By Dr. Tania Cubitt and Dr. Stephen Duren, PhD

As we welcome the transition from winter to spring, we are eager to get back in the saddle and start riding regularly again. Canadian winters are not sympathetic to outdoor riding, and without access to indoor facilities many horse owners have not been able to ride or exercise their horses as much as they would like during the winter months.

Bringing horses back into work after their winter vacation must be done gradually by starting at a lower level and increasing the duration and intensity of workouts. At the same time, the horse’s feed should be adjusted to address his present body condition (too thin or too fat) as well as nutrient requirements for the increased workload. It doesn’t matter what your horse’s level of fitness was when you stopped riding last fall; after three or more months of inactivity, the conditioning he had is essentially lost. Even if the horse had plenty of turnout, most horses do little more than eat and stand around, especially when the weather and ground conditions are poor. 

Your horse should have a spring checkup including a visit from the veterinarian and farrier to ensure he is healthy and ready to go back to work. Photo: Pete Markham/Wikimedia Commons

Here are a few simple guidelines to safely bring your horse back to work after a prolonged break.

Make Feeding Changes Gradually 

The horse is first and foremost a grazing animal that relies extensively on the bacteria present in its gastrointestinal tract to process forages. These bacteria are a mix of different organisms that work together to the benefit of the horse. If the feeding program is changed suddenly, bacteria populations do not have time to adjust. Instead, large numbers of bacteria die, while others flourish, setting up a situation where toxins may be absorbed by the horse, resulting in digestive upset or colic. Many horses are as sensitive to changes in hay as they are to changes in grains. A gradual change from one feedstuff to another provides time for the bacterial populations to adjust. For example, when changing the type of hay or grain being fed, replace only about 20 to 25 percent of the current feed every other day, so that it takes a week or more for a complete change.

Be Careful Not to Overwork 

A horse that hasn’t seen much exercise over the winter can be just as excited about going out on that first ride as you are. But be careful not to mistake that eagerness for fitness and allow the horse to do more than he is physically conditioned to do because odds are he will, and in a day or two his muscles will really be feeling the effects.

Muscular aches and pains are not something you will readily see, but they will manifest themselves as back and gait stiffness, sluggishness, poor attitude toward work, and the development of vices and refusals. These can progress into sporadic episodes of tying up or exertional rhabdomyolysis.

The snow is melting and there’s warmth in the early spring sunshine. It’s time to start bringing your horse back to fitness with a gradual return-to-work program. Photo: ©CanStock/Iofoto

Sporadic exertional rhabdomyolysis occurs most commonly in horses that are exercised in excess of their level of conditioning. This happens frequently when a training program is accelerated too abruptly, particularly after an idle period of a few days, weeks, or months. Increased exercise on random hot, humid days may also elicit sporadic exertional rhabdomyolysis in susceptible horses because of high body temperatures, loss of fluid and electrolytes in sweat, and depletion of muscle energy stores. In some instances, horses seem more prone to exertional rhabdomyolysis following respiratory infections. Therefore, horses should not be exercised if they have a fever, cough, nasal discharge, or other signs of respiratory compromise. A well-designed gradual exercise program and a nutritionally balanced diet with appropriate caloric intake and adequate vitamins and minerals are the core elements of treating sporadic exertional rhabdomyolysis. 

As horses work more their need for water will also increase, so make sure the horse has free access to clean, fresh water. Water and electrolyte loss through sweat can cause the horse to perform poorly and in the acute cases can make him become seriously ill.

Shedding a Few Pounds 

In horses and ponies, eating less and exercising more are key elements for weight loss. Set realistic goals for weight loss and regularly monitor progress. Horses and ponies are individuals and will lose weight at different rates. Be patient; he didn’t get fat overnight and he won’t lose it all overnight either. As a guide, an effective weight loss regimen for a mature, light breed horse should result in the loss of approximately 55 to 65 lbs over a four to six week period. This decrease in bodyweight may be accompanied by the loss of about one unit of body condition score (BCS). 

Body weight (scale or by use of a weight tape) and body condition should be assessed regularly e.g., every two to four weeks during the weight reduction program, so that progress can be monitored and the program amended as required. Taking photographs of the horse and comparing before and after shots can also help assess body condition visually. The body condition scoring system uses a 1 to 9 scale where 1 is emaciated and 9 is obese; optimal is considered to be a score of 5 or 6 (see sidebar: Body Condition Scores).

As a first step toward weight loss, incorporating exercise without altering diet can sometimes be sufficient to get your horse to an ideal weight. If feed restriction is also needed, grain and other concentrated sources of calories (e.g., commercial sweet feeds, and feeds containing added fats) should be totally removed from the diet. Excessive feeding of other treats such as carrots and apples also should be curtailed. Forage should be the primary, if not the sole, energy providing component of the ration. Low intake, low calorie ration-balancer feeds complete with vitamins and minerals should be used to supplement deficiencies in vitamins and minerals that exist in most hays and pasture.

Increasing Body Weight 

The very thin horse with a body condition score of 1 or 2 at the end of winter should be placed on a gradual increased level of nutrition in order to restore body weight. It takes 35 to 45 pounds of weight gain to change a horse’s body condition score by one unit (based on a 1100 lb horse). Therefore, a horse with a body condition score of two would need to gain approximately 132 lbs to increase its condition score to a five. This would take around six months to achieve safely. When feeding large quantities of grain in order to increase the energy density of the ration, we must be careful not to feed more than five pounds of grain in any single feeding. Large grain meals pass more quickly than smaller meals through the digestive tract. Therefore fewer nutrients are absorbed and potential digestive disorders such as colic can occur. If the horse had a body condition score of three or four at the end of winter it would obviously take much less time to get his body condition to an optimal level. Based on the assumptions outlined above, it would take this horse approximately two to four months to achieve an optimal body condition.

Using calories sources such as highly digestible fiber sources and fat supplements will help increase the caloric density of the feed without adding extra bulk, and will help your horse safely gain weight faster than by simply adding extra grain.

Alfalfa hay has more calories per pound than most grass hays and is an excellent addition to a weight gain feeding program. Fat supplements such as vegetable oil or stabilized rice bran are much more energy dense than cereal grains. Vegetable oil is 99 percent fat, while rice bran is approximately 20 to 25 percent fat. Adding a fat supplement to the diet will also help improve skin and coat condition, especially after a cold, dry winter. 

In summary, when bringing horses back into work, we want to make all feeding changes gradually. Avoid overworking the horse beyond its fitness level, and allow adequate time for the horse to regain or lose weight to return to optimal body condition.

Main Photo: ©Canstockphoto/Melory