PREVENTING GRASS FOUNDER

“Grass founder” is a problem of the horse that is overweight.  Rarely does the young (under 5) or active "using" horse have a problem.  The metabolism of the young horse is running at such a fast pace it burns calories rapidly.  The using horse is similar.  At whatever age they are, if they are being used frequently (more than once a week!) they will be physically fit; with that comes an active metabolism and usually a thyroid that is functioning properly.

You have a good idea as to the maintenance requirements for your horse.  Does it take large amounts of a dense feed plus good hay to stay in good condition?  By good condition we mean they will pass "the rib cage test?"  When you lay the flat of your hand on the rib cage, you may feel the individual ribs.  They should have a thin fat cover over them.  As a result you will feel the ribs but with a cushion over them.  This will be a thin deposit of fat and when you move your hand around the skin moves easily due to lubrication from the fat.  If you cannot feel any rib at all, there is too thick of a fat cover present.  At this point there will also be fat deposited over the crest of the neck.

As we discussed last week, these deposits are held in reserve for a time when they will be needed--which is usually never. This fat can be very difficult to remove.  In fact, about the only way to remove a heavy crested neck is for the horse to suffer a major medical problem, be aggressively exercised, or have a foal.  The latter is not an option for the boys of the group.  But for the mares, nursing will draw the fat off very efficiently if we can resist the temptation to increase the grain because they are nursing. Of course the really heavy mare can present challenges to becoming pregnant.

The easy keeping horse is usually the one most at risk of foundering when the new grass becomes available.  If your horse is in this group there are several thing we can do to prevent them from foundering.  First and most important is to reduce their calorie intake.  If you are feeding grain, either stop feeding it or change to a very low fat grain.  The fat level of corn or oats is three percent.  Some of the all grain mixes will be less due to the filler added.  If additional fat is added, as in some of the senior feeds, the percent will be six or above.

If Dobbin has you trained to give him some feed everyday, keep the portions small.  Due to the weight of oats, you can feed a cup of oats and provide fewer calories than with a cup of all grain or corn.  Bran is also a very low calorie feed and a very good bulk former.  If you have ever tried it yourself you will be surprised any horse would eat it,  and you are right!  It may need to be mixed with a little sweet feed for flavor and to reduce the dustiness.

To really put the horse on a diet, you will need to confine it from the grass now and continue to keep it confined until the heat of summer slows the growth of the grass.  Once the grass becomes mature and stemy, the
digestibility will drop.  While your horse is in the fat ladies' pen, she will need to be fed hay.  The objective of the hay is to give them "something to do" and to keep the bowel active.  So a low quality hay will do just fine: something such as "the year before last year's" fescue hay.  They will sure turn their noses up at it until they begin to realize you are not going to give in.  They can probably eat as much of it as they want if it is truly a low quality hay.  Ideally the calories needed to digest it will be less than the calories derived from it.

Remember, many of the "easy keeping" horses or those with a history of founder have other problems as well. The hypothyroid or "Cushings diseases" can be diagnosed by blood tests and treated with appropriate therapy.  Prevention is the key to better health and longevity of the older horse.