I have been in the pet food industry, in some capacity, for my entire working life. Today, I learned about a set of FDA Guidelines that are written to help to keep our dogs (and us) safe. Until recently, I had no idea that these even existed. Apparently, I am not alone. A recent study, conducted by a team of researchers at North Carolina State University, asked over 400 dog owners about these guidelines; less than 5 percent knew about them (1).
Bugs in the Bowl
This obscure FDA document has to do with our dogs’ food bowls and how clean (or not) they are. The FDA created it because of evidence showing that pet food dishes are a common source of microbial contamination in pet-owning homes. Here are a few statistics:
- Overall contamination: A 2006 study reported that out of 32 different household surfaces, pet food dishes were ranked ninth highest for level of contamination (2). Resistant strains of medically important microbes (i.e. MRSA, MSSA) were found in up to one-third of the dishes. A subsequent study rated pet water bowls as third-highest in bacteria counts out of 26 different household surfaces (3). Yikes.
- Clostridium difficile: C diff, a dangerous and highly resistant pathogen that can cause severe illness, was found frequently in dog food dishes – this source ranked higher than, unbelievably, toilets (4)
- Dog toys: Although not studied extensively, pet toy surfaces also have been reported to have high levels of contamination with aerobic bacterial species – again with higher counts than many other household items (2).
Food Prep Practices?
The FDA Tips is a set of “best practices” for pet feeding and food dish hygiene. These are pretty straightforward and not unlike recommendations for our own food and utensils – Wash food bowls and utensils thoroughly after meals, wash your hands, properly handle and store pet foods.
However, the question is, do pet owners regularly do these things? And, if they do, do these practices actually reduce food-borne microbial contamination of our dogs’ food and water bowls?
Let’s Ask Science
The researchers surveyed a group of 417 dog owners regarding their daily feeding and pet bowl hygiene practices. A sub-group of 68 owners provided food dish swabs for microbial plate count (MPC) analysis. Owners were randomly assigned to one of three groups: A (provided with the FDA pet food hygiene guidelines); B (provided with both the FDA pet and human food hygiene guidelines; and C (no guidelines provided). Swabs were collected at the start of the study and again one week later.
As mentioned earlier, less than 5 percent of owners were aware that FDA guidelines for pet bowl hygiene even existed. The survey data also revealed this:
- Two-thirds of respondents (66 percent) said that they do not regularly wash their hands after feeding their dog.
- On-third of the owners (33 percent) stated that they prepared their dog food on human food preparation areas in their kitchen.
- And, almost half (43 percent) stored their dog’s food in a location that was five feet or less away from human food.
Food Bowl Microbes: When actual microbial levels in food bowls were measured, the bowls of Groups A and B, who had received FDA guidelines, showed dramatic reductions in contamination levels when compared with Group C, owners who received no instruction.
Best Practices: When hot water was used to clean dog bowls, numbers decreased most; cold water was not as effective (not surprising).
This IS surprising: After learning about the reduction in microbial contamination of their dogs’ food bowls after they began to regularly wash them, owners were subsequently asked if they would continue to adhere to their new hygiene practices. Only 20 percent reported that they were likely to continue these practices…… 80 percent were apparently unconvinced.
Take Away for Dog Folks
Okay. True confession time. While Mike and I do wash our dogs’ (and Pete the cat’s) food bowls, we generally had not been doing this after every meal or even every day. We use stainless steel bowls and we also have dogs who completely devour their food and lick every bowl clean. We washed their bowls, hot water, soap, the entire deal, a few times a week.
This study and the levels of contamination that were reported provide a strong incentive for us to do better. We are now trying to build a habit of washing our dogs’ bowls after each meal. Washing hands was already pretty well-established (but certainly we can always improve). Because we feed human grade foods, I am not particularly worried about where I store food or food prep surfaces. We clean these the same way that we clean our own food surfaces and utensils.
So, Science Dog readers – What are your dog food preparation and bowl hygiene habits? Did this study make you reconsider any of your practices?
Freshly Washed Dog and Cat Food Bowls at the Cases
- Luisana E, Saker K, Jaykus L-A, Getty C. Survey evaluation of dog owners’ feeding practices and dog bowls’ hygiene assessment in domestic settings. PLos ONE 2022;17(4):e0259478.
- Scott E, Duty S, McCue K. A critical evaluation of methicillin-resistant Staphylococcus aureus and other bacteria of medical interest on commonly touched household surfaces in relation to household demographics. American Journal of Infection Control 2009; 37:447-453.
- Donofrio R, Bechanko R, Hitt N, et al. Are we aware of microbial hotspots in our household? Journal of Environmental Health 2012; 75:12-19.
- Weese J, Finley R, Reid-Smith R. et al. Evaluation of Clostridium difficile in dogs and the household environment. Epidemiology and Infection 2010; 138:100-104.