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Brain food for puppies

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Abstract

Puppy training is important for successful socialization and owner interaction. Teaching complex tasks concern future sporting, hunting, police or service dogs. Many new puppy owners turn to veterinary practices or obedience schools for advice and assistance. These same people may be taken by foods that claim to support healthy brain and make puppies smarter and more trainable. Such puppy foods feature omega-3 DHA (docosahexaenoic acid) for strong brain development. Newborn puppies have only 10 % of their adult brain mass and considerable growth occurs during the first three months of life. DHA is a key building block for neural tissues and undoubtedly is important in brain function. Puppy foods for brain health highlight DHA, but nutrition is not the only source of brain DHA. The brain can produce DHA from ALA (alpha-linolenic acid), EPA (eicosapentaenoic acid) and DPA (docosapentaenoic acid) or take up blood DHA synthesized in other tissues. Dry foods claiming to bring about DHA-mediated improvement of a puppy's learning ability contain around 0.14% DHA. The function claim is not convincingly supported by published research data. DHA was not the only dietary variable or not reported as such. Taken together the testing of three research groups, increasing dietary DHA, from 0.02% or less to 0.14% or more, was associated with lack of benefit in 7 out of 13 learning and memory tasks. Trainability relates to puppy's ability to understand what the owner or caregiver wants, willingness to learn and remembering the tasks being taught. Nutrient-deficient diets may disrupt trainable performance, but for a puppy fed a regular, nutrient-adequate, commercial food, its intelligence and the method of training determine success. DHA requirement The dietary amount of DHA needed for growth of young dogs has not been determined experimentally. This also applies to the other omega-3 fatty acids, ALA and EPA. The adequate intakes are based on canine milk composition and an arbitrary multiplying factor (1). The recommended total amount of DHA plus EPA is 0.05% in the dietary dry matter. The minimum requirement of ALA equals 0.08% at 1.3% linoleic acid (LA). The high concentrations of DHA in the brain and retinas point at a functional role in these tissues. As happens with rat pups, omega-3 fatty acid deficiency may cause subnormal growth and impaired cognitive and visual development in juvenile dogs. In puppies that had been exposed during gestation, lactation and weaning to a dry diet that approximates omega-3 requirements (ALA-EPA-DHA-LA = 0.14-0.02-0.02-1.75%), electroretinographic abnormalities were not detected (2). Extra DHA pre-and post-weaning Kelley et al. (3-9) have reported on learning ability in puppies born to bitches fed diets containing different amounts of DHA during gestation and lactation and weaned to the same diets. The diets,
Creature Companion 2017; January: 36, 38.
Anton C. Beynen
Brain food for puppies
Puppy training is important for successful socialization and owner interaction. Teaching complex
tasks concern future sporting, hunting, police or service dogs. Many new puppy owners turn to
veterinary practices or obedience schools for advice and assistance. These same people may be
taken by foods that claim to support healthy brain and make puppies smarter and more trainable.
Such puppy foods feature omega-3 DHA (docosahexaenoic acid) for strong brain development.
Newborn puppies have only 10 % of their adult brain mass and considerable growth occurs during
the first three months of life. DHA is a key building block for neural tissues and undoubtedly is
important in brain function. Puppy foods for brain health highlight DHA, but nutrition is not the
only source of brain DHA. The brain can produce DHA from ALA (alpha-linolenic acid), EPA
(eicosapentaenoic acid) and DPA (docosapentaenoic acid) or take up blood DHA synthesized in
other tissues.
Dry foods claiming to bring about DHA-mediated improvement of a puppy’s learning ability
contain around 0.14% DHA. The function claim is not convincingly supported by published research
data. DHA was not the only dietary variable or not reported as such. Taken together the testing of
three research groups, increasing dietary DHA, from 0.02% or less to 0.14% or more, was
associated with lack of benefit in 7 out of 13 learning and memory tasks.
Trainability relates to puppy’s ability to understand what the owner or caregiver wants,
willingness to learn and remembering the tasks being taught. Nutrient-deficient diets may disrupt
trainable performance, but for a puppy fed a regular, nutrient-adequate, commercial food, its
intelligence and the method of training determine success.
DHA requirement
The dietary amount of DHA needed for growth of young dogs has not been determined
experimentally. This also applies to the other omega-3 fatty acids, ALA and EPA. The adequate
intakes are based on canine milk composition and an arbitrary multiplying factor (1). The
recommended total amount of DHA plus EPA is 0.05% in the dietary dry matter. The minimum
requirement of ALA equals 0.08% at 1.3% linoleic acid (LA).
The high concentrations of DHA in the brain and retinas point at a functional role in these tissues. As
happens with rat pups, omega-3 fatty acid deficiency may cause subnormal growth and impaired
cognitive and visual development in juvenile dogs. In puppies that had been exposed during
gestation, lactation and weaning to a dry diet that approximates omega-3 requirements (ALA-EPA-
DHA-LA = 0.14-0.02-0.02-1.75%), electroretinographic abnormalities were not detected (2).
Extra DHA pre-and post-weaning
Kelley et al. (3-9) have reported on learning ability in puppies born to bitches fed diets containing
different amounts of DHA during gestation and lactation and weaned to the same diets. The diets,
which were presumably dry, contained 0.02, 0.08 or 0.14% DHA (4), but ALA and EPA contents are
not disclosed. It is unknown whether DHA was the only dietary variable and whether cognitive
testing was blinded.
Puppies aged 9 weeks were taught to associate a square or circle with the treat location in a two-
arm maze (3, 6). Then, each symbol was seen 5 times in randomized order per session in a total of 60
sessions. Successful was defined as 8 treat rewards in two consecutive sessions with 10 attempts.
The frequencies of dogs with at least one success criterion were 6/19, 8/19 and 13/20 for the low,
medium or high DHA intakes (3, 8).
Extra DHA post-weaning
Seven-week old puppies received a diet containing 0.02 or 0.13% DHA (9, 10); no further dietary
information is provided. Nine weeks later, the puppies were familiarized with a radial arm maze
consisting of eight equidistantly spaced arms. Invisibly from the central platform, the end of one arm
held a food treat as reward for a correct choice in 10 sessions per puppy. Group mean (n = 12)
memory errors were 6.9 and 4.6 for the low- and high-DHA diet.
From 3 weeks of age, puppies consumed a soaked, commercial diet supplemented, as percentage of
total fat intake, with 3% corn oil or 2% DHA plus 1% arachidonic acid (11, 12). Fatty acid sources are
not given. The diet contained less than 0.02% DHA (13). Nine weeks later, each puppy was tested on
navigating through a rectangular maze to a food reward. Group mean (n = 20) failures in solving the
maze during the second set of 9 sessions were 4.2 and 2.8 for the control and DHA supplement.
Three other cognitive tests were without diet effect (12).
DHA dose response
Until one year of age, weanling puppies (16/dietary group) were fed one of three commercial dry
foods differing in ingredients and supplements, and also in omega-3 fatty acids (14). The contents of
ALA-EPA-DHA-LA were 0.12-<0.01-<0.01-2.6, 0.12-0.13-0.10-2.8 and 0.80-0.31-0.19-3.6, in terms of
percentages of the diets as fed. Clearly, DHA was not the only dietary variable. The profile of the
maternal diet was 0.17-<0.01-0.01-2.1.
Seven visual discrimination learning and memory tests were done in blinded fashion. In three tasks,
puppies fed the diet with 0.19% DHA outperformed their counterparts that consumed less DHA. In
two of these tasks there was no DHA dose response: the diets with <0.01 or 0.10% DHA gave similar
results. Despite substantial ALA supply, puppies fed least DHA had reduced retina function as based
on electroretinography.
Literature
1. National Research Council. Nutrient requirements of dogs and cats. The National Academies Press.
Washington, DC, 2006.
2. Heinemann KM, Waldron MK, Bigley KE, Lees GE, Bauer JE. Long-chain (n-3) polyunsaturated fatty
acids are more efficient than α-linolenic acid in improving electroretinogram responses of puppies
exposed during gestation, lactation and weaning. J Nutr 2005; 135: 1960-1966.
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maternal and post-weaning nutrition on puppy trainability.
http://www.breedingbetterdogs.com/article/nutrition-and-dha
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Patent US2005/0075399 A1
5. Anonymous. Eukanuba is the only pet food clinically shown to improve puppies’ ability to learn.
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health care. The IAMS Company, Geneva, 2005, pp 28-33.
7. Hoffman L, Kelley R, Waltz D. For smarter, more trainable puppies: Effect of docosahexaenoic acid
on puppy trainability. IAMS Company, 2007 (ADSB #07356100)
8. Kelley R. Linking puppy trainability and nutrient status. Proceedings NAVC Conference 2008; 22:
1575-1576.
9. Kelley R, Lepine J. Supplementation with docosahexaenoic acid (DHA) improves cognitive
performance in growing puppies. The Veterinarian 2014; Issue 12/April: 10-12.
10. Kelley RL, Lepine AJ. Un supplemento di acido docoesanoico (DHA) nella dieta post-svezzamento
potenzia le capacità d’apprendimento dei cuccioli in crescita. AIVPA Journal 2014; 2: 8-10.
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polyunsaturated fatty acid supplementation on mental stability, problem solving ability, and learned
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enhancement. United States Patent US2003/0194478 A1
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psychomotor, immunologic, and retinal functions in healthy puppies fed foods fortified with
docosahexaenoic acid-rich fish oil from 8 to 52 weeks of age. J Am Vet Med Assoc 2012; 241: 583-
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... Some dry foods claim to bring about DHA-mediated improvement of learning ability in puppies. That claim is not convincingly supported by published research data (31). ...
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Omega-6:3 ratio in dog food The packages of some complete, dry dog foods tout a balanced composition of omega-6 and omega-3 fatty acids. Some other foods claim to have an optimum omega-6:3 ratio (Notes 1, 2). That omega-6 and-3 fatty acids keep a balance or optimum ratio is in itself not extra informative. Complete dog food by definition meets the requirements of the essential omega-6 and-3 fatty acids. More importantly in this context, there is no evidence that higher intakes and/or deviant ratios have additional health benefits in healthy dogs. Linoleic acid (LA) and alpha-linolenic acid (ALA) are essential nutrients and must be present in the diet of dogs. Both LA and ALA are polyunsaturated fatty acids, but their structures differ as indicated by the designations omega-6 and omega-3. In the body, ALA can be converted into other omega-3 fatty acids, particularly EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid). Pre-formed EPA and DHA can be consumed as constituents of fish oils. Advertised omega-6:3 ratios of dog food are generally undefined and may bear upon LA and ALA only or upon all omega-6 and-3 fatty acids. The ambiguity of the ratio can be seen easily. Equal percentage lowering of dietary LA and ALA leaves the LA:ALA ratio unchanged, but diminishes supply of the two fatty acids. In the extreme, the unchanged ratio may even induce fatty-acid deficiency and disease. The total omega-6 to total omega-3 ratio can be lowered to the same extent by either more ALA or more EPA plus DHA, but the two interventions differently affect the dog's fatty acid metabolism. Dog foods may link their highlighted omega-6:3 ratio to a shiny coat and healthy skin (Note 1). Feeding LA or ALA beyond their amounts in regular dog food did not further improve skin and coat condition. The ratio may also be connected with dog's immunity. Feeding EPA plus DHA can influence certain chemical aspects of immunity, pointing to less inflammation. But the impact, if any, on prevention of non-infectious, inflammatory diseases in dogs remains unknown. Inflammatory bowel disease, atopic skin disease and degenerative joint disease (osteoarthritis) are common in dogs. Veterinary anti-atopy and anti-osteoarthritis diets contain inordinate amounts of EPA and DHA. On a group-mean basis, high EPA intake perceptibly reduces the signs of itching in dogs with atopic skin disease (1). In dogs with degenerative joint disease, high intake of EPA plus DHA has a weak, positive effect on mobility (2). Thus, in dogs with inflammatory skin or joint disease, increased dietary levels of EPA and DHA are beneficial. The promotional phrases, omega-6 and-3 fatty acids in balanced composition or with optimum ratio, lack any significance as a descriptor of the food's fatty-acid supply and adequacy. For maintenance of health and treatment of inflammatory disease, the amounts of dietary LA, ALA, EPA and DHA are relevant. Essential fatty acids
... Intake of fish oils, providing both EPA and DHA, may ameliorate atopic dermatitis (28) and osteoarthritis (29)(30)(31), and modulate immunity indicators in dogs (32). There is no solid proof that dietary DHA improves trainability of puppies (33). In aged dogs experienced on cognitive testing, incorporation of 0.4% dried, whole-cell Schizochytrium sp into dry food inconclusively influenced the outcomes of four different cognitive ability tests (14, Note 4). ...
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Methods and composition for improving cognitive function. United States Patent
  • M K Waldron
  • A J Reynolds
Waldron MK, Reynolds AJ. Methods and composition for improving cognitive function. United States Patent US2009/0203786 A1
Dietary methods for canine performance enhancement. United States Patent
  • G M Davenport
  • R L Kelley
  • E K Altom
  • A J Lepine
Davenport GM, Kelley RL, Altom EK, Lepine AJ. Dietary methods for canine performance enhancement. United States Patent US2003/0194478 A1
Nutrient requirements of dogs and cats. The National Academies Press
  • Research National
  • Council
National Research Council. Nutrient requirements of dogs and cats. The National Academies Press. Washington, DC, 2006.
Methods and kits for enhancing ability to learn in a puppy or kitten. United States Patent
  • R L Kelley
Kelley RL. Methods and kits for enhancing ability to learn in a puppy or kitten. United States Patent US2005/0075399 A1
For smarter, more trainable puppies: Effect of docosahexaenoic acid on puppy trainability
  • L Hoffman
  • R Kelley
  • D Waltz
Hoffman L, Kelley R, Waltz D. For smarter, more trainable puppies: Effect of docosahexaenoic acid on puppy trainability. IAMS Company, 2007 (ADSB #07356100)
Linking puppy trainability and nutrient status
  • R Kelley
Kelley R. Linking puppy trainability and nutrient status. Proceedings NAVC Conference 2008; 22: 1575-1576.