A sandwich ELISA was developed for the detection of bovine meat and bone meal (BMBM) in feed, based on polyclonal rabbit antibodies raised against the synthetic N-terminal amino acid sequence 1-9 (YLDHWLGAP) of bovine osteocalcin. To set up a sandwich ELISA pair, a commercial mouse monoclonal capture antibody binding to a highly conserved epitope in the mid-fragment of the peptide was employed. It is shown that the bone marker osteocalcin is immunologically well detectable in BMBM extracts obtained by a simple EDTA based procedure even in a sample heated up to 145 oC. Furthermore a genus-specific restriction of the major specificity to cattle and horse was possible. The observed bi-specificity is consistent with theoretical predictions. The assay sensitivity with bovine osteocalcin of 1 ng was sufficient to enable the detection of 0.1% BMBM in compound plant feed or fish meal, for which no cross reaction was observed. In general the quantification of osteocalcin in extracts is possible using a standard curve procedure with pure bovine osteocalcin. the major specificity to cattle and horse was possible. The observed bi-specificity is 22 consistent with theoretical predictions. The assay sensitivity with bovine osteocalcin of 1 ng 23 was sufficient to enable the detection of 0.1% BMBM in compound plant feed or fish meal, for 24 which no cross reaction was observed. In general the quantification of osteocalcin in extracts 25 is possible using a standard curve procedure with pure bovine osteocalcin. 26