Polymerase chain reaction (PCR)-based molecular methods are gaining popularity in bacterial identification, but information on their performance with mastitic milk samples is limited.

In a recent study conducted by researchers in Finland and the Netherlands, the results of a PCR test kit were compared with those of conventional bacterial culture, based on 1,000 quarter milk samples from cows with clinical and subclinical mastitis, and from healthy cows.

They found that the PCR test was more sensitive and faster than conventional culture and holds promise as a tool to complement traditional methods in mastitis diagnostics.

The scientists suggest that further study is required to investigate how high sensitivity of PCR and its quantitative features can be applied to improve separation of relevant udder pathogens from likely contaminants in samples where multiple species are detected. Furthermore, increasing the number of species targeted by the PCR test would be advantageous.

The research was published in the December Journal of Dairy Science.