Clostridium novyi type B as a causative agent of bovine meat spoilage

A series of bovine meat spoilage cases in which meat from clinically healthy Belgian Blue cattle showed green discoloration are described. Histology of skeletal muscle revealed numerous spore-forming rods in the discolored areas of the meat. These organisms stained positively for Clostridium novyi by immunohistochemistry. A combination of 16S rDNA and fliC gene sequencing of bacterial DNA, isolated from the spoiled meat samples, revealed the unique presence of C. novyi type B. Although this bacterium has been implicated in clinical necrotic hepatitis in cattle, the cases described here are the first implicating C. novyi type B as a cause of bovine meat spoilage. ► Oxymyoglobin gives meat the bright red color. ► Sulfmyoglobin production gives meat a green color. ► When myoglobin is converted to sulfmyoglobin by anaerobic bacteria hydrogen sulfide is produced. ► Clostridium novyi can produce H2S since it carries the sulfite reductase gene.