Cold housing effects on growth and nutrient demand of young horses.

The research study examines the impact of cold housing conditions on the growth and nutritional needs of young horses. The findings highlight the differences in growth rates, digestion, and energy requirements between horses kept in warm and cold environments.

Research Methodology

• The research involved 12, 7-month-old Standardbred colts, which were observed over a period of 22 weeks starting in late November.
• The colts were divided into two groups: one group was housed in a barn kept at 10 degrees Celsius (warm condition), while the other group was kept in a barn without external heat (cold condition).
• All horses were allowed outdoors for 4 hours daily.
• The horses’ hair coat weight, weight gain, skeletal growth, nutrient digestion, and energy requirement were measured and compared between the two groups.

Research Findings

• The average temperatures of the warm and cold barns from November to April were 10.9 degrees Celsius and -5.2 degrees Celsius, respectively.
• The hair coat weight of the cold-housed colts was 1.4 to 2 times higher than the warm-housed colts from December through April. The hair coat weight of both groups, however, declined from fall to spring.
• The warm-housed colts gained weight 29% faster than the colts housed in cold conditions. The rates were 0.67 kg/day and 0.52 kg/day, respectively.
• The housing temperature had no significant impact on skeletal growth, as measured by cannon bone circumference, wither, and croup height.
• Regarding nutrient digestion, the study compared the two groups of colts with mature, warm-housed ponies. Ponies displayed longer digestive tract retention times and higher digestibilities for every nutrient than the young horses.
• Furthermore, cold-housed colts digested more Acid Detergent Fiber (ADF) and less phosphorus than warm-housed colts.
• The digestibility of Dry Matter (DM), Neutral Detergent Fiber (NDF), and phosphorus declined over time for colts but not for ponies.
• The energy requirement for maintenance was estimated at 34.6 kcal/kg body weight for colts in cold conditions and 26.3 kcal/kg body weight for those in warm conditions.
• The research concluded that young horses require 1.3% more energy for maintenance per Celsius degree decrease in temperature below 0 degrees Celsius.
• To maintain a constant moderate weight gain, the daily intake of Digestible Energy (DE) needs to be increased by 0.7% per Celsius degree decrease in ambient temperature below 0 degrees Celsius.