[Neonatal isoerythrolysis in newborn foals].

This research article provides a comprehensive analysis of neonatal isoerythrolysis in newborn foals, explaining the cause, symptoms, diagnosis, prevention and treatment strategies of the disease.

Cause and Pathogenesis

• Neonatal isoerythrolysis in foals is triggered by isoimmunization of a brood mare to the Aa and Qa erythrocyte antigens of her foal.
• It can occur when the mare lacks Aa or Qa blood group antigens and is sensitized to these antigens, possibly through pregnancy, parturition, blood or plasma transfusions.
• The mare then passes on antibodies to her foal through colostrum (the first form of milk produced by a mammal after childbirth), which are harmful to the foal’s own blood cells.
• These antibodies result in haemagglutination (clumping of the foal’s red blood cells) and haemolysis (destruction of red blood cells), which lead to a reduction in the count of erythrocytes (red blood cells), packed cell volume (PCV), and haemoglobin in the foal.

Clinical Symptoms and Diagnosis

• The clinical symptoms derived from these conditions usually appear between the second and third day of the foal’s life, typically within 8 to 96 hours.
• The diagnosis of the disease is made through a clinical examination and by determining the erythrocyte count, PCV and haemoglobin concentration.
• Immunological tests can also help to confirm the presence of the disease.

Prevention and Treatment Strategies

• Different tests can be utilized to prevent neonatal isoerythrolysis.
• Before childbirth, brood mares can be examined for blood groups and checked for antibodies to Aa and Qa, to recognize mares at risk of causing neonatal isoerythrolysis in their foals.
• After the foal’s birth, the compatibility of the mare’s colostrum and the foal’s erythrocytes can be verified by the “jaundice foal agglutination” test.
• The researchers also provide instructions for prophylaxis of neonatal isoerythrolysis and for treatment via red blood cell or whole blood transfusions.