Lactate concentrations can now be measured rapidly and inexpensively in equine hospitals or in the field with a degree of accuracy that is acceptable when compared to laboratory analysers. Arterial or venous blood samples can be used. Short-term storage of samples for up to 4 h at room temperature does not appear to affect the result. Taking a sample in the field and returning to the practice to analyse it is therefore feasible.
Lactate measurement is useful in horses with colic to aid in the diagnosis of an ischaemic lesion and to determine the probability of a successful outcome if surgery is undertaken. Lactate concentrations are also useful as an indicator of hypoxia and/or circulatory disturbances associated with intra-, or post partum abnormalities including dystocia, prematurity, dysmaturity, neonatal encephalopathy, sepsis, systemic inflammatory response syndrome or enteritis. Measuring lactate concentrations may assist in determining the severity of these conditions and the need for intensive care. Initial lactate concentration and increases or decreases in blood lactate concentration following a period of treatment can provide useful prognostic information. Lactate may also be measured during training to monitor fitness and performance.