STILLWATER - Like people who find themselves too often "cooped up in the office or house," weanling horses that are housed and managed in stalls need a well-planned daily exercise program. Weanlings are more individualistic than most classes of horses in their nutrient requirements and how they respond to different types of exercise, said Dave Freeman, Oklahoma Cooperative Extension Service equine specialist.
"The successful horse manager knows what is normal for each weanling, recognizes the needs to adjust nutrition and exercise levels and is quick to detect minor indications that may lead to physical problems," Freeman said. Healthy growth is a result from combining good genetics, nutrition and exercise. Exercise stimulates appetite so the foal will eat more. In turn, the feed helps the foal build muscle and bone, which also are stimulated to grow as a result of exercise. Weanling nutrition programs need to supply the right balance and amount of nutrients to support bone and lean muscle tissue growth without pre-disposing the young horses to large fat accumulations.
"Large amounts of fat deposition don't occur in many genetic lines because of the prioritization of nutrients for bone and muscle gain at this age," Freeman said. Some weanlings that are accustomed to eating small amounts before weaning self-regulate grain intake. Thus, they can be allowed access to grain throughout the day with little worry of founder.
"Some foals prefer to eat small amounts of grain throughout the day rather than consume a meal-fed grain immediately upon offer," Freeman said. "This is especially true with foals that had been creep fed before weaning. Many of these foals, in essence, 'self regulate' their intake with feed offered on a continuous basis without overeating or putting on too much fat." Freeman said this system works on some farms, provided the weanlings are managed as individuals and are consuming forage. Most weanlings consume between two and three percent of their body weight in total feed per day. This relates to 10 to 13 pounds of total feed per day (grain and forage combined) for a 450-pound weanling.
"At least 30 to 40 percent of the ration needs to be forage in the form of highly palatable hay or pasture," Freeman said. "In terms of nutrient concentration per weight of ration, total rations need to supply 13 to 14 percent protein, 0.5 percent to 0.6 percent lysine, 0.5 percent to 0.6 percent calcium and 0.3 percent phosphorus." Nutrient balance and the ratios of protein to energy, lysine to energy and calcium to phosphorus should be checked by equine nutritionists to ensure adequate protein and mineral intake at different energy intakes, said Freeman. Rations need to be highly palatable, clean, fresh and easily digestible. Forced exercise programs that use energy intake to promote healthy growth can differ in type, intensity and frequency.
"The goal is to allow the type of exercise at the intensity and frequency needed to stimulate growth of bone and muscle tissue without overexerting the foal's ability to respond positively," Freeman said. Examples of frequently used exercises include free access to a pasture; turning out a young horse into a pasture for limited amounts of time, either alone or with other weanlings; round-pen work; longeing; and ponying.
"Each can be used successfully, but some require more careful monitoring than others," Freeman said. Too much of the wrong type of exercise will cause the foal's body to fail, often resulting in bone and joint stress problems.
"Exercises such as free access to paddocks or ponying on firm, uniform surfaces reduce the chance for overexertion," he said. "Most frequently, the weanlings are worked at a trot." Freeman said all-encompassing recommendations about levels of exercise intensity for weanlings are difficult because of individual differences in how weanlings respond to exercise, as well as environmental differences in which the weanlings are being worked.
"Recommendations that can be made include allowing weanlings to warm up by slow work before pushing for faster speeds and allowing for sufficient "cooling down" by reducing intensity levels before returning to the stall or other housing areas," Freeman said. Harder surfaces will put more stress on bones, a positive aspect if it stimulates bone strength but a negative effect if too much concussion is produced for too long a period of time. Length of a single exercise bout may be more important than some managers realize, Freeman said. Breakdown of bone may be caused more by extending the length of a single workout than exercise intensity.
"It's advisable to split single workouts into 'two-a-days' to promote appetite and healthy growth," Freeman said. "Many experienced managers advocate short bouts of moderately intense exercise several times a day, rather than one long bout of less intense exercise, to stimulate healthy bone growth."