11: Cardiovascular Health

Action Point: Be aware of the signs that may indicate cardiovascular problems in the horse.

Rationale: Heart problems are not common in horses, however, they are not immune to them. If any of the following changes are observed in a horse, it may be an indication of a cardiovascular problem.

  • Loss of condition
  • Increased fatigue during exertion
  • Shortness of breath
  • Increased rate or effort of breathing
  • Weakness occasionally resulting in collapse or fainting
  • Signs of fluid accumulation in the abdomen or beneath the skin of the lower thorax

Heart murmurs are generally the most common, and in most cases benign of the cardiac disorders that can afflict horses. The majority of heart murmurs are physiologic, or normal, and can occur in conjunction with an excited state or a bout of colic. More serious cases could be caused by turbulence or increased velocity of blood flow due to a leaky heart valve. A specialist will be able to determine whether a heart murmur is considered incidental or merits further examination.

Horses can also be affected by congenital heart defects that are present at birth. Though these are much rarer in horses compared to humans and dogs. The first sign of a congenital heart defect is usually a murmur heard within the first few weeks or months after birth. These include ventricular septal defect (a hole in the heart) and patent ductus arteriosus (which will resolve on its own in most cases) – again, congenital heart defects are very rare in horses. 

Degenerative or acquired heart disease, such as arrhythmiasatrial fibrillation, and valvular heart disease may occur in horses older than 5 years of age, and very rarely in younger horses. Although still relatively uncommon, acquired heart disease has a slightly higher frequency of occurrence relative to congenital heart defects.

Myocardial disease is toxic damage to the heart muscle following an infectious disease like strangles, influenza or an internal abscess, and in rare cases a severe dietary deficiency of vitamin E or selenium, or the ingestion of a toxic chemical found in cattle feed.

Thrombophlebitis, a firm clot in a small part of the jugular is the only vascular condition that affects horses. It is usually the result of repeated trauma to the jugular from repeated puncture of the vein, injections or use of a jugular vein catheter.

Aorto-iliac thrombosis is a condition that affects the hind limbs, resulting in signs of lameness, stiffness, weakness and abnormal gait. The result of a clot that forms where the abdominal aorta branches toward the hind legs, this condition is progressive and rarely reversible.

The Equine Power Plant Unequaled!

*refer to summary of article in Functional Anatomy - Week 5: Activities

11: Infectious Respiratory Diseases

Action Point: Understand the most common infectious respiratory diseases and how to prevent them from occurring.

Rationale: Respiratory conditions are fairly common and can have a significant impact on individual horse health and performance and, in the case of infectious diseases, can be easily spread. Prevention is the best measure in ensuring respiratory health.

Management decisions play a significant role in maintaining respiratory health and protecting horses against infectious disease. Best practices include, developing a vaccination schedule in consultation with a veterinarian, and implementing biosecurity protocols, i.e. isolate all newly arriving horses, and isolate horses with clinical signs immediately.

Respiratory  system diseases fall into two categories. (1) Infectious upper respiratory tract disease (IURD) primarily affect young horses and often occur in the form of an outbreak. The most common IURD conditions to be aware of are equine influenza virus, equine herpes virus, equine rhinovirus, sinusitis, and strangles. (2) Infectious lower respiratory tract disease (ILRD) affect any age of horse. Includes pleuropneumonia, lungworm, and parascaris equorum.

Respiratory Diseases in Horses: What You Can Do to Prevent Them

Slater, J. D. & E.J. Knowles. (2012). Ch. 14: “Medical nursing.” In K.M. Coumbe (Ed.), Equine Veterinary Nursing. p.246-285 John Wiley & Sons Incorporated 

Future post: non-infectious respiratory system diseases

10: Develop an Equine Wellness Program

Action Point: Develop equine wellness programs for each horse based on their individual needs.

Rationale: Developing equine wellness programs in consultation with a veterinarian will ensure routine care and monitoring of each horse’s health and serve as a proactive tool in disease prevention and early diagnosis and treatment.

The following elements should be included:

  • routine immunization
  • parasite control
  • nutritional consultations
  • annual Coggins testing
  • dental care
  • annual physical examination
Is Your Horse Enrolled in a Wellness Program?

Designing an Equine Wellness Plan for Your Practice

Zimmel, D. (2009). Ch. 5: “Equine Wellness Program.” In AAEVT Equine Manual for Veterinary Technicians. p.131-146. Wiley-Blackwell

10: Protecting the Horse’s Skin

Action Point: Learn about the most common skin conditions in horses, how to prevent, identify, and treat them (in consultation with a veterinarian).

Rationale: Skin conditions, although not usually fatal, can cause a great deal of discomfort and affect the quality of life and performance abilities of a horse. They may also be an indication of disease, which may be contagious, and in some cases, zoonotic, that is, transmissible from horse to human. Common causes of skin irritation in horses are allergens, environmental factors/exposure, external parasites, and in some cases, management practices.

Common skin conditions

  • Hives (urticaria) – may be acute or chronic depending on the cause
  • Atopic dermatitis – airborne allergens
  • Sweet itch (insect-induced dermatitis) – Culicoides aka “no-see-ums”
  • Pemphigus foiaceus – autoimmune disease
  • Bumps/nodules – insect bites
  • Rain rot/rain scald (dermatophilosis) – bacterial, contagious
  • Mud fever/scratches (pastern dermatitis) – bacterial or fungal
  • Alopecia
  • Photo-sensitivity/sunburn
  • Warts and sarcoids
  • Ringworm (dermatophytosis) – fungal, contagious
  • Mange – mites
  • Lice

Prevention tips

  • Keep horses clean and dry
  • Avoid keeping horses in wet, muddy pastures
  • Parasite control – internal and external
  • Pasture and manure management
  • UV protection
10 Common Skin Conditions

Equine Dermatology - Everything You Wanted to Know (and More) About Skin

Diagnosing equine skin disease

Structure of the Skin in Horses

09: Colic Prevention

Action Point: Identify any colic risk factors of current management practices.

Rationale: While colic isn’t entirely preventable, minimizing a horse’s risk of experiencing colic will have benefits for overall health and welfare. A great tool to assess current risks is the Equine Guelph Colic Risk Rater Healthcare Tool.

In just a few minutes, the quiz will assess a number of key factors in colic prevention, including turnout, activity level, feed, water, dental care, and parasite management, and provide helpful tips to improve areas of concern.


07: Stay Up to Date on Current Research

Action Point: Stay up to date on current research on lameness and other conditions by checking the following websites at least once a month.

American Association of Equine Practitioners

College of Veterinary Medicine and Biomedical Sciences

Merck Veterinary Manual

My Horse University

UC Davis Centre for Equine Health

Rationale: While thehorse.com provides a wealth of easily accessible information and summaries of current research, the AAEP and veterinary schools provide an additional level of scientific and academic information that will help increase personal knowledge and understanding of lameness and other health topics of interest as they emerge.

02: Equine Body Condition Score Poster

Action Point: Purchase an Equine Body Condition Score poster from TheHorse.com to display alongside the Horse Health Check poster.

A horse weight tape will also be an essential tool. This should be available at a local tack shop or can be ordered through Amazon.ca.

Rationale: Effectively monitoring the BCS of one’s horse(s) is an important tool in ensuring your horse is in optimal health and receiving proper nutrition. Ensuring your horse maintains a healthy BCS based on its breed, age, and workload will also play a role in detecting and preventing disease.

01: Health Resources

Action Point: Create a binder containing the series of Equine Guelph Information Sheets, including the Horse Health Check info sheet.  Purchase a Horse Health Check poster to display in a prominent place for quick reference.

Rationale: In striving to do what is always in the best interest of the horses, it is helpful to have accurate and current information available on a range of topics related to equine health, welfare, and management.

Having the Horse Health Check poster placed in the tack room or feed room will remind everyone a) to perform a health check on every animal regularly, and b) of the steps involved to accurately monitor and detect any changes in health.

Horse Health Poster by Art King & Gayle Ecker (www.EquineStudiesOnline.ca)