Practical Application of DNA Fingerprinting To Trace Beef

Abstract

DNA fingerprinting allows the verification of conventional methods used to implement beef traceability. At any point along the supply chain, the identity of an animal or piece of meat can be checked by comparison of its DNA profile with an initial sample. Practical application of DNA fingerprinting to trace beef requires a choice of DNA markers as well as the optimization of sampling methods. This has been achieved as the result of collaboration between meat technicians and geneticists over a period of 4 years. The discrimination power of nine highly polymorphic microsatellite markers was evaluated. We propose that three markers (with a 0.001 probability that two individual profiles match by chance) are adequate for routine tests. Two key points along the production-commercialization chain where sampling must be systematic were defined: (i) the tagging of the calf (identity control) and (ii) after slaughter (slaughter control), before the animal loses its external appearance. The identity control was blood collected on a filter paper adapted to the ear tag; the slaughter control was the tagged ear itself. These constituted the control samples, which were archived with a code matching the individual tag number. Test samples were obtained on a random basis from live animals, carcasses, and pieces of meat at cutting halls and at the retail outlet and in cases when the verification of identity was needed. The DNA profiles of the test samples and the controls were then obtained and compared, to verify either an individual identity or the origin of a piece of meat from the stated animal.

Molecular traceability of beef from synthetic Mexican bovine breeds

“…These results were similar to those reported by other authors for Spanish (Vázquez et al, 2004) and Italian breeds (Orru et al, 2006;Dalvit et al, 2008a,b). As expected, MP diminishes with an increasing number of markers, down to R. Rodríguez-Ramírez et al…”

“…Other authors also reported very low values for the marker BM1824 (PIC = 55.9) in cattle from the pure Italian breed Chianina (Orru et al, 2006). On the other hand, BM1824 was not the least polymorphic when it was evaluated in beef from the Pirenaica breed (Arana et al, 2002) and Asturiana de los Valles and Asturiana de la Montaña breeds (Vázquez et al, 2004).…”

“…To guarantee both quality and safety, it must be possible to follow the path of a specified piece of meat back to any point in the supply chain (Vázquez et al, 2004). The meat industry has responded globally to a series of crises such as bovine spongiform encephalopathy, labeling scandals and outbreaks of enterohemorrhagic Escherichia coli infections.…”

“…These regulations seek to guarantee a traceability system that ensures a link between the carcass, quarters or pieces of beef and the individual animal or the group of animals from which they are derived. Therefore, traceability is achieved by making use of identification labels attached to live animals and meat products throughout the productioncommercialization chain (Vázquez et al, 2004).…”

Allele frequencies of microsatellite loci for genetic characterization of a Sicilian bovine population

“…Microsatellite markers represent the gold standard for unequivocal determination of the genetic identity and/or parentage, even with limited sample quantities (Taberlet et al, 1996) or when DNA is degraded. They can also be used to trace the meat through the production chain (Vázquez et al, 2004), to study genetic diversity in cattle (Radko et al, 2005), and to select animals in breeding programs. Currently, more than 1000 microsatellite markers have been evaluated for cattle (e.g., Barendse et al, 1994;Kappes et al, 1997).…”