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| | ==Diagnosis== | | ==Diagnosis== |
| − | In horses, a minor cross-match is performed using the foal's red blood cells and the mare's serum. A positive agglutination indicates a diagnosis of NI.
| + | To definitively diagnose the condition in horses, a minor cross-match is performed using the foal's red blood cells and the mare's serum. A positive agglutination indicates a diagnosis of NI. |
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| | ==Treatment== | | ==Treatment== |
| − | | + | Treatment in foals depends on rapid identification of sick foals and prevention of suckling the dam for 48-72 hours. If foals are less than 24 hours old at the time of diagnosis, it should be muzzled and fed supplemental milk. As the foal's intestine becomes impermeable to absorption of colostral antibodies by 24 hours of age, prevention of nursing until the foal is 30 hours of age should be sufficient. |
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| − | '''First pregnancy from a stallion with incompatible blood type to the mare:'''
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| − | Following mating of a mare and stallion with incompatible blood types, the neonate inherits the sire's blood type. At parturition, or because of placentitis, RBCs from the foal enter the maternal circulation. The surface of the foal's RBCs possess an antigen (usually Aa or Qa) that the mare's RBCs lack. The mare begins to mount an immune response towards the foal's RBCs. There are no antibodies against the foal's RBCs in the mare's colostrum as there has not been sufficient time to mount an immune attack and secrete them into the colostrum. The foal's intestine stops absorbing maternal antibodies after 30 hours (as previously discussed) and thus, when the alloantibody is secreted in the milk, it does not affect the foal.
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| − | '''Subsequent pregnancy from the same stallion or same blood group as previously exposed to'''
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| − | * Foal is born and suckles from the mare.
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| − | * Colostrum already contains alloantibodies against the foal's RBCs causing there to be RBC destruction or removal from the circulation [[Type II Hypersensitivity|(type II hypersensitivity reaction)]] leading to haemolytic anaemia and jaundice.
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| − | * When the foal's intestines are no longer able to absorb maternal antibody (approximately 30 hours post partum) it is safe to return the foal to the mare.
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| | ==Prevention== | | ==Prevention== |