hayek owns East Coast Equine in Summerville, South Carolina. In addition to practicing, both doctors are well known lecturers and travel extensively all over the US and internationally. They can be reached via HYHH.TV or http://AnimalChiropracticEducation.com