Monthly Archives: August 2013

Equine Nutrition Part 2: Hay

collecting hay sample

Dr. Parisio collecting a sample with a hay corer.

For many horse owners in this area of New Jersey, hay remains the largest forage source available.  Most horses should consume 2% of their body weight in forage daily.  This equates to the average 1,000 lb. horse typically eating as much as 20 lbs. of hay per day.

Given that hay comprises the largest and most important component of a horse’s diet, knowing the nutritional quality of this forage source is essential.

What to look for when buying hay

Characteristics to look for when assessing the quality of hay:

Leaf-to-stem ration: For most horses, hay with a high leaf to stem ratio is most desirable.  An indication of the maturity of grass when it is cut, younger, leafy grass hay contains more protein, energy and minerals than hay cut later in the growing period.  The higher the proportion of stems, the less digestible and therefore less desirable hay becomes.

Fresh smell and appearance: It is wise to always inspect the hay with your eyes and your nose before feeding it to horses.  Hay should not be yellow or brown in color, which could indicate that it is too mature or has been stored properly.  A moldy or sweet smell could indicate spoiling of the hay during storage.

Dust: If you shake out a flake and a dust cloud appears, making you want to sneeze, imagine what this can do to your horse’s respiratory tract!  Dusty hay is often the first trigger in chronic inflammatory airway disease in horses.

Examining your hay to assess the above qualities is an important first step.  However, the actual nutrient quality of the hay is much more difficult to determine.  There are several factors that can significantly impact the nutrient quality of hay and furthermore, your horse’s ability to obtain those nutrients.  What is the best way to find out?  Having your hay analyzed.

This process includes obtaining core samples of a representative portion of your total hay supply.  These samples, along with information on the type of grass hay and the cutting (1st vs. 2nd etc.) are sent to the lab for analysis.  The results are reported and interpreted as follows to highlight the most important nutritional qualities of hay:

Crude Protein: Protein is required on a daily basis for growth, maintenance, lactation and reproduction.

Neutral and Acid Detergent Fiber content: These measurements tell us how digestible the hay is. The higher these numbers are, the lower the digestibility of your hay.

Carbohydrates: Represents the amount of energy (starch) and other forms of carbohydrates in the hay.  Higher values may be unsafe for horses with metabolic disease, those who are obese, or who suffer from laminitis.

Minerals: Calcium, phosphorus, potassium, copper, and zinc are just some of the minerals we consider important in a horse’s diet.

Vitamins: Vitamins A, D, and E are all components in hay that horses need to stay healthy.

hay sample

A hay sample ready for analysis.

For most horse owners, hay will be the largest and most important expense factored into the daily care of their horse each year.  Therefore, it is essential to know that what you are buying and feeding to your horses is indeed of the quality you expect.  Whether you choose to have you hay sampled once a season or once a load, whether you share the information with multiple horse owners at a large barn, or stay informed about your own supply only, the analysis can provide information on how to feed your hay efficiently while adequately providing for your horse’s nutritional needs.