Enzyme activity in the serum of thoroughbred horses in the United Kingdom.

This paper records the concentrations of aspartate amino transferase (A.A.T.), creatine kinase (C.P.K.), sorbitol dehydrogenase (S.D.H.), alpha-hydroxybuturate dehydrogenase (alpha-H.B.D.) and alkaline phosphatase (A.P.) activity observed in the sera of Thoroughbred horses in the United Kingdom, at rest and during training. The methods of analysis have been selected to achieve the optimum precision when used for horse serum. During training A.A.T., C.P.K. and alpha-H.B.D. are related and demonstrate intermittent periods of increasing activity. S.D.H. remains unchanged but demonstrates increases associated with raised titres to equine rhinopneumonitis virus in the serum during the period in which the animal is clinically normal.