What causes neonatal Isoerythrolysis?

What causes neonatal Isoerythrolysis?

Neonatal isoerythrolysis is caused by isoimmunisation of a brood mare to the Aa and Qa erythrocyte antigens of the foal. The disease can develop, when the mare does not possess Aa resp. Qa blood group antigens, is sensitized to the Aa or Qa erythrocyte antigens–i.e. through pregnancy, parturition, blood resp.

Why the blood group incompatibility between mare and foal does not occur in utero?

If a foal inherits from its sire a red cell factor (antigen) that the mare lacks, the mare may develop antibodies to that antigen. There is no harm to the foal in utero, as there is no comingling of the mare’s blood with that of the fetus.

Why do foals suffering from neonatal Isoerythrolysis have yellow gums?

The condition occurs when a foal ingests colostrum containing antibodies directed against its red blood cells (RBC’s). Destruction of RBC’s leads to release of a pigment called bilirubin that may cause the gums, white parts of the eye and feces to become yellow or jaundiced.

What does it mean when a horse has neonatal isoerythrolysis?

Neonatal isoerythrolysis (NI): This mouthful of a term literally means the destruction of a newborn foal’s red blood cells. The debilitating condition, in which a mare’s antibodies attack her foal’s red blood cells, can be lethal for a foal due to the resulting liver damage and other problems.

When do mule foals show signs of isoerythrolysis?

The incidence may be as high as 10% in mule foals, with antibodies directed against donkey factor, a red blood cell factor unique to mules. 215 Foals are usually healthy at birth, with clinical signs developing 12 to 36 hours after ingestion of colostrum.

What kind of hemolytic disorder does a foal have?

Neonatal isoerythrolysis (N.I.) is an immune-mediated hemolytic disorder of newborn foals due to absorption of colostral immunoglobulins which contain antibodies against red cell antigens inherited from the stallion.

How are red blood cells destroyed in neonatal isoerythrolysis?

Neonatal isoerythrolysis is characterized by the destruction of red blood cells in the circulation of a foal by alloantibodies of the mother absorbed by the foal from the mare’s colostrum.