Antigen capture ELISA using a monoclonal antibody for the detection of Mycoplasma bovis in milk.

An enzyme-linked immunosorbent assay (ELISA) using a monoclonal antibody (mAb) was developed to detect Mycoplasma (M.) bovis in milk samples from cattle. With this procedure, 1 x 10(5) colony forming units per ml (cfu/ml) milk were routinely detectable. No cross-reactions to other bovine mycoplasma species were observed. Both the sensitivity of 80.6% and the specificity of 94.9% are sufficient for its use in diagnosis of clinical mastitis. The sensitivity could be increased by 10% after introduction of 48-hour pre-incubation of samples. This allowed recognition of cows shedding M. bovis amounts of 10(3) cfu/ml in their milk, which is typical for subclinical cases. Screening of milk samples by means of this antigen capture ELISA has advantages over culture methods in terms of speed and potential to monitor large herds, thereby permitting early culling of infected animals to reduce transmission of the pathogen to non-infected animals.