Horse Spring Grass: Problems & Solutions

Horse – Spring Grass

It’s wonderful to see green shoots sprouting again after the gloomy winter months. Instead of having to haul heavy hay bales around the barn, we can finally let our equine buddies graze all day. But the transition from hay to spring grass can bring complications with it. Not all horses cope well with the sudden switch, and appropriate management may be necessary if negative symptoms appear.

The Problems

Intestinal

Spring grass contains sugars, protein and carbohydrates in much higher levels than are present in most hay types. Overloading the horse’s digestive system with these nutrients upsets the sensitive balance of micro-organisms in the intestinal tract.

Cool season grass (such as spring grass) contains fructan, a complex and easily fermented sugar. As Kentucky Performance Products explain:

“Instead of being digested in the foregut, fructan passes into the horse’s hindgut, where it ferments and causes the production of lactic acid. Too much lactic acid reduces the pH of the hindgut, and these changes “negatively affect the delicate microflora that live in the hindgut and aid in digestion.”

This can lead to bloating, diarrhea, colic and laminitis (see below).

Obesity

Many horses continue to eat well during the winter while getting little or no exercise. Spring grass puts these already plump animals at high risk of becoming obese. The incidence of obesity in horses is upwards of 45%. Being chronically overweight has many adverse effects on horses, including:

heart disease
lung problems,
intolerance to exercise
inefficient thermoregulation (over-heating)
obstructions in the intestinal tract
colic
insulin resistance (see below)
EMS (equine metabolic syndrome)
laminitis

Incorporating an exercise routine with a horse exerciser can help during the winter months.

Insulin resistance

Insulin is used by the body to metabolize sugar and starches (carbohydrates). When a horse is insulin resistant, its cells no longer respond to the insulin. This results in wasting of the muscles. Other signs of insulin resistance include:

fatty deposits, particularly on the crest, rump and over the eyes
polyuria (excessive urinating)
polydipsia (excessive drinking)
insatiable appetite
laminitis

If caught in time, insulin resistance is reversible through weight loss and exercise, according to Zoe Davies MSc.Eq.S.,R.Nutr. So seek prompt veterinary attention if your horse shows signs of IR.

Laminitis

Laminitis can be an extremely painful condition for horses. Symptoms include:

The horse is uncomfortable standing in the same position for any length of time and constantly shifts his weight from one leg to the other.
The horse appears to be trying to take the weight off his front legs
Choppy and/or stiff gaits.
Shortened strides on harder surfaces which were not problematic for the animal in the past
Soreness in the back, even though the saddle fits properly

Consult your vet immediately if you suspect your horse is suffering from laminitis.

A Hot Horse

Many riders notice that after grazing on spring grass their horses become spooky, nervous and excitable. In extreme cases they are impossible to ride. In addition to the sudden increase of sugar in their diet, the cause of this behavior is the insufficient level of magnesium in spring grass. Performance Equine, in Magnesium: The Mineral Superhero describes it as being “by far the most important mineral, activating over 300 different biochemical reactions all necessary for the body to function properly.” It’s not surprising that the lack of such an important element can lead to bad equine behavior.

The Solutions

Pre- and Probiotics

These can help the horse’s digestive tract function correctly by maintaining the microbial balance in the hind gut.

Prebiotics, as Triple Crown Feed explains, “are not microbes, but ingredients that help the microbial populations in the hindgut remain stable and healthy. A prebiotic …… enhances the quality of the microbe population that’s there.”

Probiotics are micro-organisms which, when fed live to the horse, introduce viable ‘good’ bacteria and encourage a healthy digestive environment. Check that the cultures in any probiotics you choose were not killed while being processed. Horses appear to benefit more from a continual supplementation of probiotics to their diet than occasional use. Companies such as Succeed or SmartPakEquine sell high quality equine digestive supplements.

Restrict Grazing and Feed Hay

It’s a good idea to alternate grazing with feeding hay while the young grass is coming through. There are certain times of day when it is safer to let your horse graze,such as the morning when the daytime weather is sunny with warm nights, and on rainy, wet days. Give hay each time your horse comes off his pasture. The slow fermenting fiber will help counteract the effects of the fast fermenting sugars in the spring grass.

Reduction of Feed

Eleanor Kellon, VMD says that “for ideal health, your horse should be maintained at a body condition score of 5.” She is referring to the Henneke body condition scoring system which describes the ideal horse this way:

Neck blends smoothly into body
Withers are rounded over spinous processes
Shoulder blends smoothly into body
Ribs cannot be visually distinguished, but can be easily felt
Back is level
Fat around tailhead beginning to feel soft

If you reduce your horse’s feed, ensure he still receives enough nutrients. Talk to your veterinarian about how best to safely bring down his weight if he’s getting fat.

Introduction of Low Starch Feed

For obese or insulin resistant horses low starch feeds are a good solution. They also prevent the sudden sugar rush some horses get from regular feeds. This makes them more excitable and nervous, especially if they’re already getting a sugar high from the grass, and leads to other health issues. Discuss with your vet about using nutrition to help avoid the onset of problems due to spring grass.

Addition of Magnesium Supplements to the Diet

Spring grass is higher in potassium and nitrogen with less magnesium than more mature growth. Among its many functions, magnesium is essential for the regulation of blood sugar levels and the thyroid. Insufficient magnesium is partly responsible for equine metabolic syndrome and obesity, both of which can lead to laminitis. And as we discussed above, a lack of magnesium can create severe behavioral issues. You can redress the balance by supplementing your horse’s diet with a magnesium product such as Quiessence from SmartPakEquine.com or MagRestore from Performance Equine. Spring grass presents tough health challenges for some horses, but there is much you can do to offset them.