The research article discusses the factors and considerations in managing weight loss in underweight adult and senior horses, which can be due to insufficient energy supply, increased energy expenditure, or underlying clinical diseases.

Insufficient Energy Supply

• The supply of energy could be reduced due to inadequacy of feed provided, not eating enough, diminished digestion and absorption, or an interruption in the metabolic process. Horses require feed that contains sufficient energy to ensure their health. If the feed lacks the necessary nutrients or if the quantity is not enough, it could lead to the horse being underweight.
• Another factor could be the horse’s ability to consume and digest the food. The provided diet might be sufficient, but if the horse is unable to eat or digest it properly, it can result in weight loss. This could be due to dental issues, digestive disorders, or other underlying health concerns.
• Disruptions in the horse’s metabolism, such as hormonal imbalances or diseases, can also alter how their body processes the nutrients from their food. Consequently, they could end up not getting enough energy from their meals.

Increased Energy Expenditure

• Activities such as exercise or external factors like cold temperatures can result in increased energy use in a horse’s body. This increased energy demand means the horse needs more food energy to replace what is used, which if not met, results in weight loss.
• Pregnant and lactating mares have higher energy demands, due to the energy needed for the growth of the foal and milk production. An inadequate dietary intake during these times can lead to significant weight decrease.

Underlying Clinical Diseases

• Chronic diseases such as inflammation, neoplasia (abnormal tissue growth), and conditions that lead to protein loss may lead to, or intensify existing, weight loss. These conditions may interfere with the horse’s ability to process nutrients efficiently, or increase energy expenditure, further destabilizing the balance of energy supply and demand.

Importance of a Methodical Approach

• Because the reasons for weight loss in horses can be multifaceted, a systematic approach to investigating and treating weight loss is necessary. This process includes assessing the horse’s diet, evaluating its health status, and adjusting feeding and care practices as needed to ensure the horse gets adequate energy and remains at a healthy weight.