Changes

==Description==

==Description==

Equine Serum Hepatitis (ESH) is the most common cause of acute hepatitis in horses. It is often associated with prior administration of an equine biologic product, most commonly tetanus antitoxin. Encephalitis vaccines and equine serum have also been implicated as well as alkaloid toxicity and mycotoxins. Several cases have been reported occurring in groups of horses in which no biologic product had been administered, leading to the possibility of an infectious or viral aetiology.  A Type III (immune-complex mediated) hypersensitivity reaction also has been proposed.  

Equine Serum Hepatitis (ESH) is the most common cause of acute hepatitis in horses. It is often associated with prior administration of an equine biologic product, most commonly tetanus antitoxin (TAT). In some cases, the affected horse may not have received TAT but may have been in contact with another horse that received TAT. Other biologic products that have been implicated include encephalitis vaccines and equine serum. Other aetiologies such as alkaloid toxicity and mycotoxins have been reported. Several cases have been reported occurring in groups of horses in which no biologic product had been administered, leading to the possibility of an infectious or viral aetiology.  A Type III (immune-complex mediated) hypersensitivity reaction also has been proposed.  

==Signalment==

==Signalment==