4. Discussion
This study was designed to examine the reasons behind the abandonment/discontinuation of RMBDs by dog owners. The primary reasons for abandoning raw meat feeding were intolerance, disease (especially gastrointestinal disease), and lack of acceptance.
The dog population in the present study showed a balanced sex ratio and neutering status. A very similar distribution was also shown in other German studies [
24]. The age distribution in the present study compared to the German average [
23] shows slightly more dogs in the age category 3–5 years among the raw-fed dogs and slightly fewer in the categories 0–2 years and over 10 years.
The weight of the study dogs showed differences compared to the German average [
23]. In the study population, there were significantly more dogs that weighed more than 40 kg and significantly fewer dogs weighing less than 10 kg. This shows that dogs that have stopped being fed raw diets tend to be bigger than the German average.
There were significantly more dogs in households with two or even more than two dogs compared to the German average [
23]. On the one hand, this difference may be due to time, as the survey from Göttingen was conducted 5 years ago [
23]. However, it is still possible that dog owners who prefer raw meat feeding are more likely to have more than one dog. It is also possible that bigger dogs and households with more than one dog are more likely to quit raw feeding because it’s more expensive and time-consuming than for smaller or fewer dogs in the household.
Mixed-breed dogs were most frequently reported in the study, which is consistent with observations of the overall dog population in Germany. The breeds mentioned afterward fit with national statistics in terms of their popularity [
23]. All in all, the study population reflects a representative German dog population.
Nevertheless, there were significantly fewer mixed breeds and more pedigree dogs compared to the national comparison. Therefore, pedigree dogs seem to stop being fed RMBDs more frequently than mixed-breed dogs. A study in cats showed that pedigree cats are more likely to eat a raw diet than others [
25], so it could also be the overall population of raw-fed dogs that included more pedigree than mixed-breed dogs.
According to our results, the majority switched their feeding due to their dog’s wellbeing and the food’s impact on it. The most frequently mentioned primary reasons were intolerance, illness of the dog, or lack of acceptance of the food. Just after this, factors including financial considerations, logistical demands, and time constraints were cited as reasons for discontinuation. These factors predominantly pertain to the owner and their specific circumstances. Consequently, reasons for discontinuation were mostly dog-related.
Intolerance refers to gastrointestinal signs that occurred either in isolation or in combination with other signs. This is consistent with the study of Effenberger [
13], who also found a higher rate of diarrhea in dogs that were fed raw meat-based diets than in dogs fed with cooked meat. Schmidt et al. [
26] showed that dogs fed RMBDs displayed a higher dysbiosis index as well as some other changes in their fecal microbiome and metabolome compared to those fed with commercial dry or wet food. To what extent an altered microbiome is involved in the development of gastrointestinal diseases has been studied previously [
27,
28,
29,
30,
31] and requires further research to make a clear statement.
One striking aspect of the results was the significantly higher occurrence of gastrointestinal diseases in comparison to all other mentioned diseases. When asked about the type of disease, 44% of owners who switched their feeding due to a gastrointestinal disease reported inflammatory bowel disease (IBD). This disease causes various gastrointestinal signs. Diagnosis and classification are made using biopsy samples from the gastrointestinal tract, from which the type of inflammation is determined [
32,
33,
34,
35]. It is questionable whether all dogs that were reported as having an IBD in the questionnaire received a confirmed diagnosis via endoscopy and biopsy sampling or whether some of them only had a suspected diagnosis. Even though the authors could not confirm all dogs had a confirmed diagnosis of IBD, these dogs experienced chronic gastrointestinal signs consistent with a chronic enteropathy (CE).
Overall, 37% (
n = 300) of participants quit feeding a raw meat-based diet due to gastrointestinal signs (
n = 196, 24%) or a gastrointestinal disease (
n = 104, 13%). The prevalence of chronic enteropathies is not that easy to determine. The review of Dandrieux et al. [
36] showed a prevalence ranging from 1% [
37] to 17.8% [
38]. In two studies looking for the prevalence of CE in dogs with predicted acute hemorrhagic diarrhea syndrome (AHDS) [
39] or parvovirus infection [
40], the control groups showed a prevalence of 12% [
40] and 13% [
39]. When considering just the gastrointestinal diseases of all dogs that stopped receiving raw food diets, the prevalence is 13%, which matches the control dogs in the aforementioned studies. Adding all the dogs with gastrointestinal signs, the prevalence rises to the aforementioned figure of 37%, which is between the prevalence for past AHDS disease (28%) and parvovirus infection (42%). Unfortunately, the authors do not know if all the dogs that had gastrointestinal problems in the present study really suffered from chronic enteropathy or if they only showed temporary gastrointestinal problems that led to a change of diet.
Of the participants who cited gastrointestinal illness in their dogs as the primary reason for discontinuation (n = 104), a minority of 17% (n = 18/104) reported that a gastrointestinal disease already affected the dogs before starting an RMBD. Accordingly, most dogs (83%, n = 86/104) developed this disease during or after the feeding of raw meat.
The duration of feeding a raw diet also differed depending on the reasons for discontinuation. Dogs that refused the raw diet were fed for a shorter period than ones that gained weight or developed an illness over a long period of time, but there was no statistically significant difference. In particular, as weight gain is often a process that takes time and some RMBD packages are higher in fat and energy than declared (or the case of a homemade diet, difficult for owners to observe), it is not surprising that some dogs gained weight [
41].
The new diet after a raw meat diet was most likely be a self-cooked ration if many of the reasons that were important to the owners—such as knowledge of composition, natural and species-appropriate feeding, and lack of trust in the pet food industry—were to be considered. However, the results show that a self-cooked ration was chosen only in about a quarter of the cases. Most participants switched to dry food. Looking at the choice of new food in relation to the reasons for discontinuation, the following things stand out. Home-cooked rations were fed less frequently than dry food in all cases and less frequently than wet food in almost all cases (excluding illness). A predominant transition from a raw to a home-cooked diet was observed neither for the entire population nor for individual dropout groups.
Dry food was fed significantly more often than wet food for reasons such as food being too expensive, too much effort, or taking too time. These results are consistent with our assumptions, as dry food is generally cheaper in terms of energy content per quantity than wet food and is also easier to feed and transport, e.g., when traveling or during holidays. In the case of intolerance and illness, dry food was also fed significantly more frequently. This could possibly be due to the larger range of dry formulated commercially available hydrolyzed and gastrointestinal diets.
In addition to a regular adult diet and a self-made ration, the switch was primarily to an anti-allergenic or a hypoallergenic diet and a gastrointestinal diet. These results again align with the results on discontinuation due to illnesses and intolerances.
Since the development of the raw meat feeding trend, veterinarians and scientists have expressed concerns regarding this feeding practice. The focus has primarily been on contamination with pathogenic microorganisms [
5,
11,
12,
13,
14,
15,
16,
17,
18,
19,
20] and inadequate contents of trace elements, minerals, and vitamins [
3,
6,
7,
8,
9,
10]. The study’s findings reveal a disparity between the reasons why the science community advises against this feeding method and the actual reasons why dog owners opt to discontinue it.
As the questionnaire was administered online, the authors surveyed dog owners with a high level of interest in their dogs and their dogs’ feeding habits. This may have led to an overrepresentation of dog owners with considerable knowledge about dog feeding and their dogs’ health status. The questionnaire was only addressed to owners who had stopped feeding raw meat, so we cannot determine what percentage of the total number of owners feeding raw meat the study population represents. Naturally, the research is limited to dog owners who must have basic knowledge of technology and access to the technology itself, as well as be willing to participate in an online survey. The questionnaire was largely promoted through social media, with some breed- and disease-related groups also sharing it. This could have led to possible preconceptions among the participants. Since no further survey was conducted to ask people for their reasons for switching their pet’s diet (besides switching from a raw diet), the authors lack a control group and a direct comparison. However, due to the broad distribution and numerous participants, the results should represent a realistic population. As the questionnaire did not ask for any demographic information from the owners, the authors cannot assure that all respondents live in Germany, neither do the authors know if there was a bias in the age, sex, or educational status of the respondents.