Open Letter to the Senate of the University of Sydney

April 2025

Open Letter to the Senate of the University of Sydney

Dear Senators,

Functional significance and welfare implications of chewing in dogs (Canis familiaris)

I seek to draw your attention to the above important paper, authored by seven academics from within the University. I believe that the paper confirms widespread animal cruelty and consumer fraud** arising from the pet food industry’s promotion of ultra-processed industrial pet food and manufactured ‘chews’. Unfortunately, that cruelty and fraud seems to be endorsed by the University, both in it taking of sponsorship monies from pet food manufacturers and from its sale and promotion of processed foods in its veterinary clinic.

The authors acknowledge:

A characteristic of dogs with dental disease may by [sic] their reliance on humans for their food. When the need to chew for food acquisition is overlooked, as observed in dogs fed processed diets, they crumble easily in the mouth [sic] (47), and the risk of dental disease increases (48).

And:

Harvey et al. (42) found that chewing had a protective effect on dental health, which increased as the range of chewing options increased,

While I take issue with some of the conclusions and assumptions of the authors—including that artificial brand-name ‘chews’ are discussed as being the same as the natural ‘chewy’ canid diet (which in the wild consists of predominantly raw meaty bones) the authors conclude that:

Overall, chewing positively affects individuals throughout all life stages, from conception to senescence.

The value of chewing to positive dog welfare reflects its importance in all four domains of welfare and, overall, positively affects the fifth. Using the Five Domains Framework has demonstrated the welfare benefits of chewing for dogs and confirmed that they largely outweigh any negative consequences.

Cats and ferrets have the same or perhaps greater need for ‘chewing’ on carcasses or raw meaty bones at every meal. However, cats and ferrets can’t be trained to ‘chew’ on artificial treats or artificial toys and thus their needs don’t seem to warrant the concern of this group of researchers.

Unfortunately, the authors fail to mention raw meaty bones—top of ‘the range of chewing options’. Consequently, the researchers don’t establish a baseline standard for the quality, quantity and frequency of chewing, whether for wild or domestic canids. They do, however, mention the brand names of the University sponsor’s inappropriate options: ‘Greenies® (Mars Inc., Kansas City, USA; approximately 58% as carbohydrate)1 and Pedigree® Dentastix (approximately 88% as carbohydrate)’.

In 1993, Dr Douglas Bryden AM, Director of the Centre for Veterinary Education (CVE) noted that a diet of raw meaty bones provides essential health benefits for dogs and cats. He commissioned the definitive chapter Preventative Dentistry, in Veterinary Dentistry Proceedings 212. The chapter established the Australian veterinary standard for the ripping and tearing (chewing) of raw meaty bones necessary for all domestic carnivores.

In 1993 Professor Colin Harvey, who was the course leader at the 5 day Veterinary Dentistry course, noted the significance of the Preventative Dentistry information and enlisted my help in a proposed trial. He wanted advice on the use of raw meaty bones as the reference standard when assessing junk food fed dogs’ gum disease indices. Unfortunately, and allegedly, the vet authorities acting on behalf of junk pet food companies banned the research.

In 2018, Assoc. Prof. Richard Malik wanted Australian vets to be kept informed of the primacy of raw meaty bones in carnivore biology. He commissioned the article Raw Meaty Bones Essentials which lists nine categories of benefit deriving from the consumption of nature’s ideal ‘chew’.

Perhaps the most telling comment on the essential raw meaty bones benefits comes from Dr Tom Hungerford OBE, founding director of the University of Sydney CVE. When 90 years old, upon receiving a copy of my book Raw Meaty Bones: Promote Health, he wrote:

Dear Tom,

Thanks for the book – BRAVO

Tell the people who won’t review their views that: ‘The foolish and the dead never change their opinions.’ Maybe that is an overstatement – as the ‘brain-dead’ may also refuse to revise.

Anyhow there are many who adopt the stance of: ‘Don’t confuse me with facts, my mind is made up.’

Congratulations on the book.

Tom Hungerford
3 October 2001

My concern is that, in continuing to accept sponsorship from pet-food manufacturers who produce ‘food’ that is, on balance, overwhelmingly detrimental to the health of animals—and consequently giving such ‘food’ the imprimatur of the University—the University is engaging in conduct that is at the very least unethical but also, potentially, illegal in respect of:

  • the University’s arrangements with junk pet food companies;
  • the prevention of disease and treatment of dogs and cats under its care,
  • the education of students and
  • expected fair dealings with members of the public.

Please advise what steps, if any, the Senate will be taking to investigate and remedy my concerns.

For example, will you make a public statement eschewing the University of Sydney’s relationships with junk pet food companies and their injurious products?

Thank you for your consideration.

Dr Tom Lonsdale

                          Tom Lonsdale's Signature

** Sydney University Veterinary School confirms widespread criminality

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