Implications
(i) Biosafety
(ii) In vivo toxicity
(iii) Metabolization
Focus
(i) Safety
(ii) Oxidative stress and related parameters
(iii) Detection and quantification of substances and metabolites in body fluids, tissues and faeces
Models
(i) Experimental animals (rats, mice, pigs)
Why testing safety in vivo?
In vitro screening of cytotoxic properties of the test substance/extract/phytopreparation can only partially substitute in vivo tests. On the level of whole organism, many factors influence biological activity of substance/extract/phytoparation, e.g. bioavailability, excretion and metabolism.
Assessment of safety (biological activity)
Tests:
(i) Health status monitoring. growth curves, feed consumption
(ii) Macroscopic evaluation and histopathological examination of organs
(iii) Parameters of clinical biochemistry and hematology
(iv) Oxidative stres related parameteres
(v) DNA damage – single – stranded DNA breaks – Comet assay in peripheral lymphocytes, 32P-postlabeling of liver microsomal DNA adducts
(vi) Content of cytochrome P450 in liver microsomes
(vii) Detection and quantification of substances and metabolites in body fluids, tissues and faeces
Aim: To assess if the test substance/extract/phytopreparation will display effects on experimental animals.
Procedure: Experimental animals will receive the test substance/extract/phytopreparation as a feed additive. At the end of the feeding experiment, blood samples will be taken under anesthesia, organs of interest will be macroscopically evaluated and used for further examinations using the methods mentioned above.