Caring for the Weanling Foal

by R. Paul Schwab, D.V.M. Kulshan Veterinary Hospital

Now that summer is here, the foaling season is quickly moving into weaning time for horses.  New stresses are placed on the foal including new diet, companions, and possibly a new home entirely.   This is also a phase of very fast growth and development that if not monitored closely can result in a lame horse, possibly for life.

Before discussing the weaning process, we should discuss some of the preparation before the foal is even born.  Vaccinating the mare one month prior to foaling assures that her colostrum has the maximum quantity and quality of antibodies to transfer to the foal.  These antibodies protect the foal from disease during the first few months of life until it begins forming antibodies on its own.  These maternal (from the mare) antibodies start to decrease about 4-6 months of age.   At this point is when we start vaccinating the foal to increase its own antibodies.   If we vaccinate too early, the maternal antibodies may actually destroy the vaccine before it has a chance to work.   The exception is the foal whose mother was not vaccinated at all.  Here is a recommendation of a vaccination schedule for the foal:

Notice that the Rhino and Influenza vaccines are given later than the others.  Research has shown that the maternal antibodies for these viruses may persist a little longer and the foal can have a better antibody response at this age.  Above all, consult your veterinarian for recommendations on vaccines for your situation and area. 

There are several theories and methods about the actual separation of the mare and foal.   Most people wean their foal between 5-6 months, but it can be earlier or later depending on the situation.  Some mares will wean the foals on their own when given the opportunity, but certainly don’t count on it.  You should separate the mare and foal completely so that there is no chance of the foal suckling through the fence.  Believe me, they will do it.  Putting the foal with other weanlings can help ease the stress of the move by providing companions.  An older, trustworthy gelding or burro works well, too.  Make sure that the fences are in good working order and that there are minimal farm implements in the field for the foal to hurt themselves on (we sew up a lot of weanlings some years).  

The mare can get stressed as well.  She has to suddenly stop producing milk after feeding a 300-500 lb. foal.   The best thing to do is to take her off of all her grain and/or alfalfa and just feed her pasture or good quality grass hay.   This will help her stop producing milk.  There is no need to treat the udder with antibiotics or express milk from the udder unless there is a problem or infection there. 

Nutrition is probably the most important aspect of caring for the weanling foal.  They will no longer have the good quality protein that comes from mare’s milk.  Before weaning they should be eating, without problem, good quality mare and foal grain and good quality forage.  They can stay on this after weaning.  Most sources recommend a 14-16% protein grain fed at not more than 0.5-1% body weight per day.  If you are feeding alfalfa hay or another high protein hay, you probably don’t need that much grain.  (Alfalfa hay generally can test from 20-24% protein). Most important, protein needs to be of good quality, not high quantity.  Some feeds may advertise high protein but it may be from poor quality sources.   Generally, if the feed is really cheap, the ingredients are too.

Weanlings should be consuming 1.5-2% body weight per day in forage.  Usually good grass hay or pasture, a quality grain designed for the growing horse, and possibly and vitamin mineral supplement will do.  Of course all horses, regardless of age, should have free choice access to a salt block and water. 

Nutrition of the weanling has a primary influence on Developmental Orthopedic Disease (DOD).  DOD is a group of musculoskeletal abnormalities of the growing horse.  They include acquired contracted tendons, osteochondritis dessicans, subchondral bone cysts, and epiphyseal dysplasia.    All of these problems can be directly linked to feeding practices.  Of primary concern is energy; diets high in grain and molasses can have too much energy, which may interfere with normal cartilage and bone development.  This can trigger joint or bone swelling, pain, tendon contraction, or even defects in the cartilage itself.   Protein, vitamin and mineral balance, and even genetics also play an important role in DOD. 

To avoid these issues, monitor your foal's weight and body condition closely.  Foals that grow at a more rapid rate are generally at more of a risk.  Also, heavy muscle breeds and larger breeds, namely Quarter Horses, Thoroughbreds, and Drafts, seem to have a predisposition to DOD.   Your veterinarian can help identify foals that may be having subclinical problems with growth and development or help you with feeding recommendations for your situation.  

Don’t forget about worms and lice.  Weanlings are of particular concern because they have poor resistance to parasites due to their age and stress level.  They also tend to be more curious and experimental, eating almost anything whether it be dirt or another horse's manure.  More aggressive deworming strategies may be needed depending on your particular situation.  Regular fecal checks done by a veterinary lab can help you decide how often you need to deworm.   Also, other efforts to reduce field contamination can help, including pasture rotation and periodic manure removal.

Last but not least, exercise.  Unless there is a specific problem with the foal, weanlings should be given free-choice exercise.  Generally, a large pen with good shelter will do for a living environment.  If they must be stalled, try not to confine them for more than 10-12 hours a day.  On the other hand, forced exercise is not good either.  Growing bones can be quite sensitive to strenuous exercise. 

Overall good nutrition, exercise, and preventative health care go a long way to ensuring a healthy and sound horse.

NOTE TO FAIR PARTICIPANTS:

Don’t forget to make sure you horse is current on vaccinations before taking them to the fair.  Preparation now can help prevent sickness later.  If they need vaccines, they should be given at least 10 days to 2 weeks before the fair to ensure adequate immunity.