Horses

Health and Care

It is important to establish an annual health care program with a local veterinarian with horse expertise.

This section is summarized from Introduction to Horse Health - Purdue University 2002.

Exercise

• Horses need to be conditioned for activities, as well as warmed up and cooled down, like any athlete
• If stalled, a horse should go outside for at least 1 hour each day
• Don't allow your horse to eat a meal or drink unlimited water immediately after exercising. Horses must be cooled down first in order to prevent colic

Vaccine Overview

• Vaccinate horses annually for tetanus, Eastern and Western Cephalomyelitis, West Nile Virus and rabies
• Talk with your local veterinarian about the benefits of disease risk-based vaccinations that may vary by region, for example: Equine Herpesvirus, Equine Influenze, Leptospirosis, Rotaviral Diarrhea, Strangles, etc.

Parasite Control

• Internal parasites can be controlled with deworming programs and proper waste and pasture management
  • Methods of deworming include: oral tubes of paste (most common), feed additives, and stomach tubes (performed by veterinarian)
  • Work with your local veterinarian to develop and monitor a parasite control program that is designed to prevent illness, minimize shedding of parasite eggs, and maintain effectiveness of dewormers
• The most common external parasite that impact horses are flies
  • Horse and deer flies can be a vector for serious equine disease and can cause stress for horses
  • Fly sprays, sheets and masks can help reduce bites and fly traps can reduce populations

Dental Care

• Have your veterinarian check teeth at least once a year
• If teeth wear unevenly, they will need to be floated (filed off) to prevent weight loss and choking
• Other potential issues your veterinarian will look for include abscesses or impacted teeth

Hoof Care

• Hooves grow about 3 - 5 inches per year.
• If you are riding your horse on rough surfaces/roads that would wear the hooves faster than they can grow, the horse will need to be shod (shoes put on)
• In dry conditions, hooves may become brittle
  • the horse can stand in mud or water to moisturize hooves
  • there are many hoof care products commercially available that treat and prevent dry hooves
  • if a crack is noticed, a vet or an experienced farrier should be contacted for treatment
• In wet conditions, or when horses stand in manured mud, they can get thrush- a bacterial disease of the frog of the hoof that causes lameness
  • to treat thrush, move horse to a dry site and pare out the damaged hoof and apply copper sulfate or lime to dry it out/kill bacteria

Laminitis

• Laminitis (sometimes called founder) is an inflammation of the soft tissue (laminae) that connects the hoof wall to the coffin bone on the hooves 
  • in severe cases, the coffin bone will rotate and sink, which can cause the bone to break though the sole of the hoof
• Laminitis can be caused by overfeeding, stress or systemic illness
• Signs of laminitis: shifting of weight off front feet, heat in front feet, general signs of distress
• It can be easy to overfeed a donkey, pony or miniature horse leading to foundering/laminitis, so it's important to feed them the appropriate amount

Colic

• Colic is a symptom of a disease, usually in the gastro-intestinal tract, that causes a horse to show signs of abdominal pain
• Signs of colic: frequently getting up and down, frequently looking at abdomen, attempting to roll, refusal of food, lack of bowel movements, sweating, etc
• Contact your veterinarian immediately if your horse shows signs of colic

Fencing and Housing

Table 1: Minimum stalls sizes for confined horses. Table from Minimum Standards for Horse Care in the State of California 2023.

The stall sizes above are the minimum required space for one horse. Horses confined in this amount of space should get at least 1 hr/day of free turnout time or 15 min/day of controlled exercise (hand-walking, lunging, riding, etc). Excess feces, urine and mud must not accumulate within enclosures.

Nutrition

Maintaining a healthy weight for a horse (not underweight nor overweight) is essential for their overall health and longevity.

• If overweight, horses can founder (see explanation in Health section)
• If underweight, horses are more likely to have other health problems and not have as much energy to exercise
• If horses aren't exercised more than once a week, they do not need to be fed grain

Stage of Production/Growth of 1,100 lb horse (mature weight)

Table 2: Nutrient requirements for horses in various stages. Table adapted from Nutrient Needs of Horses from Oklahoma State University where nutrient requirements were estimated from the National Research Council’s Recommendations for Nutrient Requirements of Horses (2007).

Hay should be dry, dust-free, soil-free and mold-free. Horses will eat between 1.5 - 2.5% of their weight each day in dry forage. Therefore, a 1,000 lb horse will eat between 15 and 25 lbs of dry hay each day.

• Alfalfa hay is a legume, not a grass, therefore it is high in protein and calcium
• Alfalfa hay must be balanced with less calcium rich hay, such as oat hay, bermuda hay, or fourway grass hay, to prevent colicing from calcium build-up in the horse's gut
• One easy way to achieve this balance is to feed your horse half alfalfa hay and half grass hay

Table 3: Typical nutrient content of various hays that are fed to horses. Table adapted from Choosing Hay for Horses, University of Kentucky Cooperative Extension.

Reproductive Cycle

Horse breeding is a complicated process. For the safety of the mares and stallions, it should only be performed by experienced breeders. Pregnancies can range from 320-360 days.

Mares are seasonal breeders, impacted by light and temperature, with their peak reproductivity falling around the longest day (June 22) and having an anestrus period during the winter, when they don't cycle. Before and after winter anestrus mares goes through a transitional period before they have regular cycles. Typically, a smooth, summer coat is a sign that a mare has started ovulating, or having estrus cycles.

The reproductive cycle of a mare is approximately 21 days; estrus is 5-7 days, when the mare is receptive to a stallion. At the end of the estrus, ovulation occurs, which is when breeding (via live cover or AI) should occur.

In order to determine where the mare is in her cycle and predict the timing of ovulation, repetitive ultrasound scans of the ovaries and uterus have to be performed.