By Dr. David A. Rustebakke

            Although nature has equipped horses to deal with extremes in temperature, there are a number of things you can do to make winter easier on your horse.  While you are winterizing your home and vehicles, also think of winterizing your horses.
 
            Horses do not perceive cold to the same degree that we do.  Nature has equipped the horse with the ability to acclimate itself to the average winter temperature.  A healthy horse in a good state of nutrition with a normal, healthy hair coat is perfectly comfortable at temperatures in the 20's and 30's in the Lewiston Clarkston Valley.  I was raised in Eastern Montana where winter temperatures were commonly 10 to 40 degrees below zero; the horses there grew much heavier hair coats, and appeared to be comfortable at those temperatures.  
           
            In a nutshell, the key to winterizing a horse is to allow him to acclimate to the prevailing temperatures, provide shelter to protect him from the wind and moisture, and minimize other stressors (the cold weather is enough stress, he doesn't need other health problems to add more stress). 
 
            Some sort of shelter is necessary.  Wind chill and loss of insulating ability due to a wet hair coat make the temperature appear much colder than it is.  Horses turned out on the range can find a canyon, bluff, or trees to escape from the wind; a horse confined to a small pasture has only what you provide for him.  Shelter does not need to be elaborate; a 3 sided shed with a roof is adequate.
 
            Blanketing is no substitute for shelter.  If done improperly, it can actually be detrimental in that it keeps the horse from becoming properly acclimated to the prevailing conditions.  The purpose of blanketing is to prevent long hair growth in horses that are being shown, to provide some warmth while trailering or during colder than usual weather, or to cool out a hot horse in cold weather.  A good waterproof well insulated blanket is useful during an unusually cold period; horses that are well acclimated to the 20’s and 30’s of a typical Lewiston Clarkston Valley winter will appreciate a warm blanket on those rare nights when it dips down near zero, or below.  However, long term blanketing of an un-sheltered horse may actually prevent growth of a proper hair coat, and can actually increase the chances of the horse becoming chilled. 

By Dr. Rustebakke

 
            Veterinary Medicine and Animal Nutrition are separate specialties in the animal care industry; however in my career I have found that in order to give good health care advice I need to know something about nutrition. As primary care health providers to these animals, the veterinarian is the one who actually has eyes on the animals or on the herd, and we are in the best position to diagnose a nutritional problem and recommend  specific products to help solve a problem.  Many of us in practice are not familiar with all of the products available, and few of us actually have extensive training in nutrition.  Because of this, our best option is often to refer the owner to a nutritionist to help you formulate a proper ration.
 
Nutritional based diseases seen in a typical veterinary practice
 
            Malnutrition or under nutrition is by far the most common problem I see.  This is often a result of ignorance (as opposed to willful neglect) on the part of the owner.  These horses are often presented to look for a reason for weight loss.  Most of these horses have dental problems, which we correct as well as possible.  However the dental problems are often not severe enough to be the entire reason for the weight loss.  To fully work up these horses we do a thorough physical examination including taking the vital signs (temperature, pulse, and respiration, listening to the heart and lungs, assessing body condition, hydration, capillary refill time, look for chronic pain issues, see if the stated age corresponds with the age estimated by the teeth, etc..).   If no obvious problems are noted, we recommend a blood test (serum chemistry and CBC) to look for any chronic infections or organ system failure.  If we identify a specific disease condition, the recommendations are based on whatever disease we see.  Otherwise, the next step is to assess the diet and recommend changes.
 
            From here, this is not rocket science.  We know that a horse requires a certain number of calories per day for maintenance, and a few more calories for work or production.  This can vary from 15 Mcal per day for an average sized horse at maintenance to over 30 Mcal per day for a horse working hard, or in maximum lactation.  The problem with most of these horses is not a lack of vitamins or minerals or other micronutrients or probiotics; the problem is a shortage of calories.  They may be lacking vitamins, minerals, etc. but that is not why they are thin; they are thin because they are not getting enough to eat.  They may or may not be getting enough pounds of feed (2% of body weight per day is the common recommendation).  But many of the forages do not have the energy density to provide the required caloric intake at the 2% level.  So the solution is to increase the energy density.  That is when I refer them to the feed store to provide them with products that will increase the energy density without causing secondary problems.  There are a myriad products out there designed to do just that.  It is important to use a product that is safe, which means combining soluble carbohydrates such as found in grain products, with digestible fiber and fat.  Most of the commercial products out there, if fed as per the manufacturers label instructions, also include the required vitamins and minerals and often other products to make the entire diet more digestible as well. 
 
            Over nutrition and obesity is the next most common problem that I see in practice.  This is also often due to a misguided sense of what is good for the horse.  A few of these in my practice area are due to the unreasonable breed standards required by halter classes in horse shows.  There is nothing I can do to solve the obesity required by the AQHA halter horses...