UTERINE DILATION IN THE MARE.

This research focuses on understanding the history of horse blood groups, particularly with regard to a condition known as hemolytic disease or neonatal isoerythrolysis that results from transplacental isoimmunization.

History of Horse Blood Groups

• The study discusses how the historical understanding of horse blood groups can be divided into two phases based on a pivotal discovery about hemolytic disease (neonatal isoerythrolysis).
• The first phase began after the human blood groups were classified into A, B, AB and O, when researchers attempted to apply similar classifications to horses.
• Research during this era found naturally occurring isoagglutinins, which are antibodies that cause foreign red blood cells to clump together or agglutinate.
• Despite these findings, there was no strict reciprocal relationship between these agglutinins in the blood serum and the agglutinogens (antibodies eliciting elements) on the red blood cells.
• This era was marked by inconsistencies in most studies and a failure of different investigators to compare their typing fluids.

Transplacental Isoimmunization

• Transplacental isoimmunization refers to a condition where the mother’s immune system produces antibodies that attack the red blood cells of the developing foetus or newborn. This is a common cause of hemolytic disease in horses and mules.
• The research detects a crucial transition in understanding horse blood groups following the discovery that neonatal isoerythrolysis in horses and mules could occur due to transplacental isoimmunization.

Current Understanding and Directions

• The second phase of study in the history of horse blood groups was prompted by the understanding of red blood cell antigens’ role in hemolytic disease.
• The report therefore indicates an evolution toward better understanding and treatment of this impactful condition in equine subjects.