" SUMMARY
The use of raw diets is a growing phenomenon among pet owners in developed countries, who in previous decades had embraced the nutritional expertise and convenience offered by processed pet food industries. There is a polarisation in the public debate on the merits of raw feeding, touching as it does on emotionally charged issues such as the care and welfare of pets and a counter‐cultural response to perceived vested interests in the animal feed and other pet care industries. Anecdote, endorsement and firmly expressed opinion have been used on both sides of the debate, and the “campaigning” tone has been aided by large gaps in data.
Given the typical differences between the balance of nutrient groups in raw and processed foods, it is perhaps not surprising that formal investigations have pointed to differences in the gut microbiome between raw‐ and conventionally fed animals, nor that, anecdotally, owners report differences in stool quality. Formal data on a limited number of apparently healthy individuals does not suggest an association between raw feeding and a reduction in periodic episodes of diarrhoea. Nonetheless, it is plausible that, for certain individuals and certain diets, raw feeding may lead to improvements in clinical signs relating to, for example, food intolerances, inflammatory bowel conditions and some other conditions in which dietary influences have been established. What appears less plausible, from a scientific standpoint, are the very broad benefits claimed for raw feeding (without formal evidence) with respect to an extensive range of inflammatory, infectious, neoplastic, endocrine, behavioural and other conditions. Such claims cannot be made directly by manufacturers and retailers in territories where there are stringent evidence rules for commercial advertising. Nonetheless, anecdotes and personal endorsements implying such benefits are promoted in company communications (Natures:menu 2017, BARF World 2018).
With respect to the potential adverse effects of raw feeding, evidence of risk is mostly piecemeal in nature and commonly fails to demonstrate tangible consequences of the identified hazard. Thus, warnings of risks remain susceptible to being dismissed as “scare stories” by proponents of raw feeding. However, there is a growing body of formal investigations and peer‐reviewed publications documenting various aspects of risk and adverse effects associated with raw feeding, although outcomes are still largely documented as case reports or in the context of small studies. There appears little doubt from survey evidence that the prevalence of potentially serious pathogens is substantially higher in raw pet food than in heat‐treated food. Most evidence in this respect has accrued for Salmonella risk. Whilst targeted and systematic monitoring of households may yet be needed to quantify the human health hazards of raw feeding, human salmonellosis outbreak investigations in related situations (contaminated pet treats and dry food, rodent carcasses for feeding reptiles) have clearly demonstrated the risk.
On a precautionary basis, the advice against raw feeding issued by various professional bodies appears justified, especially in the case of the many households that include individuals especially vulnerable to infectious disease. In addition, aspects of raw feeding that may have been underappreciated until recently include the increased frequency and number of antimicrobial drug‐resistant bacteria in raw foods and the risk of exotic pet, livestock and zoonotic diseases associated with imported raw meats.
In conclusion, there is much in the current movement for raw feeding of pets that follows a pattern of counter‐establishment beliefs (appealing variously to ideas of simplicity, intuition and contrarian enlightenment), which are also recognised in many other fields. Such beliefs often use the language and style of formal science while using emotive rationales and relying on anecdote and highly selective data and interpretations as an evidence base. The subsequent development of business and marketing strategies for raw feeding may reinforce a public perception of the reliability of claims made.
Currently, data for the nutritional, medical and public health risks of raw feeding are fragmentary, but they are increasingly forming a compelling body of formal scientific evidence. It appears important that veterinary and public health practitioners and organisations continue to exercise a responsibility to communicate this to both consumers and producers of raw pet food. Given that raw feeding is currently well‐established, it may be that mitigation measures focussed on human health, by emphasising safer handling of products in the home, will have the most significant impact in the short‐ to medium term."
https://onlinelibrary.wiley.com/doi/full...jsap.13000