The study, which analyzed 35 RMBDs from eight brands, revealed that E. coli 0157 was isolated from eight products (23 percent), Salmonella species in seven products (20 percent), and Listeria species were present in 15 products (43 percent). Four products (11 percent) found the parasite Sarcocystis cruzi; another four contained Sarcocystis tenella. Two products (6 percent) revealed Toxoplasma gondii.
Researchers also found evidence the raw meat harbored antibiotic-resistant bacteria.
“Despite the relatively low sample size of frozen products in our study, it is clear that commercial RMBDs may be contaminated with a variety of zoonotic bacterial and parasitic pathogens that may be a possible source of bacterial infections in pet animals and if transmitted pose a risk for human beings,” they added.
Pets fed RMBDs can pass pathogens to humans through direct contact, such as licking or brushing up against them, according to scientists. Researchers wrote that pathogens also can be transferred through direct contact with the food, through contact with household surfaces, or by ingesting cross-contaminated human food.
RMBDs include raw dried dog and cat treats such as pig ears, home-prepared meats based from food sold for human consumption and commercial raw meats marketed for pets. Researchers believe there is no evidence for any benefit of RMBDs compared to mainstream dry or canned pet foods and that raw meat-based diets may even be less nutritious.
“In nutritional terms, these diets are often deficient in several nutrients and may therefore lead to serious health problems, especially in young animals that are growing,” according to the Utrecht study.
Because of the increased likelihood of pets fed RMBDs becoming infected with antibiotic-resistant bacteria than animals on conventional diets, researchers issue dire warnings.
“The presence of antibiotic-resistant bacteria in RMBDs could therefore pose a serious risk to both animal health and public health—not only because infections with these bacteria are difficult to treat, but also because of the potential of it contributing to a more widespread occurrence of such bacteria,” researchers said.
“It is important to encourage awareness of the possible risks associated with feeding raw meat-based diets to companion animals, and pet owners should be educated about personal hygiene and proper handling of raw meat-based diets,” the study said, adding that education from veterinarians is a vital component.