Unfortunately, there are instances where a horse may be starved. This may be due to owner neglect, a lack of education on what a horse’s dietary needs are, or medical in nature.  Regardless, when a horse is starved, the animal must be treated carefully and properly fed to bring it back to proper health. If a starved horse is fed improperly, usually overfed too quickly, it can die. Thus, caution is key with a sound health plan developed with your veterinarian.

What Does Starvation Look Like in a Horse?

Starvation differs from malnutrition in that malnourished horses are being offered feed but not enough to meet their daily nutrient needs. Starvation is when a horse is denied access to any type of feed that they can consume. Both can be debilitating to the horse and lead to serious health consequences and eventual death.

The number one indicator of starvation or malnutrition is a low body condition score (BCS). The Henneke Body Condition Scoring System is the gold standard for evaluating a horse’s dietary status.  Briefly, the scoring system ranks horses on a 1 (poor) to 9 (extremely fat) scale. The ideal BCS range is 4 (moderately thin) to 6 (moderately fleshy), with an ideal score of 5 (moderate). Competition horses may fall to a score of 4, whereas breeding animals and others are closer to a 6. Malnourished horses that are still being offered feed can fall into the 3 (thin) to 4 range. Starved horses or those severely malnourished will drop below a BCS of 2 (very thin).

In addition a BCS score, which evaluates condition or fat cover on horses,  Tribute’s Equine Nutrition Wellness System takes this a step further and also evaluates the crest and topline of the horse. The crest score is used to evaluate fat along the crest for an indication of equine metabolic syndrome. The topline evaluation is used to calculate topline muscling and amino acid status. Malnourished and starved horses will generally score poorly with this system, with few fat deposits along the crest and have a topline score of 0 or possibly 1. The spine will easily be seen and felt, with the topline muscles significantly shrunken.

Coupled with poor body condition, starved, or malnourished horses will be lethargic and inactive, have poor coats, brittle hooves, dull eyes, elevated heart or respiration rates, and overall look unwell. Even horses with a BCS score of 4 or higher can be malnourished. Thus, if you are concerned about malnourishment in your horse, our article on  Could You be Underfeeding Your Horse is worth a review.

What Are The Health Dangers of Starvation in Horses?

The most obvious danger to any horse that is starved is impending death. Because the animal is not receiving any nutrients, the body begins to catabolize (breakdown) its body tissues to survive. Once the horse’s carbohydrate reserves are used up, they turn to fat. This is because fat is usually one of the most readily available forms of energy during starvation. In fact, within 24 hours after withholding feed, a horse’s metabolism begins to change as it mobilizes its fat reserves. For short term, this generally does not result in any lasting harm. However, in prolonged energy deprivation, horses will experience “hyperlipidemia.” This can result in long-term damage to horse kidney and liver function and overall health.

Another major source of nutrients for a starving horse is its muscles. To support continued body function, starving horses will begin to catabolize their muscles once their carbohydrate and most of their fat reserves are depleted. The horse will begin to break down not only skeletal muscle protein, but other tissues like cardiac muscle around the heart and smooth muscles throughout their body. Another alarming factor of starving horses is they will even begin to leach minerals and other critical nutrients from their bones and other body tissues. The horse is literally digesting themselves to survive.

What is “Refeeding Syndrome” and How To Avoid it in Horses?

Our instincts when we rescue a starved horse is to immediately feed it as much food as it wants. However, this can quickly overwhelm the horse’s body as it has adapted to being starved. Not to mention a sudden large influx of feed into the digestive tract can lead to digestive disorders like colic.
Refeeding syndrome happens when insulin in response to a sudden supply of glucose begins to take nutrients from the bloodstream and stores them in the cells. This leads to a quick and rapid depletion of key nutrients in the bloodstream. The lack of these critical nutrients in circulation can lead to:

  • Hypocalcemia: Lack of circulating calcium leading to irregular heart function, muscle twitching, rapid breathing, and stiffness. 
  • Hypomagnesemia: Lack of circulating magnesium leading to neurological disorders with behavioral changes.
  • Hypokalemia: Lack of circulating potassium leading to heat failure, muscle weakness, muscle seizures, or collapse. 
  • Hypophosphatemia: Lack of circulating phosphorus leading to muscle weakness, joint pain, irregular heart function.

With a sudden drop in key nutrients in the bloodstream, the horse can suffer cardiac arrest and die. Thus, it is extremely important to remember that a slow introduction of feed is critical for any starved horse if they are to survive.

The key to any rehabilitation plan for a starved horse is to discuss all options with your veterinarian. Data indicates that starved horses that lose 30% of their body weight can and do recover. For those horses that lose more than 50% of their body weight, the prognosis for survival is quite poor.

As mentioned, the key is a careful and slow reintroduction of feed. Data from the University of California at Davis has led to a careful feeding management plan for starved horses. They recommend:

  • Day 1 to 3: Feed 1 lb. (0.45 kg) of alfalfa hay every 4 hours, not to exceed 6 lbs. (2.72 kg) per day. Have your veterinarian monitor daily.
  • Day 4 to 10: Slowly increase alfalfa hay and decrease total number of feedings so that by day 6 the horse is eating just over 4 lbs. (1.81 kg) of hay every 8 hours, not to exceed 13 lbs. (5.90 kg) of alfalfa over 24 hours.
  • After day 10: Allow free access to as much alfalfa hay as the horse can consume. Slowly introduce a concentrate feed when the horse is deemed in recovery by your veterinarian. A moderate fat and higher fiber feed (i.e., Tribute’s Kalm ‘N EZ) would be the most appropriate choice for a starved horse in their recovery phase. The addition of pre- and probiotic are an added benefit to rehabilitate gut flora.

It is also always recommended to provide the horse free access to clean and fresh water. Owners are cautioned not to introduce exercise too early. Daily hand walking can be beneficial until the horse is at minimum in a BCS score of 3. Then, once at or near a BCS of 4, the horse can undergo forced exercise to help muscle recovery and growth.

Take Home Message

It is heartbreaking to see a starving horse, and it is more common than we would like to see. However, with intervention these animals can and do recover. The critical take away message is to always work closely with a veterinarian during the recovery phase for a starved horse. They must be carefully and slowly be brought back to proper body condition. It is also advisable to discuss a suitable recovery plan with a qualified equine nutritionist. The Tribute team is always available for advice and please feel free to contact us for any help.

 
References
Stull, C. 2012. Nutrition for Rehabilitating the Starved Horse. University of California, Davis.
 

CHRIS MORTENSEN, PH.D.