Measuring Horse Personality


Last December, I lost Lago, my part-lease horse, to colic. Part of working through this loss was identifying what I liked about this goofy, personable, and sometimes aloof Quarter Horse/Thoroughbred gelding. In May I found Robin, a Thoroughbred/Percheron cross. Robin is interested in people, a little fearful of new things, and enthusiastic about work. Two different horses: two distinct personalities. Thinking about the differences between Lago and Robin, I started to wonder if there is a scientific basis to my intuitive ideas about their personalities. Here is what I found out:

Personality can be defined as an animal’s basic stance toward environmental stimuli that is expressed by behavior patterns and remains relatively stable across time and situations. To measure this, scientists use a combination of qualitative and quantitative methods to reach a conclusion, or test a hypothesis about how a horse behaves and reacts to the world.

For example, the behavior coding method uses trained observers to record behavior of one animal at a time under controlled circumstances. In this study, researchers observed and recorded 13 behaviors (e.g. “aggressive” “alarmed” “fearful” “curious” “friendly” etc.) when horses were exposed to unknown humans in two controlled tests. First, the observers stood outside the stall, observed the horse for 30 seconds and rated the horses to establish a basic score. Then, they rated the horses on the same behaviors when approached outside the stall from a short distance, and inside the stall with touching. Results were consistent across observers and horses; the authors concluded that the test successfully measured personality.

In the trait rating method, observers rate specific, commonly understood traits. This study examined the occurrence of specific breed traits to see if anecdotal knowledge about breed temperament was supported by testing. 1223 horses representing 8 different breeds were assessed by experienced horse people and rated according to 25 traits. Horses were rated on a scale that indicates levels of agreement about a trait (e.g. Strongly disagree | Disagree | Neither agree nor disagree | Agree | Strongly agree). In this study, anxiousness and excitability showed the highest variation between breeds.

Thoroughbreds, Arabs, Welsh cobs were ranked at the top of this list with Irish Draught and Highland ponies at the low end of the scale. Sociability and inquisitiveness showed low variability between breeds, with the Arab and Thoroughbred ranking highest, the Irish Draught and American Quarter Horse ranking lowest. These results align with anecdotal evidence of breed temperaments.

Personality studies are not perfect. There is no one model for describing personality, and there are many methods for measuring it. A horse’s reactions to different stimuli may be different on different days, and human observations can be subjective. Also, horses can become habituated to even the most upsetting noises and situations.

Despite the difficulty of measuring and characterizing equine personality, these studies are useful because they can inform suitability of an individual horse for a job or discipline. This can only be good for both horses and people.

When the Horse Throws Up in Front of the Pharmacy

PharmacyHorse copyMy friend Karin is a dressage rider from Germany, so she was the perfect person to explain the odd German expression: “Ich habe schon Pferde vor der Apotheke kotzen gesehen.” Roughly translated this means “I’ve seen horses puke in front of the pharmacy.”

According to Karin, this phrase is used to express something that is completely unlikely (horse anatomy prevents them from vomiting). For example, “I’m going to clean the house every day” might be met with: “Yes, and I’ve seen horses puke in front of the pharmacy.” – something similar to “Yes, and I’ve seen pigs fly.”

It is true that horses cannot vomit, but why “in front of the pharmacy?”

A horse vomiting in front of the pharmacy is extremely unlikely because 1) Horses don’t vomit and 2) The pharmacy contains all of the possible remedies for vomiting!

Could Platelet Rich Plasma (PRP) be a Treatment for Laminitis?

With knowledge about the molecular mechanisms of chronic laminitis (founder), the biology of PRP (Platelet Rich Plasma), and evidence that PRP helps to heal tendons, ligaments, and wounds, researchers at the Universidad de Caldas in Manizales Columbia describe why they think that PRP (platelet-rich plasma) might be a useful therapy for laminitis.

In their paper, Could Platelet-Rich Plasma be a Clinical Treatment for Horse with Laminitis? the researchers describe five horses that showed new hoof growth and improved hoof horn quality after a course of PRP injections. These horses, which had chronic laminitis after episodes of tying up, colic and traumatic hoof damage, all showed visible improvement after treatment with PRP.

With these encouraging results and a detailed examination of the molecular picture in laminitis, the authors examine the possible ways that the PRP could help tamp down the various cell mediators that contribute to the inflammatory response in chronic laminitis.

Chronic Laminitis

The authors observe that the chronic laminitis is similar to other types of inflammatory responses. The trouble starts when some metabolic disturbance – colic, grain overfeeding, Cushing’s disease, “tying up” (rhabdomyolysis), triggers a series of events that result in inflammation of the sensitive structures (lamellae) that lie between the pedal bone and the inner wall of the hoof. As the disease process progresses, the connection between the coffin bone and the hoof wall deteriorates, leaving the horse with weakened suspensory apparatus of the distal phalanx (SADP); the structures that buffer the daily pounding of the foot on the ground.

Laminitis terms
Laminitis Terms


Inflammation’s Effects

Chronic inflammation has several stages that involve mediators (cytokines, proteins, and enzymes) that act on cells in tendons, ligaments, and bone. In chronic inflammation, an initial inflammatory response kicks off a secondary one that releases matrix metalloproteinases (MMPs), enzymes that break down components of collagen. Also present in inflammation are peptides that control blood vessel constriction, molecules that contribute to neuropathic pain, and other mediators that increase levels of cytokines that act on important structures like collagen, and the molecules that absorb and maintain water in the tissue.

Possibly, according to the authors, the molecular pathways in chronic inflammation could be the same events that cause deterioration and ultimately, separation of the lamellae and hoof wall in laminitis.

 Why could PRP Help?

PRP (platelet rich plasma) is a formulation of blood platelets and plasma (usually from the patient). It is prepared with a centrifuge that separates the components of the blood. An anticoagulant is added so that the liquid does not clot. Platelets produce growth factors and proteins that are known to participate in essential biologic activities including collagen deposition, bone formation, and blood vessel formation.

Growth Factors and Cytokines

Seven growth factors produced by platelets have an effect on some of the molecular actors in chronic inflammation.  PRP is reported to have helped heal equine tendons and ligaments and is currently used in human sports medicine as an aid healing after tendon and ligament injuries. Knowing their general biological actions, and citing the current literature, the authors discuss the potential actions of these on the mechanisms of laminitis.

After describing encouraging results with five horses treated with PRP, the authors have considered why the growth factors released by platelets might help stop the inflammatory cycle that leads to chronic laminitis. “However,” they write, “additional basic and clinical research is necessary to determine the exact role of PRP as treatment of horses with chronic laminitis.” The next step, according to the authors, is more research to examine the specific actions of PRP on inflammation mediators in equine lamellae – specifically, the cell mediators that might be affected by PRP grown factors, and the genes that control them.


  1. Dhurat, Rachita, and MS Sukesh. “Principles and Methods of Preparation of Platelet-Rich Plasma: A Review and Author’s Perspective.” Journal of Cutaneous and Aesthetic Surgery 7, no. 4 (2014): 189–97.
  2. “Laminitis.pdf.” Accessed April 26, 2018.
  3. Libby, Peter. “Inflammatory Mechanisms: The Molecular Basis of Inflammation and Disease.” Nutrition Reviews 65, no. 12 Pt 2 (December 2007): S140-146.
  4. Pollitt, Christopher C. “The Anatomy and Physiology of the Suspensory Apparatus of the Distal Phalanx.” Veterinary Clinics of North America: Equine Practice 26, no. 1 (April 2010): 29–49.
  5. “PRP Information.pdf.” Accessed April 26, 2018.

Mapping Contact Patterns at a Dressage Show in Ontario

Taking a break

Show season is here! You and your horse will travel to a local show, perhaps to another state, or even across the country. Your horse is vaccinated, registered, and ready to go. You know there is a potential for exposure to disease, so at the show, you try to limit his contact with other horses. If you could see the pattern of potential contacts at the horse show, what would it look like?

Using network analysis, a method from social media research, researchers at the Ontario Veterinary College, University of Guelph described the network of contacts between horses at a 2-day dressage show in Ontario Canada.

Ninety-six competitors kept their horses in three different locations at the show – an outside covered arena (cover all), a barn, or a trailer in a field. Show attendees completed a questionnaire about contacts with other horses. Using the answers from the competitors, the researchers developed a network graph (see figure). The figure shows the relationships between the three locations at the fairgrounds, the horses attending the show (primary contacts), and the horses stabled at the home facility (secondary contacts). The lines represent connections between horses and locations.

From: Descriptive and network analyses of the equine contact network at an equestrian show in Ontario, Canada and implications for disease spread. BMC Veterinary Research. Authors: Kelsey L. Spence, Terri L. O’Sullivan, Zvonimir Poljak and Amy L. Greer. Ontario Veterinary College, University of Guelph.

The graph shows a high degree of connectivity from horses from the home location (the black dots). The horses attending the show (blue dots) have a less dense pattern. “Only 8% (69/820) of the nodes in the network represented horses that were competing at the show, while 87% (710/820) represented horses stabled at individual home facilities,” according to the authors. The “home barn” contacts represent additional opportunities for contact, in addition to the relatively sparse connection density of horses at the show.

This, according to the researchers, is something to keep in mind when considering strategies for disease intervention and biosecurity. “Simply planning disease intervention strategies based on the horses that attended the show without explicit consideration of secondary contacts would severely underestimate the resources required to control a potential outbreak,” say the authors.

Visualizing equine contact patterns the same way we visualize social media contacts or computer local area networks could be helpful in determining biosecurity policies and heading off disease outbreaks.

The paper is freely available on the BMC Veterinary Research website. You can read it here.
Descriptive and network analyses of the equine contact network at an equestrian show in Ontario, Canada and implications for disease spread.