As a vet on a pig farm, it is important to know which strains of a particular species of bacteria are present. This is necessary in order to determine the correct strategy for controlling the bacteria. In pig production, this is important for the control of Streptococcus suis. An important question is whether the clinic in piglets is caused by the same strain or whether, on the contrary, there is a wide variety of Streptococcus suis strains. It is possible that they cause different clinical problems. A comparison can be made between strains found in different organs, or in the form of a historical survey. Validation studies carried out by GD prior to the implementation of this FTIR technique showed that there were pig farms where the collected Streptococcus suis isolates from one farm produced the same IR spectrum, whereas the Streptococcus suis isolates from other pig farms produced many different IR spectra per farm.

The only way to know how much variation there is in the strains of Streptococcus suis on a farm is to do regular testing. Finally, you can only be sure that there is only one type circulating on the farm if you have examined several clinical cases and compared the cultured isolates. It is difficult to say how often samples should be taken. It depends on so many individual farm factors. The basis is always to keep a historical record of which strains have been observed on a farm and what the clinical signs of animals with streptococcal infection have been.