Heading into summer many of you will be contemplating the process of weaning your foals. Typically foals are weaned between 4-6 months of age and the process used is often dictated by the facilities available. Careful planning will reduce stress and set your foal up for success. Obviously the biggest change for your foal will be the loss of contact with its mother followed by the change in diet. At birth the foal’s sole source of nutrition is provided by the mare’s milk which at its peak can amount to 3% of her body weight per day. Over time the foal’s digestive tract matures. Bacteria are picked up from the environment and populate the hindgut. This provides the foal with the ability to start digesting more complex feeds such as pasture, quality hay or some other supplemental feed.
By 4 months a significant portion of the foal’s daily nutrient intake will likely be coming from these new sources. This shift away from the mares milk combined with the fact that the nutrient concentration in the mare’s milk is decreasing can lead to decreased rates of growth. This may be one motivation for weaning at 4 months especially for foals being produced for weanling sales and markets that demand large foals carrying condition. In these cases, it will be necessary at this time to introduce a fortified grain feed formulated specifically for growth.
Whenever weaning occurs, due to the stress involved and changing diet, there is the potential for it to cause a decrease in growth rate, which once the foal is established on its new feeding regime and lifestyle, bounces back.
Large fluctuations in growth rate have been associated with increased incidents of developmental orthopedic conditions such as osteochondritis dissecans (OCD). Therefore whether you are striving for a slow, moderate, or rapid (not recommended) rate of growth in your foal it is advised that this growth rate be steadily maintained before, during and after the weaning transition.
Regardless of the way in which you choose to wean your foal, one of the best ways to reduce the risk of changes in growth rate is to insure that the foal is aggressively eating its post-weaning diet prior to starting the weaning process.
In many management situations, foals have been steeling feed from their mother’s buckets for some time. This is just one reason why it is important that the mares supplemental feed is correctly balanced and suitable not only for broodmares, but also growing youngstock. For easy keeper mares this may be a high protein ration balancer, for those who are harder to maintain it may be a broodmare or growth type feed. Ideally if the mares feed is identical to that which will be fed to the foal after weaning, less adjustment to new feeds will be necessary, which will help to reduce stress.
If your foal has not had access to any supplemental fortified feed prior to weaning one should be introduced slowly at least 2 weeks before weaning begins. This will help to reduce the risk of digestive disturbances caused by rapid changes in diet. Commercial feeds fed to weanlings should contain 14-16% protein and contain soybean or canola meal to insure adequate lysine to maintain growth. Such feeds are typically fed at approximately 1lb of feed for each month of age, so 6lbs for a 6 month old weanling in combination with a quality forage source. Of course this amount should be reached slowly and divided into multiple meals. For those who do not want to feed this level of concentrate to their foals, or for foals who are easy keepers, a high protein (approx. 25-32%) ration balancer that provides the necessary essential amino acids, balanced minerals and a source of vitamins is recommended.
It needs to be mentioned that while excessive protein in the diet was thought to be a cause of OCD back in the 1970’s more recent research has shown that this is not the case. Traditionally higher protein diets also contained higher levels of starch and sugar which have been found to cause OCD. Most modern commercial weanling diets now provide adequate protein while also being lower in starch and sugar than their traditional counterparts.
Pay attention to your foal’s growth rate prior to, and after weaning in order to identify changes that might be problematic. This is best done by frequently weighing your foal and measuring their height. Few breeders own a scale, although they are not a huge expense and can be a very worthwhile investment for serious breeding operations. An alternative is to use a weight tape. While this is not completely accurate, it will provide you information about relative changes in weight.
Begin weighing your foal prior to weaning in order to build a picture of its growth trajectory and then continue to take measurements every 2 weeks to insure that the foal stays on a steady course. If the growth curve deviates from a smooth curve and appears to be dropping below what is expected, that is a signal to increase the foals nutrient intake. Conversely amounts of concentrate should be reduced if the rate of gain is too fast.
Mares typically do very well during weaning and may start to blossom and regain lost condition. However attention should be paid to the teats, checking for heat and swelling that may indicate mastitis. Weaning can be aided by reducing the mare’s grain intake the week prior to weaning as this helps to reduce milk production. Conversely, milking out mare’s provokes milk production and is not encouraged.
Actively planning for weaning, taking steps to minimize potential stress, and insuring a high quality diet before weaning begins are all things you can do to help make the weaning transition as smooth as possible with the least amount of impact for your foal. A nutritionist can help you select the correct feeds and supplements and to put together a step-by-step plan for weaning and beyond. Working with a professional insures that the building blocks your foal needs to grow into a strong and vibrant individual are in place.