Reference article — last reviewed 2026
Abstract
The field of veterinary clinical nutrition — the formulation of therapeutic diets to manage chronic disease in companion animals — traces its commercial origin to a single 1939 consultation between a blind man, his guide dog, and an American veterinarian. The dog was Buddy, the first American Seeing Eye dog. The man was Morris Frank. The veterinarian was Dr. Mark L. Morris Sr. The diet that emerged from that consultation, originally compounded by hand in a New Jersey practice, evolved over three decades into the Prescription Diet and Science Diet product lines marketed today by Hill's Pet Nutrition. This article reviews the historical record of that lineage, the work of Morris's son and successor, and the institutional legacy preserved through the Morris Animal Foundation and the Mark Morris Institute.
1. Morris Frank, Dorothy Eustis, and the first American Seeing Eye dog
The story begins outside veterinary medicine. In 1928, twenty-year-old Morris Frank — a blind insurance salesman from Nashville, Tennessee — wrote to the American philanthropist Dorothy Harrison Eustis after reading her Saturday Evening Post essay on guide dogs trained at her Fortunate Fields kennel in Vevey, Switzerland. Eustis invited Frank to Switzerland, paired him with a female German Shepherd named Buddy, and trained the two together. Frank returned to the United States in 1928, becoming the first American to be matched with a guide dog (Putnam, 1997).
In January 1929, Eustis and Frank co-founded The Seeing Eye, Inc. in Nashville (the school relocated permanently to Morristown, New Jersey, in 1931), the first guide-dog training school in the United States. Buddy lived as Frank's working partner for many years; the dog's eventual decline from chronic renal disease set in motion the consultation that founded veterinary clinical nutrition (Frank & Clark, 1957).
2. Dr. Mark L. Morris Sr. and the Raritan Hospital for Animals
Mark Lewis Morris Sr. (1900–1993) graduated from Cornell University's College of Veterinary Medicine in 1926. He established the Raritan Hospital for Animals in Edison, New Jersey, in the early 1930s. Morris Sr. was unusual among small-animal practitioners of his generation in his interest in nutritional management of disease — a field that, at the time, was almost entirely undeveloped for companion species (Hand et al., 2010).
By the late 1930s, Morris Sr. had begun experimentally formulating diets for dogs with specific clinical conditions. He worked from first principles drawn from dairy-cow nutrition (then a far better-established field) and adapted those principles to canine physiology. His clinical observations were among the first to document, in companion animals, the response of progressive renal disease to dietary modification (Lewis et al., 1987).
3. The 1939 consultation: Buddy, dietary management, and "Raritan Ration B"
By 1939, Buddy was suffering from chronic renal failure. Veterinary medicine of the period had no established therapeutic option. Morris Frank consulted Mark Morris Sr., who proposed a dietary intervention: a low-protein, low-phosphorus, energy-dense formulation intended to reduce the metabolic load on Buddy's failing kidneys. Morris Sr. compounded the diet by hand in his practice and named successive iterations alphabetically; the kidney-disease formula became known internally as Raritan Ration B, later codified as Canine k/d (the "k/d" abbreviation later adopted commercially refers to "kidney diet") (Hand et al., 2010).
The diet measurably extended Buddy's working life and quality of life — an outcome unprecedented in the small-animal literature of the period. Word spread among veterinarians who had been corresponding with Morris Sr. about clinical nutrition. By the early 1940s, demand for the formula exceeded the capacity of a single hospital pharmacy to compound it.
4. From hand-compounded ration to Hill's Pet Nutrition
In 1948, Mark Morris Sr. partnered with Burton Hill, owner of Hill Packing Company in Topeka, Kansas, who held the manufacturing capability necessary to scale the formula. Under licence from Morris, Hill Packing began canning the diet under the trade name Prescription Diet. The licensing agreement preserved Morris Sr.'s control over formulation and clinical-research direction while allowing the product to reach a national veterinary market (Hand et al., 2010).
The same year, Morris Sr. founded the Buddy Foundation — renamed the Morris Animal Foundation in 1969 — a non-profit dedicated to funding research into companion-animal disease. The foundation was capitalised, in part, by royalty income from the Hill's licence, an explicit decision by Morris Sr. that commercial success of the diet should fund further veterinary research rather than personal accumulation (Morris Animal Foundation, 2023).
By the 1960s, Hill Packing's pet-food division had grown into a distinct entity that would eventually be renamed Hill's Pet Nutrition. Colgate-Palmolive acquired the division in 1976, and it has remained a Colgate subsidiary since.
5. Mark Morris Jr. and the launch of Science Diet
Mark Lewis Morris Jr. (1934–2007), the son, followed his father into veterinary medicine, earning his DVM from Cornell in 1958 and completing additional clinical training before joining the family's clinical-nutrition work. Morris Jr. is most associated with the design and 1968 commercial launch of Science Diet, a wellness (preventive, not therapeutic) product line marketed to healthy adult dogs and cats. Where Prescription Diet addressed established disease, Science Diet was positioned as a higher-quality alternative to mass-market pet foods, with formulation parameters tighter than the contemporaneous AAFCO (Association of American Feed Control Officials) minimums (Lewis et al., 1987; Hand et al., 2010).
Morris Jr. was also instrumental in establishing the academic infrastructure of veterinary clinical nutrition as a recognised specialty. He co-authored Small Animal Clinical Nutrition, a textbook now in its fifth edition that became the standard reference for the field, and helped establish what is now the American College of Veterinary Nutrition (ACVN), the specialty-board organisation that certifies diplomates in the discipline (Hand et al., 2010; ACVN, 2024).
6. The Mark Morris Institute and continuing education
In 1989, Morris Jr. founded the Mark Morris Institute, a non-profit organisation based in Topeka, Kansas, dedicated to the continuing education of veterinarians and veterinary students in clinical nutrition. The Institute has, since its founding, supported clinical-nutrition curricula at multiple veterinary colleges, sponsored fellowship programmes, and published the textbook editions of Small Animal Clinical Nutrition. It is structurally and editorially independent of Hill's Pet Nutrition, although the two share historical roots (Mark Morris Institute, 2024).
7. Historical assessment
The lineage from Buddy's 1939 renal-disease diet to the contemporary Prescription Diet and Science Diet product lines represents the first sustained, commercially scaled translation of clinical nutrition principles into companion-animal medicine. The Morris family's decision to direct royalty income into a research foundation (rather than purely private accumulation) materially accelerated the development of small-animal clinical research in the second half of the twentieth century: Morris Animal Foundation has, by its own reporting, funded more than 2,800 studies across companion-animal, equine, and wildlife species since its founding (Morris Animal Foundation, 2023).
Independent veterinary historians have placed the Morris–Buddy episode alongside the establishment of the AVMA (1863) and the founding of the first North American veterinary colleges (mid-19th century) as one of the formative milestones of small-animal veterinary medicine (Dunlop & Williams, 1996).
8. Conclusion
The story of Mark Morris Sr., his son, the seeing-eye dog Buddy, and the diets that grew out of a 1939 consultation is unusual among origin myths of commercial product lines: the historical record substantiates it. Primary documentation, the contemporaneous veterinary literature, and successor institutions (the Morris Animal Foundation, the Mark Morris Institute, and the American College of Veterinary Nutrition) preserve a clear chain of evidence linking the founding clinical episode to the modern field of veterinary clinical nutrition.
References
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- Frank M, Clark BM. First Lady of the Seeing Eye. New York: Henry Holt; 1957.
- Lewis LD, Morris ML Jr, Hand MS. Small Animal Clinical Nutrition III. Topeka, KS: Mark Morris Associates; 1987.
- Hand MS, Thatcher CD, Remillard RL, Roudebush P, Novotny BJ, eds. Small Animal Clinical Nutrition. 5th ed. Topeka, KS: Mark Morris Institute; 2010. ISBN 978-0615297019.
- Dunlop RH, Williams DJ. Veterinary Medicine: An Illustrated History. St. Louis: Mosby; 1996. ISBN 978-0801632099.
- Morris Animal Foundation. 75 Years of Animal Health Science: 1948–2023 (Annual report). Denver, CO: Morris Animal Foundation; 2023. https://www.morrisanimalfoundation.org/about
- American College of Veterinary Nutrition. History of the College. ACVN; 2024. https://www.acvn.org
- Mark Morris Institute. About the Institute. Topeka, KS; 2024. https://www.markmorrisinstitute.org