Immunoassay testing for barbiturates using alternative matrices in postmortem tissues from cats and dogs.

This article focuses on evaluating the use of a human immunochromatographic assay, originally designed for urine, to detect barbiturate drugs—specifically pentobarbital—in alternative postmortem tissues from dogs and cats during veterinary forensic autopsies. The study compared two tissue preparation methods, sonication and bead homogenization, across multiple matrices including heart, liver, spleen, skeletal muscle, blood, and urine, finding that sonication yielded 100% concordance with reported euthanasia status and gas chromatography–mass spectrometry (GC–MS) confirmation, while bead homogenization showed slightly lower concordance due to some invalid results. The findings support the use of various alternative tissues for barbiturate screening when urine is unavailable, highlighting the assay’s utility as a rapid, cost-effective preliminary test in veterinary forensic investigations, with confirmatory GC–MS or liquid chromatography–mass spectrometry recommended for positive results.