In vitro efficacy

Depending on the intended effect of the feed additive, the efficacy can be demonstrated e.g. from the acidification of the feed (acidity regulators), the inhibition of the growth of spoilage microorganisms (preservatives), or pathogens (hygiene condition enhancers) in the feed matrix. The studies should be designed to demonstrate the efficacy of the recommended level of the additive by targeting sensitive parameters in comparison to a control group. The study should cover a representative range of materials depending on the intended use of the additive (feed materials, complete or complementary feed, or water). The efficacy should be shown in at least three studies.

The experimental design should consider a sufficient number of observations to allow an adequate statistical analysis with a 95% confidence level, preferably utilizing parametric tests.

If not already known, an appropriate recommended level can be studied by screening various doses in the same feed matrix, and different measurement time points can be used to understand the kinetics of the effects.

Biosafe has strong know-how in designing these studies and selecting suitable test conditions to enable the analysis of a single strain or combinations of multiple feed additive strains.

In case standardised methods are not suitable, especially for a combination of multiple strains, analysis methods utilising a tailor-made growth medium can be developed. The discrimination ability of the growth medium can be confirmed with pulsed-field gel electrophoresis.