title: A comparison of vitamin B12 levels in the livers and sera of sheep measured by microbiological and radioassay methods.
mesh_terms: D000818:Animals; D001681:Biological Assay; D003037:Cobalt Radioisotopes; D005260:Female; D007778:Lactobacillus / Q000378:metabolism; D008099:Liver / Q000032:analysis*; D008297:Male; D012756:Sheep / Q000378:metabolism*; D014805:Vitamin B 12 / Q000032:analysis* / Q000097:blood
chemical_list: D003037:Cobalt Radioisotopes; D014805:Vitamin B 12