PCR was applied for the discovery of adulteration of crude and processed beef meat with horse and donkey tissue. This was performed by blending (w/w) horse or donkey meat to beef meat in an extent up to 1:10000 (0.01%). The sensitivity was resolved as high as 0.01%. All used primers showed specificity in the PCR reactions utilizing layout DNAs from three animal species. PCR application on 96 beef meat and meat product samples gathered randomly from street vendors and prominent retail markets (24 of burger, 16 of minced meat, 24 of kofta, 16 of sausage, 7 of raw meat and 9 of launcheon) uncovered 6 positive for donkey tissue (3 from sausage, 2 from minced meat and 1 from kofta) and 2 positive for horse tissue (from sausage). This basic PCR strategy effectively distinguished adulteration of raw and processed beef meat samples with horse and donkey tissue. This work also highlights on the severity of the meat adulteration problem in Egypt.

A very limited research work concerning foods of porcine origin in Egypt were obtained in spite of presence of a considerable swine population and consumers. This study was conducted to investigate the prevalence of food poisoning bacteria isolated from local and imported retail pork by-products in Egyptian markets. A total of 80 pork samples, including 60 local pork by-products and 20 imported ones were used. The isolated bacteria species after biochemical and serological typing were Escherichia coli (59) and distributed as E. coli O157(27), E. coli O146(18) and E. coli O111 (14) by 33.75, 22.5 and 17.5%, respectively followed by Staphylococcus aureus which was isolated from 23 (28.75%), Salmonella spp. was represented by Salmonella typhimurium (9) Salmonella enteritidis (7) and Salmonella agona (4), as 11.25,8.75, and 5%, respectively. Finally, Listeria monocytogenes was isolated from 9 samples as 11.25%. The bacterial isolates were sensitive to ciprofloxacin and more resistant to penicillin, gentamicin, amoxicillin and ceftazidime. The bacterial isolation is considerably more in the local pork by-products than the imported samples. On the whole, both types are commonly in permissible limits of the Egyptian food quality standard as the high A.P.C. were Staphylococci and E. coli followed by Salmonella spp., then L. monocytogenes. To the best of our knowledge, this is the first report on isolation and identification of food born bacteria from pork by-products in Egypt.

Materials and methods Meat samplesRaw meat samples from 11 different animal species were collected randomly from Giza Governorate's butcher shops, common retail markets, veterinary faculties, Zoo and hospitals.