Anatomy and Physiology

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Anatomy and Physiology

• Digestion and Absorption

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Mastication

• Mechanical reduction of the ingested food
  particles
• Food is mixed with saliva forming a bolus
• Tongue (muscular organ) moves food around mouth
  to form and push bolus down esophagus

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Tongue

• Taste buds more discriminatory when food is in
  a native or unprocessed state (able to
  distinguish between harmful and proper foods)

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Taste Buds

• Humans
• 5-6 types of taste buds sour, bitter, salty,
  umami (meatiness) and sweet (possibly fat)
• sweet receptor made up of two coupled proteins
  generated by two separate genes
• Tas1r2 and Tas1r3

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Cats Cant Taste Sweet

• Cats have about 470 taste buds
• lack 247 base pairs of the amino acids that make
  up the DNA of the Tas1r2 gene
• does not code for the proper protein
• Why do you think it is a good thing that cats
  cant taste sweet things?

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Cats Cant Taste Sweet

• cats can taste things humans cannot
• ATP
• signal for meat
• most major pet food manufacturers use corn or
  other grains in their meals
• Cat food 20 carbohydrates
• Is this causing diabetes in cats?

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Cats Cant Taste Sweet

• The suggestion that cats may have difficulty
  adapting to high-carbohydrate meals appears to be
  based on two observations
• (1) cats lack glucokinase, an enzyme used to
  phosphorylate glucose inside cells
• (2) cats lack salivary amylase and, compared with
  dogs, may have lower activities of the enzymes
  involved in carbohydrate digestion

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Cats Cant Taste Sweet

• For glucose to be used by a cell, it must enter
  the cell and be phosphorylated by glucokinase
• Lacking glucokinase activity, cats rely on other
  enzymes, including hexokinase
• less efficient than glucokinase when glucose
  concentrations are high, cats have considerably
  more hexokinase, phosphofructokinase and pyruvate
  kinase enzyme activities than dogs

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Dogs Cant Taste Salt

• Dogs have only about 1,700 taste buds that people
  (10,000) do, and their distinct sense of taste
  is actually quite poor

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Diseases of the Oral Cavity

• Oral Tumor can arise from the bone, teeth or
  soft tissue structures of the lower (mandible) or
  upper (maxilla) jaw, or the tongue or pharynx

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Oral Tumors

• most are malignant
• malignant melanoma and squamous cell carcinoma
  are the most common oral tumors in dogs
• squamous cell carcinoma is the most common oral
  tumor in cats

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Oral Tumors

• Diagnosis
• Physical exam
• Blood tests
• Aspiration
• MRI
• Chest X-rays
• Treatment
• Surgery
• Radiation
• Chemotherapy

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Periodontal Disease

• Preventable
• Shows up at 3-4 years of age
• Clinical Signs
• Inflamed gums
• Tartar build up
• Loose teeth
• Difficulty eating
• Halitosis

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Periodontal Disease

• Mainly caused by bacteria Peptostreptococcus,
  Actinomyces, and Porphyromonas
• Treatment
• Dental cleaning (vet)
• Brush teeth daily (home)
• Diet (tartar contro, i.e. T/D)
• Tooth extraction

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Stomatitis

• Painful, inflammation of the mouth
• Potential to be fatal

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Periodontal Disease

• Periodontal disease can lead to heart disease
• and kidney disease if left untreated