Probably one of the major concerns most dog owners have with transitioning their dog to raw dog food is the potential contamination of things like salmonella, listeria and e coli.
Critics of raw dog food often state that raw food has a higher chance of pathogen contamination than commercially available cooked foods – including freshly cooked, kibble and canned. Most majory veterinary medical associations within the USA have released statements against feeding raw foods, including the AVMA, Tufts Veterinary Nutritionist, and AHAA.
“The AVMA discourages the feeding to cats and dogs of any animal-source protein that has not first been subjected to a process to eliminate pathogens because of the risk of illness to cats and dogs as well as humans.”AVMA Raw Dog Food Statement
Proponents of raw dog food often cite that pathogen risk is very small, that proper handling, ingredient sourcing, manufacturing practices, and storage can greatly mitigate any risk. They also argue that dogs due to their shorter digestive tracts are not able to get infections as easily as people and that wolves eat raw meat without issue. Finally most they haven’t heard of anyone getting sick due to feeding their dog raw food.
So let’s look at the research we have pertaining to Salmonella in Dog Food, and you can decide if raw carries significant risk, or not in comparison to other forms of feeding dogs.
Is Raw Dog Food More Likely to be Contaminated With Salmonella Than Kibble?
By just looking at the FDA recalls for pet food we can see that Salmonella has been recalled in both kibbled and dry dog foods. Interestingly – pet food has not been recalled (as of yet) in canned foods or within freshly cooked products.
It is important to note that there is contamination for Salmonella within the human food system as well. Supermarket raw chicken for example is allowed to contain Salmonella at a certain rate (as specified by the USDA & FDA) – with the specification that all packages have to be labeled that meats must be cooked prior to consumption. And if we look at FDA recalls in produce – we do have one recall with potential Salmonella contamination in onions between 2017 to 2020.
If we compare recalls of kibble and raw for the same period we see that raw pet foods have had 12 recalls of products due to Salmonella, and kibbled products have had 1 recall due to Salmonella. There were no recalls due to Salmonella in canned or freshly cooked dog foods during this period.
Even though there are more recalls for raw foods for this time period than kibble or cooked dog foods – this is not really the most accurate way to compare the incidence of Salmonella within dog foods. The reason for this is that the FDA does not routinely test dog foods, dog food recalls are largely self-reported, and pathogen testing is not required prior to releasing a dog food to the public. Thus it is highly possible that there is more contamination of dog foods than in the FDA report.
Years ago in order to combat this problem, the FDA funded additional research to look into the comparative pathogen load between raw and kibbled foods. The study randomly sampled 196 raw and kibbled diets and tested them for Salmonella (along with other pathogens). The study found that raw dog food contained a significantly higher amount of Salmonella than kibbled dog foods (7% vs. 0%). Another study performed in 2006 showed similar results when comparing raw and kibbled dog foods, however, this 2006 study looked at fewer foods in total than the 2014 study.
It is also important to note that at the time of the 2010 to 2012 study there was the largest FDA recall of Salmonella in kibbled dog foods – mostly associated with one manufacturing plant – Diamond Pet Foods. A total of 5 brands of kibble dog foods tested positive for Salmonella between 2010 to 2012 and were recalled. Another eight kibbled diets were voluntarily recalled due to possible contamination due to being manufactured in a facility that also manufactured other foods that were contaminated with Salmonella.
This brings to light that both kibble and raw food CAN be contaminated with Salmonella and other pathogens – which is why things like “test and hold” procedures and routine pathogen testing should be performed prior to release of any food to the dog consumer.
Can Dogs Get Salmonella From Dog Food?
The short answer is – yes – dogs can get salmonella, and there are reported cases of dogs who have gotten very sick and died from salmonella in raw dog food. Clinical signs of Salmonella are: lethargy, decreased appetite, fever, vomiting, and loose stools.
But how often do dogs actually get it from dog food? And how often do dogs actually become ill because they are infected with Salmonella?
As previously discussed in commercially available diets risk of Salmonella infection seems relatively low at around 7%. But if your dog happens to become infected with Salmonella… they may be a non symptomatic carrier, or they may be a symptomatic carrier. Not all dogs who become infected with Salmonella will even display symptoms of disease.
In order to better understand the chances of a dog becoming ill from Salmonella let’s look at another research paper that focused on a Salmonella outbreak in a raw feeding breeding facility.
In a retrospective study looking at a Greyhound Breeding facility that fed raw BARF diets, that were both poor quality meats (containing 4D Meats) and that performed poor handling/sanitation practices – 93% of the dogs tested positive for Salmonella, 44% of the dogs were ill and showing clinical signs of Salmonella, 38% were positive for Salmonella but showed no clinical signs, and 11% of dogs died due to Salmonella.
The conditions that the dogs in the facility lived in were appalling and much different than the typical home pet. However, we can extrapolate from thus data to assess potential risk based of the typical urban dog fed raw. By doing some basic math, if we assume the typical dog fed a commercial raw food has a risk of 7% for eating a food containing Salmonella, then we assume that 44% of those dogs will become ill due to Salmonella – your dog has about a 3% chance of becoming ill due to eating raw dog food.
It should be noted that other studies looking at adult dogs consuming raw dog food, rather than puppies (like in this Greyhound breeding facility) did not show issues with Salmonella illness in dogs. Thus, it is possible that the individual risk of raw may be variable based on the dog’s overall health, age, and lifestyle.
Can and Do Raw Fed Dogs Cause Human Illness?
Even if a dog is not symptomatic and ill due to Salmonella, they may shed the bacteria into the environment, which could potentially cause human disease.
According to a 2007 study, 44% of dogs exposed to Salmonella within their raw diet shed it in their feces, however, only 31% of dogs shed the same strain as within the tested food. In comparison – non of the raw fed dogs fed pathogen free raw shed it in their feces.
If we use the data alone to extrapolate the human exposure risk – we are looking at between 2-3% exposure risk for humans of Salmonella bacteria in the environment of a raw fed dog.
However these laboratory beagles were only fed the raw dog food for a short period of time (2 months), and we know from research that Salmonella can shed in the stool for up to 4-6 weeks making possible exposure possibly higher for chronic feeding of contaminated raw foods.
A follow-up study looked to further evaluate exposure risk in 2009 by sampling dog feces, and vacuum cleaner bags of homes where dogs were raw fed – then they compared those numbers to kibble fed dogs.
There are a couple of very interesting findings of this study – first is that the Salmonella rate in the feces (14%) was much higher than the food contamination rate (5%). This suggests that some dogs may have been exposed in the past to the pathogen and were still shedding it in their feces. This could have happened due to feeding a contaminated treat, by feeding a different contaminated food within the past 4-6 wks, or due to cross contamination in the environment (as Salmonella can live for over a year in soil).
The second thing that is interesting is the kibble fed dogs ALSO had Salmonella in their environment. Exposure to Salmonella for kibble fed dogs may have come from a variety of sources – treats (such as Pig Ears), the environment (Salmonella can live for over a year in the soil), or exposure to other animals contaminated with Salmonella (like reptiles or chickens).
But we can overall conclude that the humans have an increased risk of exposure to Salmonella by about 2% by having a raw-fed dog within the home.
Human Illness From Raw Dog Food?
Generally speaking, human illness from raw dog food is a large concern for most individuals looking to feed or transition their dog to raw. But what is the actual stastical risk of getting sick?
Similarly to dogs, just because you are exposed to Salmonella doesn’t mean that you will become ill. Unlike dogs though – humans have many additional ways to prevent exposure – good hygiene and cleaning practices being the most effective. However, overall raw dog food is usually not recommended for households with immunocompromised individuals, those with very young children (below the age of 6), or those that are elderly.
In order to better understand the human risk associated with feeding a dog raw food, a group of researchers performed an internet-based survey of raw dog feeders to find out if they had ever been ill due to feeding their dog raw.
Out of over 16,000 raw feeders, 99.6% never had any known food borne illness that stemmed from feeding their dogs raw food. 0.2% had suspected cases, and another 0.2% had confirmed cases of food borne illness that steamed from their dog’s food. In other words we are looking at a possible risk of around 0.4% of illness due to Salmonella if your dog eats raw dog food.
It is important to note that dog owners that have kibble fed dogs are no without risk of getting sick from their dog’s food. In the 2010 outbreak of Salmonella from Diamond Pet Food – 49 people were ill, of those 10 people were hospitalized due to a Salmonella infection.
So what is the Risk of Feeding Raw Dog Food?
The underlying point that I really hope you take away from this is the BOTH statements from proponents and critics of raw dog food are correct.
Overall there is more risk feeding a raw dog food than a cooked dog food. Risk is variable based on dog age, health status, sourcing of ingredients, post manufacturing testing for pathogens, treatment of raw, type of raw dog food, etc.
But – there is a risk of Salmonella in kibble fed dogs as well, the main difference here is that the risk of Salmonella in kibble has to do with manufacturing error, it is not an inherent risk of the food itself.
There are ways to mitigate the risk of feeding Salmonella contaminated dog food – including good ingredient sourcing, proper handling, proper storage, routine hygiene, and disinfecting of the environment.
A new wave of raw dog foods have also started to enter the manufactured space – foods using high pressure processing (HPP), fermentation, bacteriophages, and more. These methods offer safer solutions to feeding raw – and foods are often tested after treatment occurs to make sure that no pathogens (such as Salmonella) are present.
Regardless of what type of food you feed your dog you should…
- Practice good hygiene, disinfect bowls, and keep areas clean.
- Do not leave food out for extended periods of time. If serving fresh food, do not allow it to sit out for more than 15 minutes.
- Advocate for routine testing by dog food manufacturers of ingredients, and sourcing from quality suppliers.
- Ask for post manufacturing testing for pathogens using a test and hold procedure.
So what do you think about pathogens in raw dog food? What have you done to mitigate those risks for your own dogs if you feed raw?
Nemser SM, Doran T, Grabenstein M, et al. Investigation of Listeria, Salmonella, and toxigenic Escherichia coli in various pet foods. Foodborne Pathog Dis. 2014;11(9):706-709. doi:10.1089/fpd.2014.1748
Strohmeyer RA, Morley PS, Hyatt DR, Dargatz DA, Scorza AV, Lappin MR. Evaluation of bacterial and protozoal contamination of commercially available raw meat diets for dogs. J Am Vet Med Assoc. 2006 Feb 15;228(4):537-42. doi: 10.2460/javma.228.4.537. PMID: 16478425.
Morley PS, Strohmeyer RA, Tankson JD, Hyatt DR, Dargatz DA, Fedorka-Cray PJ. Evaluation of the association between feeding raw meat and Salmonella enterica infections at a Greyhound breeding facility. J Am Vet Med Assoc. 2006 May 15;228(10):1524-32. doi: 10.2460/javma.228.10.1524. PMID: 16677120
Finley R, Ribble C, Aramini J, et al. The risk of salmonellae shedding by dogs fed Salmonella-contaminated commercial raw food diets. Can Vet J. 2007;48(1):69-75.
Lenz J, Joffe D, Kauffman M, Zhang Y, LeJeune J. Perceptions, practices, and consequences associated with foodborne pathogens and the feeding of raw meat to dogs. Can Vet J. 2009;50(6):637-643.
Anturaniemi, J., Barrouin-Melo, S. M., Zaldivar-López, S., Sinkko, H., & Hielm-Björkman, A. (2019). Owners’ perception of acquiring infections through raw pet food: A comprehensive internet-based survey. Veterinary Record, 185(21), 658. https://doi.org/10.1136/vr.105122
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