Assessment of effect of reducing the number of tissue types in the bacteriological examination used in relation to meat inspection.

Bacteriological examination (BE) is used in several European countries as a supplement to the official meat inspection, if needed, to determine whether a macroscopic post-mortem finding represents a local or systemic condition at the time of slaughter, where the latter will lead to condemnation of carcass and organs. In Denmark, BE involves microbiological assessment of spleen and muscle tissues of slaughtered animals considered to have acute localised but not generalised infections, e.g., endocarditis or endophlebitis. Using BE results from 146 bovines, analysed between January 2022 and January 2024, we investigated what the judgement regarding meat inspection would be if just one tissue type was analysed. The official BE results led to acceptance of 83% of the carcasses, whereas 17% were totally condemned. The agreement between the judgement (condemn vs. accept) of muscle and spleen cultivation was high when measured as Gwet's first-order agreement coefficient (AC1 = 0.82). If only the spleen had been used for judgement, 15% would have been condemned, whereas if only the muscle had been used, 5% would have been condemned. Any bacteria detected in the spleen of these animals might reflect either local or generalised bacteriaemia, whereas bacteria detected in in the muscle might reflect generalised bacteriaemia. If muscle is chosen as the single tissue type for a BE, we recommend condemning the organs from bovines destined to BE, as some organs could contain bacteria in numbers above the accept limits. A strengths-weaknesses-opportunities-threats (SWOT) analysis revealed issues that can be used in simplifying the BE protocol to include only one tissue type. These results are of interest to all countries that apply BE for meat inspection.