VHLGenetics constantly works on the extension of the test-portfolio, assisting our clients in achieving their breeding goals. In pigs, we had added the PRRS-tests to our portfolio 4 years ago, although these tests have been indirect tests, which we only offer in exceptional cases. As a rule, we aim to offer only direct tests for disease- or trait-causing genetic variants. At the point of time of launching these PRRS-tests we have been convinced that these resistance tests will help pig breeders in their battle against this deleterious infectious disease.
Besides the continuous work on the extension of our test-portfolio, we also work constantly on the re-evaluation of the tests and the respective results. Our goal is staying up-to-date with our analytical programme on one hand and offering reliable tests with highly significant results on the other hand. This continuous process leads us also to the finding of new correlations of variants to traits in particular breeds, which have not been reported before.
An evaluation study with one of our largest pig-clients lead to the finding that the results of the PRRS-resistance-tests showed only a weak correlation with the resistance against the PRRS-virus in production populations.
With these facts in hands 1) indirect test, 2) only weak correlations in production populations, i.e. only a minor help for pig breeders, we decided not to offer the PRRS-tests PRRS1, PRRS3, PRRS4 in our test-programme anymore. This decision does not affect the correctness of former test results or show that the results for the PRRS-tests have been insignificant. The finding in our collaborative research project indicates only that the correlation of these indirect markers to the resistance against the PRRS-virus is not strong enough to found a breeding scheme on the test-results.