Science Supports Slow, Steady Weaning of Foals

Ask 10 breeders how they wean foals and you may receive ten different responses! How a foal is weaned can greatly affect short- and long-term health, according to a new study*.

“In feral horse populations, foals aren’t weaned until they’re almost one year of age, when the mare is about to foal again. The process occurs slowly and the mare-foal bond remains intact,” explained Laura Petroski-Rose, B.V.M.S., a veterinarian for Kentucky Equine Research.

In many domestic equine operations, weaning occurs “abruptly and definitively” at approximately 4-6 months of age. In the current study, Lansade and colleagues pointed out, however, that abrupt weaning:

• Negatively impacts behavioral, neuronal, and hormonal responses in the foal;

• Induces stress, manifested as increased locomotion, vocalization, and stereotypies;

• Results in physiological responses, such as increased cortisol and catecholamine levels (stress hormone levels):

• Decreases immune system functioning, potentially putting foals at risk for infection or decreased response to vaccination; and

• Contributes to weight loss.

“Early weaning reportedly also has negative long-term effects caused by changes at the genetic level, called epigenetics, resulting in behavioral changes and personality modifications,” relayed Petroski-Rose.

The positive power of progressive weaning was supported by directly comparing two groups of foals: one that was weaned suddenly while the other was weaned progressively. The veterinary research team reported the following:

• Progressively weaned foals whinnied and trotted less, and had lower cortisol levels than foals weaned suddenly; and

• Progressively weaned foals became more curious, less fearful, and less gregarious than suddenly weaned foals, and those behaviors persisted for at least three months;

Petroski-Rose added, “The study also showed that progressive weaning was also beneficial and less stressful for the mare.”

“In conclusion, this study shows that progressive habituation to separation alleviates the negative effect of definitive weaning on both the mother and her young compared to sudden separation,” concluded the researchers.

Knowing that weaning is stressful and that stress influences essentially every body system, including the immune and nervous systems, supplement mares and foals with omega-3 fatty acids. Offering this type of product during gestation and nursing and then continuing to supplement both the mare and foal separately will support brain development in the foal, as well as the immune system. Kentucky Equine Research offers EO-3, a palatable marine-derived source of omega-3 fatty acids, containing 6,750 mg of EPA and DHA in a single serving.

*Lansade, L., A. Foury, F. Reigner, et al. 2018. Progressive habituation to separation alleviates the negative effects of weaning in the mother and foal. Psychoneuroendocrinology. 97:59-68.