Haemolytic disease of the newborn foal.

This research article reviews the clinical characteristics of the condition known as haemolytic disease of the newborn foal (HDNF). It also discusses the current understanding of the serological factors related to the isoimmunisation of mares and evaluates available methods for identifying potential “haemolytic mares”. Moreover, the article explores the advances in treatment for severely affected foals, observing that a straightforward transfusion of mare’s packed erythrocytes has shown increased effectiveness compared to previous exchange transfusion methods.

Overview of haemolytic Disease of the Newborn Foal (HDNF)

• The research starts off by reviewing the clinical features of the haemolytic disease of the newborn foal, abbreviated as HDNF. This disease is an immune-mediated disorder in newborn horses defined by premature destruction of red blood cells and can result in severe jaundice and anemia.

Serological factors and isoimmunisation of mares

• The article examines the known serological factors associated with isoimmunisation of mares. Serological factors pertain to properties in the blood that can give insights into the body’s immune response. Isoimmunisation refers to the production of antibodies in the mare that target the foal’s red blood cells if they inherited specific antigens, usually from the stallion, not present in the mare’s blood.

Screening of ‘haemolytic mares’

• The article goes on to evaluate the existing methods for screening mares that have the potential to become ‘haemolytic’. This essentially means identifying those mares that could potentially be isoimmunised and thus, pose a risk to their newborn foals due to the destruction of the foal’s red blood cells triggered by the mare’s antibodies.

Advances in treatment for severly affected foals

• In the final part of the article, different treatment methods for severely affected foals are scrutinised. While exchange transfusion – the replacement of the foal’s blood with blood from a compatible donor – has commonly been used, the article reports that a simpler transfusion method involving mare’s packed erythrocytes has shown better results. Packed erythrocytes refer to a blood product where most of the plasma, white blood cells and platelets are removed, leaving a concentrated solution of the mare’s red blood cells to be transfused into the foal.