Pottenger’s cats revisited: A classic example of a nutritional deficiency of taurine

Abstract

Objective. From 1932 to 1942, Dr. Francis Marion Pottenger Jr. conducted a group of experiments to determine the effects of heat-processed food on cats. Cats fed an all-raw diet were healthy while cats fed the cooked meat diet developed various health problems. At the time of Pottenger's studies the heat labile amino acid taurine had not yet been identified as essential for cats. This work shows that the deficiencies Pottenger identified in cats correspond with those of a taurine deficiency and are the direct result of the lack of taurine in the feline diet.

Methods. Pub Med and EBSCO Host were utilized to obtain journal articles. The Pottenger papers were obtained from the Price-Pottenger Nutritional Foundation. The physiological effects of a cooked diet described by Pottenger in his papers were compared with data from recent studies on taurine deficiency in the feline diet.

Results. Pottenger’s main observations of near and far sightedness, cardiac leasions, increased stillbirth, low birthweight, poor kitten survival, and developmental abnormalities each correspond to published descriptions of taurine deficiency in cats with multiple references for each described condition.

Conclusions. Taurine deficiency is a strong explanation for the symptoms observed by Pottenger in his cat studies. Pottenger’s own conclusion that there was an ‘as yet unidentified, heat-labile protein factor’ is realized in taurine.

Full text

Pottenger’s Cats Revisited: A Classic Example of a
Nutritional Deficiency of Taurine
Introduction
From 1932 to 1942, Dr. Francis Marion Pottenger Jr. conducted a group of
experiments to determine the effects of heat-processed food on cats.1,2 As part of
the studies, one group of cats was fed a diet of two-thirds raw meat, one-third raw
milk, and cod-liver oil while the second group was fed a diet of two-thirds cooked
meat, one-third raw milk, and cod-liver oil. The cats fed the all-raw diet were
healthy while the cats fed the cooked meat diet developed various health
problems including near and farsightedness, cardiac lesions, increased incidence
of stillbirths, low kitten survival, low birth weight, and poor growth and
development.
At the time of Pottenger's studies taurine had not yet been identified as an
essential amino acid for cats. According to the Nutrient Requirements of Cats,
revised edition, 1986, the taurine requirement for the domestic cat is 400 mg/kg
for kittens and adult cats and 500 mg/kg for pregnant females.3 Cats lack the
ability to synthesize adequate amounts of taurine from precursors.4 This fact
makes taurine an essential amino acid in the feline biological system and
therefore it must be provided completely by the diet.
Pottenger’s publications have been widely cited and promoted as justification for
including supplemental digestive enzymes in the human diet.5,6
Abstract
Objective. From 1932 to 1942, Dr. Francis Marion Pottenger Jr. conducted a
group of experiments to determine the effects of heat-processed food on cats.
Cats fed an all-raw diet were healthy while cats fed the cooked meat diet
developed various health problems. At the time of Pottenger's studies the heat
labile amino acid taurine had not yet been identified as essential for cats. This
work shows that the deficiencies Pottenger identified in cats correspond with
those of a taurine deficiency and are the direct result of the lack of taurine in the
feline diet.
Methods. Pub Med and EBSCO Host were utilized to obtain journal articles. The
Pottenger papers were obtained from the Price-Pottenger Nutritional Foundation.
The physiological effects of a cooked diet described by Pottenger in his papers
were compared with data from recent studies on taurine deficiency in the feline
diet.
Results. Pottenger’s main observations of near and far sightedness, cardiac
leasions, increased stillbirth, low birthweight, poor kitten survival, and
developmental abnormalities each correspond to published descriptions of
taurine deficiency in cats with multiple references for each described condition.
Conclusions. Taurine deficiency is a strong explanation for the symptoms
observed by Pottenger in his cat studies. Pottenger’s own conclusion that there
was an ‘as yet unidentified, heat-labile protein factor’ is realized in taurine.
Conclusions
• Based on the observed symptoms in Pottenger’s cats, they were
deficient in taurine.
• Pottenger’s conclusion that “there was likely an ‘as yet unknown’
protein factor that may have been heat sensitive”2 was correct.
• Pottenger’s Cat studies should not be cited as justification for
supplemental digestive enzyme use.
Discussion
According to the Nutrient Requirements of Cats, revised edition, 1986, the
taurine requirement for the domestic cat is 400 mg/kg for kittens and adult cats
and 500 mg/kg for pregnant females.3 Cats lack the ability to synthesize
adequate amounts of taurine from precursors.4 This makes taurine an essential
amino acid in the feline biological system and therefore it must be provided
completely in the diet. Taurine is destroyed by cooking and it has been shown
that cats with a diet consisting of heat processed foods have a lower plasma
taurine concentration.8-11
Throughout the ten years that Pottenger used to conduct the cat studies he
observed six major conditions in cats that were fed cooked meat diets that cats
fed raw meat did not develop. These six deficiencies are near and
farsightedness, increased incidence of stillbirths, low kitten survival, low birth
weight, and poor development. Beginning in 1973 when it was reported that
taurine was an essential amino acids for cats through 1990 there was a steady
progression of research describing the effects and function of taurine on various
systems in the cat. Table 1 summarizes major findings that match the conditions
observed by Pottenger that have correspondingly similar deficiency symptoms in
cats lacking taurine in the diet. All these deficiency symptoms can be prevented
or treated with the addition of taurine to the diet.
Taurine deficiency is a solid explanation for the symptoms observed by Pottenger
in his cat studies from 1932 to 1942. Current research shows that there are
strong similarities between taurine deficiency and the abnormalities, symptoms,
and degeneration Pottenger reported in his cats that were fed the cooked meat
diet. The only source of taurine for Pottenger’s cats was meat and it is now well
understood that cooking degrades this amino acid. This degradation leads to
reduced bioavailability and biopotency of taurine. Therefore the cats that
received the cooked meat diet were taurine deficient and the abnormalities
observed by Pottenger were a result of this deficiency.
820.4
References
1. Pottenger FM Jr.: Heat labile factors necessary for the proper growth and
development of cats. J Lab Clin Med, 1939, 25(6):238-240.
2. Pottenger FM Jr.: The effect of heat-processed foods and metabolized vitamin D
milk on the dentofacial structures of experimental animals. Am J Orthod Oral Surg
1946, 32:467-85.
3. Committee on Animal Nutrition, National Research Council, Nutrient Requirements of
Cats revised ed. National Academy Press, 1986.
4. Knopf K, Sturman JA, Armstrong M, Hayes KC: Taurine: An essential nutrient for
the cat. J Nutr 1978, 108:773-778.
5. Pottenger FM: Pottenger’s Cats: A Study in Nutrition, 2nd ed. Price Pottenger Nutrition,
Lemon Grove, CA, 1995.
6. Loomis HF: Enzymes, the Key to Health. 21st Century Nutrition Publishing, Madison,
WI, 2005.
7. The Price-Pottenger Nutrition Foundation. www.ppnf.org (last accessed 4.7.14)
8. Hickman MA, Rogers QR, Morris JG: Taurine balance is different in cats fed
purified and commercial diets. J Nutr 1992, 122(3):553-9.
9. Hickman MA, Rogers QR, Morris JG: Effect of processing on fate of dietary
taurine in cats. J Nutr 1990, 120(9):995-1000.
10. Kim SW, Rogers QR, Morris JG: Dietary antibiotics decrease taurine loss in cats
fed canned heat-processed diet. J Nutr 1996, 126(2):509-515.
11. Hickman MA, Katan MB: Quercetin in foods, cardiovascular disease, and
cancer. In Flavonoids in Health and Disease, Rice-Evans CA, Packer L. eds. Marcel
Dekker, Inc., New York: 447-463, 1997.
12. Rabin AR, Hayes KC, Berson EL: Cone and rod responses in nutritionally
induced retinal degeneration in the cat. Invest Ophthalmol 1973, 12:694-704
13. Hayes KC, Rabin AR, Berson EL: An ultra structural study of nutritionally
induced and reversed retinal degeneration in cats. Am J Pathol 1975, 78(3):505-24.
14. Hayes KC, Carey RE, Schmidt SY: Retinal degeneration associated with taurine
deficiency in the cat. Science 1975, 188(4191):949-51.
15. Schmidt SY, Berson EL, Hayes KC: Retinal degeneration in cats fed casein. I.
Taurine deficiency. Invest Ophthal 1976, 15(1):47-52.
16. Neumann SM: Retinal degeneration relating to taurine deficiency in a cat. Mod
Vet Pract 1984, 65(5):381,384.
17. Sturman JA, Gargano AD, Messing JM, Imaki H: Feline maternal taurine
deficiency: effect on mother and offspring. J Nutr 1986, 116:655-667.
18. Pion PD, Kittleson MD, Rogers QR, Morris JG: Myocardial failure in cats
associated with low plasma taurine: a reversible cardiomyopathy. Science 1987,
237:764-768.
19. Novotny MJ, Hogan PM, Flannigan G: Echocardiographic evidence for
myocardial failure induced by taurine deficiency in domestic cats. Can J Vet Res
1994, 58:6-12.
20. Dieter JA, Stewart DR, Haggarty MA, Stavenfeldt GH, Lasley BL: Pregnancy failure
in cats associated with long-term dietary taurine insufficiency. J Reprod Fertil
Suppl 1993, 47:457-463.
21. Sturman JA, Moretz RM, French JH, Wisniewski HM: Taurine deficiency in the
developing cat: persistence of the cerebellar external granule cell layer. J Neurosci
Res 1985, 13(3):405-16.
22. Sturman JA, Mortez RC, French JH, Wisniewski HM: Postnatal taurine deficiency
in the kitten results in a persistence of the cerebellar external granule cell layer;
correction by taurine feeding. J Neurosci Res 1985, 13:521-528.
23. Hayes KC, Trautwein EA: Taurine deficiency syndrome in cats. Vet Clin North Am
Small Anim Pract 1989, 19(3):403-13.
Robert T. Davidson, Jonathan Emlet
Nutrition and Human Performance, Logan University, Chesterfield, MO 63006
Results Methods
The F.M. Pottenger Jr. papers describing the cat studies were obtained from the
Price-Pottenger Nutritional Foundation.7 The physiological effects of a cooked
food diet described by Dr. Pottenger in his papers were studied and his findings
were compared with data from more recent defining studies on taurine deficiency
in the feline diet.
TABLE 1. Pottenger's observed deficiency symptoms and corresponding
taurine deficiency description references.
Conditions observed by Pottenger in
cooked meat-fed cats
Published corresponding taurine
deficiency symptoms references
Near and far sightedness Retinal degeneration 12-17
Cardiac lesions Dilated cardiomyopathy18
Myocardial failure19
Higher incidence of stillbirth Smaller litter size17,20
Increased incidence of stillbirth17,20
Lower kitten survival rate Lower kitten survival rate17,20
Lower birth weight Low birth weight17,20
Developmental abnormalities Neurological abnormalities21
Hind leg development abnormalities21
Peculiar gait21
Thoracic kyphosis21
Reduced growth rate22
Abnormal growth rate17,23
Abnormal structural development17,23
Abnormal neurological function17-23