Those concerned about Involuntary Hippophagia: (the unintended ingestion of a horse, or part thereof ) may take comfort in a report published in the journal Meat Science, Volume 70, Issue 4, 2005.
As far back as eight years ago, farsighted government researchers at (what was) the Central Science Laboratory, Yorkshire, UK, (now swallowed by the Department for Environment, Food and Rural Affairs), had already developed an exquisitely sensitive Horse and Donkey test using real-time PCR. The new assay methods, which were validated against samples of horse sausage, horse steak, horse burger and horse salami, (and corresponding donkey foodstuffs) were so accurate that they could detect just a few picograms of horse or donkey in a sample (1 pg is roughly the weight of a single E. coli bacterium).
“We have developed real-time PCR assays specific for horse and donkey, applicable to the detection of low levels of horse or donkey meat in commercial products. Primers, designed to the mitochondrial cytochrome b gene, were 3′ mismatched to closely related and other commercial species. Amplification of non-target species DNA was prevented by truncation of primers at the 5′ position, thereby conferring complete specificity. Both assays were highly sensitive and detected the presence of 1 pg of donkey template DNA or 25 pg of horse template DNA when assessed using dilutions of DNA in water. Model food samples, spiked with horse or donkey muscle and commercial products containing horse, were successfully tested for the presence of horse or donkey, demonstrating the applicability of the assays to food products.“