Detection of rendered meat and bone meals by PCR is dependent on animal species of origin and DNA extraction method.
The capability of eight commercially available DNA extraction kits to extract bovine DNA originating in meat and bone meal from fortified feed was evaluated. Four different batches of bovine meat and bone meal (BMBM) were used for DNA extraction with the eight commercial DNA extraction kits. Within each kit, there were minimal differences in the batch-to-batch amounts of extracted DNA. There were differences between the kits in the amounts of DNA that could be extracted from the same amount of starting BMBM. These differences did not translate into differences in the amount of amplifiable DNA from BMBM-fortified dairy feed. Using a validated real-time PCR method, the kit yielding the highest amount extractable DNA was completely unable to yield a positive PCR result; one other kit was also unable to produce a positive PCR result from DNA extracted from BMBM-fortified feed. There was a complete lack of a correlation between the amount of bovine DNA isolated from BMBM by a given extraction kit compared with the relative amounts of DNA isolated from fortified animal feed as evidenced by the cycle threshold values generated using the real-time PCR method. These results demonstrate that extraction of DNA from processed animal protein is different for pure ingredients and fortified animal feeds. These results indicate that a method specifically developed using just animal-derived meat and bone meal may not yield a functional assay when used to detect animal tissues in complete animal feed.
Myers
Michael J
MJ
U.S. Food and Drug Administration, Center for Veterinary Medicine, Office of Research, 8401 Muirkirk Road, Laurel, Maryland 20708, USA. michael.myers@fda.hhs.gov
Farrell
Dorothy E
DE
Deaver
Christine M
CM
Mason
Jacquline
J
Swaim
Heidi L
HL
Yancy
Haile F
HF
D000821:Animal Feed / Q000032:analysis*; D000818:Animals; D001688:Biological Products / Q000032:analysis; D002417:Cattle; D004247:DNA / Q000302:isolation & purification*; D016643:Encephalopathy, Bovine Spongiform / Q000517:prevention & control / Q000635:transmission; D005506:Food Contamination / Q000032:analysis*; D005784:Gene Amplification; D008903:Minerals / Q000032:analysis*; D016133:Polymerase Chain Reaction; D012680:Sensitivity and Specificity; D012756:Sheep; D013045:Species Specificity
D001688:Biological Products; D008903:Minerals; D004247:DNA; C027762:bone meal