Cat & Dog Sensory Perception & Pet Obesity Steven Witherly

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Cat Dog Sensory Perception

• Pet Obesity

Steven Witherly, PhD Technicalproductsinc.net
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Steven A. Witherly, Ph.D.

• B.S Dietetics UCD
• M.S. Food Science UCD
• PhD Nutrition
• Michigan State
• Carnation/Nestle/Leiner/Nutrilite
• Herbalife VP of R and D
• Nutraceutical Consulting
• Book Food Pleasure Explained
• Free copy, just need Email address

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Talk Outline

• Human Perception of Food (Update)
• Evolutionary Perspectives
• Taste Smell
• Update of Canine and Feline Sensory Perception of
  Food
• Taste and Smell
• Palatability
• Pet Obesity Sensory Systems

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Central Thesis I

• Compared with Humans and Mice and Rats and Fruit
  Flies
• Our knowledge of Cat Dog Sensory Perception and
  Food Intake Systems is

Surprisingly Limited Primitive!
Gustation Cats 100 papers..Rat _at_4000!
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Central Thesis II

• 2. Obesity in pets parallels human obesity and
  Diet and Lifestyle may be more common than
  dissimilar.
• 3. Pet Food Perception and Pleasure is closer to
  Human Perception and most Pet Food is Dismally
  Dreary

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Human Sensory Systems

• Tremendous explosion of taste smell science
• Nobel Prize for Physiology to Linda Buck
• Olfaction Receptors
• Palatability theories
• Gut-brain connection
• Obesity implications

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Sensory Homunculus-Human

• 40 of all sensation from the mouth and face
• Intestines about 5 of sensation

Sensation
Intestines
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Human Diet Evolution

• Salt, fat and sugar scare in Past!

Lean meats, berries, whole grains, vegetables,
fruits, honey
Thrifty Gene Hypothesis
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Humans are Cookivores

• Wrangham hypothesis
• Humans evolved with fire 2 million years ago
  vision enlarged, noses shrank
• Aroma receptors down but connections increased
  dramatically (3 Olfactory Brains)
• Aromas associated now with
• Cuisine
• Fire
• Fermentation

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Human Sensory Systems

• Cookivore Theory
• Human sensory systems co-evolved with the use of
  fire
• Evolutionary Past
• Omnivores (Dietary flexibility)
• Like Caloric Density
• Grains, Sugars, Fatty Meats rare
• Complex Palatability Brain wiring
• Five Basic Senses is obsolete concept
• Died with Aristotle

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Human Gustation

• Sense of Taste more Complex
• Up to Eight Basic Tastes or Sensations
• Umami Receptor
• Two Formsunique interactions
• MSG versus 5 Nucleotides
• Signals for Protein in Environment
• Sweet taste combined with fat light up the
  brain!
• Unilever Ice Cream

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Supertasters
Supertasters have higher number of Taste
budsfoods In general are too intense for
these folks. Beware of these People in taste
panels
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Human Olfaction

• 3 Human Genome
• 1000 Gene-Olfactory Receptors
• Finely tunedsome react to just a few aromas
• 40 Pseudogenes!
• Degenerating over last 50,000 years
• No degeneration in other species
• Higher order connections more complex than any
  other species! Secondary and tertiary olfactory
  brains!

DOG and CAT more Direct!
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Exquisite Sensitivity

• For the Skunk odorant, only about 40 receptor
  cells in the human nose need no more than 9
  molecules to give a detectable odor sensation
• Britannica Online, (2001)
• Dogs determine direction of human steps with as
  little as five steps.
• No need to sniffit is continuous!
• Chemical Senses (2005)

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Olfaction
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Olfaction Brain Pathways

• Aromas processed by the limbic system first!

10,000 Glomeruli
40 million receptors
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Sensitivity vs Selectivity

• Just because one species has more Olfactory
  Neurons doesnt mean superiority!
• Primate (macaque) species have remarkable ability
  to pick up carboxylic acids (e.g. propionic,
  heptanoic) gtgt than the rat or dog!
• Olfactory ability depends on 1. odorant binding
  protein 2. aroma desruction, 3. receptor tuning
  and higher order processing!
• Chem. Senses 29 101-109, 2004

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Human Food Palatability Theories

• Sensory Specific Satiety
• Nutritional Conditioning
• Food Pleasure Equation
• Mere Exposure Effect

• Food Aversions
• Evoked Qualities
• Dynamic Contrast
• SuperNormal Stimulus
• SuperTasters

Food Pleasure Taste (Pleasure) Calories
(Calpaldi)
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Cat Dog Sensory Systems
Every Animal Lives in its own Sensory
World (Morley Kare, Monell)
Cats Live in a Different Sensory World Than the
Cat Owner (Li et al. 2005)
Both Dogs Cats are Pre-disposed to Detect
Odors and Taste Associated with Meat (Monell
Connection Fall 2000)
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Olfaction Evolution

• Earliest Sensory System
• Advantages versus Vision/Hearing
• Works in Dark
• Takes no moving parts
• Long range
• Found from prokaryotes to humans
• Makes more connections to brain than any other
  sense
• Odors and Memories are Special

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Olfactions Major Role

• Recognize Nutritious Food
• Perinatal exposure to aromas increase preference
  in dogs
• Chemical Senses 2006 31(3)207-212
• Recognize Poisonous Food
• Locate Sources of Attractive Smells

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Shaggy DogThe Movie

• Question to Tim Allen on what is the hardest
  thing about being a dog?
• Answer Being totally distracted by smells!

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Dogs and Smells I

• "Their world is a very complex, olfactory world.
  They are surrounded by a vast array of different
  things that we are really hardly aware of. It's
  full of colors. It's full of brightness, which
  are smells."
• Dr. Donald Broom, from 60 Minutes, Jan 9th 2005

Dogs almost see the smells
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Dogs and Smells II

• Primary Social Functions
• Individual Recognition
• Maintain Affiliations
• Reduce Competition
• Acuity Stable Among Breeds

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Dog and Olfaction

• Humans have 50 million primary sensory receptor
  cells
• In Dogs the number is one billion!
• Capable of detecting nitroaromatic compounds as
  low as 500 PPT.
• Astonishing Directional capacity
• Spatial fluctuations in odor intensity
• Olfactory Epithelium larger surface area than
  that of the retina (Adrian, 1951)

Human 10 cm2 Cat 20 cm2 Dog 170 cm2
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Dog and Olfaction II

• Greater variety of Olfactory neurons
• Increased odorant detection (variety)
• Greater proportion of Brain tied into olfaction
  than humans
• James Walker in National Geographic
• Dog Human Genome similar
• Share many common diseases
• Ewen Kirkness
• Shared Evolutionary Path???

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Dogs Smell out Disease
Researchers say dogs can be more accurate than
current cancer tests and represent a breakthrough
in cancer detection. 60 minutes, 2005
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Dogs and Taste

• Carnivores (not obligate)
• Human like T1R2 receptor structure
• Love Sweet carbohydrates
• Select sucrose (like Humans Rats)
• Some sweets deadlyXylitol over stimulates
  insulin release
• Bears and Raccoons also love sweets!
• Prefer MSG solutions ( pancreatic flow)

Li, 2005 Torres et al. 2003
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Bitter Taste Genetics T2R

• More genes for Bitter than for the other tastes
• Critical to avoid bitter toxic foods
• gt95 plant poisons bitter
• Humans 25 Mice 34 Chickens 3 Dogs 15.
• Go, Y. Mol Biol Evol 2006, Feb 16.

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Drosophila Basic Tastes

• Receptors for sweet and bitter (and sour and
  salt) just like Cats Dogs! Over entire body!
• Prefers foods that contain amino acids and sugars
  and non bitter compoundsjust like dogs and cats!
• Have sweet receptors for trehalose and aromas
  tuned to yeast fermentation!
• Humans have trehalase enzymes!

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Cat Nutritional Physiology

• No salivary amylase
• Very high protein requirement
• Small stomach, likes energy dense foods
• High Taurine requirement
• Only preformed Vitamin A
• Need Linoleic Arachidonic Acid (animal fat)
• Cant convert tryptophan into niacin
• High L-carnitine requirement
• Quirky Liver Glucokinase

Strict Carnivores
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Cat Olfaction

• Novel Unstudied Species
• Similar to Human and Rat
• George Gomez
• Olfactory Receptors use multiple signalling (more
  complex)
• OR broadly tuned and species-specific
  evolutionary adaptations
• Food without smell reduces eating

Chem Senses. 2005 May30(4)317-26. Epub 2005 Mar
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Cat Olfaction II

• Cat aroma perception uniquedue perhaps to
  unique survival ability of this species.

Gomez, Chem Senses 301-10, 2005
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Owners and Cat Aroma

• Cat Owners have poor ability to recognize their
  own cat by odor alone.
• 25 Cat owners, 52 could recognize them.

Perception. 200231(4)511-2.
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Cats Evolution Taste

• Strict Carnivores (non-plant)
• Solitary Nocturnal (Social?)
• Taste Buds responsive to amino acids
• Poorly developed sodium appetite
• Humans is highly developed
• Shows sodium insensitivity
• Not adapted for long fasting
• Fat Preference? Tallow vs. Corn Oil
• Dislike MCT Oil

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Vomeronasal Organ
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Vomeronasal Organ

• Small canal lined with olfactory cells, complex
  epithelium
• Specifically tuned to certain odors
• Phermonal in nature
• Sexual, feeding, social
• Separate olfactory connections
• Primates mostly non-functional

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Nepatalactone

• Cats sense nepetalactone from catnip using the
  vomeronasal organ
• Sexual Pheromone found in urine?
• Nepatalactone smells like valerian extracts
• Psychoactive compounds when inhaled by humans!
• Found in some Curry Powders!

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Taste vs. Smells

• Taste Response are largely hardwired
• Taste has Relatively high thresholds
• Bitter has the lowest
• Odors work at Low Thresholds
• Odors Need Learning (Most)
• Odors may have specific tunings based on
  evolutionary pressures

Plastic vs. Non-Plastic Sensory Perception
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Olfactory Tuning

• Odorants Binding Proteins (OBPs) bind aromas in
  nose
• Bovine Pigs OBPs show broad specificity for
  medium sized hydrophobic compounds
• Green and Floral notes (Pelosi, 1996)
• MW of 160-200 Daltons
• What about cats and dogs?

Vincent et al. 2000
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Billion Dollar Brands

• Some Pet Food Brands Break into the Top 50 Brands
  Worldwide
• Friskies
• Pedigree
• Whiskas

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Gourmet Dog Food

• Purina Dishes
• Roasted chicken w/pasta and carrots
• Del Monte Kibble Bits
• Adding pasta and vegetables
• Proctor Gamble
• Savory Sauce, bacon, chicken roasted beef

Humanization of Pets
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Pets and Taste Hedonics

• Greatest pleasure is in the taste of a food not
  the aroma!
• Dry Cat Food devoid of food pleasure!
• Natural prey loaded with Umami Tastants
• BLOOD huge hedonic tastant!
• Great Idea Savory Sauce
• she actually jumps on her back legs and tries to
  get into the bowl when she sees me with it
• Modern French Cuisine technique!!!

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Dynamic Contrast Pet Food

• Pet Food lacks Dynamic ContrastHyde Witherly
  theory of Food Palatablity.
• Pet Food is Dreadfully Dreary
• Too hard, too soft, too mushy
• Nestle came up with a process (dogs) that would
  provide some crunch and that wouldnt come out
  mushy WSJ 2006
• Dogs compelled to Novelty in Foods
• Mugford R. 1984

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Dog Sensory Specific Satiety

• SSSdecreased hedonic response to repeated
  exposure to sensory properties of food.
• Dog eat more when offered two different food
  bowls, because of the addition of novel foods in
  familiar diets
• Torres (2003)
• Actually, this is SSS!
• Cats may also prefer Novel Foods
• Stasiak (2002)

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Pet Obesity Rate

• 25-45 of pets obese
• Wall street Journal, March 18th, 2006
• But Death rate has not increased!
• Nutritional completeness
• Antioxidant inclusions
• Appears to parallel the human adult obesity rate
  (currently about 61 overweight-30 Obese)

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Fat Pets Fat People
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Human Obesity Summary

• Increased Intake (200-220 kcals/day)
• Decreased Activity (10-15 less)
• Tasty High Caloric Density Foods
• Brain-Stomach prefers high density
• Rise of Fast Junk Foods
• Many Foods High Glycemic
• Hyperphagia
• Rise of High Fructose Corn Syrup
• Insulin resistance ( Leptin/ Insulin/ Ghrelin)
• Food Intake System Biased Upward
• 100 neurotransmitters

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Purina Life Span Study

• 14 year Study Labrador Retrievers
• Restrict Diet to Ideal Body Weight
• Extended Life Span by 15
• Pet Owners not Likely to see Pets as being
  overweight
• Hi Body Fat induces insulin resistance and
  glucose impairment (like humans)

BT Larson J. Nutr. 2003
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Obesity in Pets

• Pets are fat because humans are fat
• Rich food, lack of exercise
• Spay/Neutering decreases energy expenditure (Kirk
  et al. 2000)
• Unlimited food access
• Dog BMR Decreases w/age not cats
• Do higher carbohydrate foods with high fat table
  scraps encourage fat deposition?

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What You Dont Do!

• Cat was Neutered
• Stays indoors, little exercise
• No one to play with
• Feed Table Scraps
• Cheese, Meat Scrapsfatty cuts
• Unlimited Access to Dry Food
• Fed Wet Food 2x day

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What I did

• More Outdoor Time
• Encouraged my Daughter to Play Chase
• No Dry Food Available
• Only Fancy Feast
• No Scraps
• Purina Friskies for a Treat only

Blue Eyes 2-3 lbs lighter in about a month and a
half! Screamed a lot at me however!
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BARF Diet

• Underground and cult following for the BARF diet.
• BARF Bones and Raw Food
• Cats taste response of fresh kill versus cooked
  meats, dry food?
• Salivation to dry foods???
• My experience in the cat kennels
• Fresh meatgtCannedgtDry

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CatKins Diet

• High Protein Higher fat diet.
• lt 75 grams per day
• Body burns fat to generate glucose
• Lowers insulin appetite
• Cant get fat on low insulin
• CatKins Diet
• Mouse 3 Cho, 40 Protein, 50 Fat
• Dry Food too High in Carbs
• Dr. Greco, Denver AVMA
• Morris Animal Foundation

Mo
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Conclusions

• Limited Understanding of Pet Sensory Evaluation
  or Chemical Senses
• Pets may Share Many Food Pleasure Perception
  Systems with the Human
• Pet Obesity Parallels Rise in Human Obesity and
  may Reflect Societal Issues
• Commercial Pet Food May Maintain Healthy Pet
  Status Despite Obesity Increase
• Complete Nutrition/Antioxidants?

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Thank You!Steven Witherly, PhD