title: Influence of age and body size on gastrointestinal transit time of radiopaque markers in healthy dogs.
abstract: OBJECTIVE
  To compare gastric emptying time, small-intestinal transit time (SITT), and orocecal transit time (OCTT) of radiopaque markers in dogs varying in age and body size and to determine whether fecal variables (ie, consistency and moisture content) are related to gastrointestinal tract transit times in dogs.
  
  
  METHODS
  24 eight-week-old female puppies, including 6 Miniature Poodles, 6 Standard Schnauzers, 6 Giant Schnauzers, and 6 Great Danes.
  
  
  METHODS
  Gastrointestinal tract transit time experiments were performed at 12, 22, 36, and 60 weeks of age. Dogs were fed 30 small radiopaque markers mixed with a meal. Abdominal radiographs were taken. The time at which 50% of the markers had left the stomach (T50) and the time at which the first marker reached the colon were calculated. Fecal moisture content and scoring on the basis of fecal consistency were recorded during the same periods.
  
  
  RESULTS
  Puppies had a shorter mean T50 than adults, and mean OCTT decreased significantly only during growth of large-breed dogs. However mean fecal moisture content significantly increased with age, except in Giant Schnauzers. No effect of body size on T50 was found regardless of age, and no difference was observed between OCTT of small- and large-breed adult dogs. The effect of age on the mean SITT was not significant for any breed. However, a strong positive correlation was recorded between body size and fecal moisture content (r2 = 0.77) or fecal scores (r2 = 0.69) in adult dogs.
  
  
  CONCLUSIONS
  Age affects T50 in small- and large-breed dogs and OCTT in large-breed dogs. However, body size does not affect T50 or OCTT. A relationship does not exist between gastrointestinal tract transit time and fecal variables in healthy dogs.
authors.affiliation: Laboratory of Nutrition and Endocrinology, National Veterinary School of Nantes, France.
authors.forename: Mickaël P
authors.initials: MP
authors.lastname: Weber
authors.forename: Fouzia
authors.initials: F
authors.lastname: Stambouli
authors.forename: Lucile J
authors.initials: LJ
authors.lastname: Martin
authors.forename: Henri J
authors.initials: HJ
authors.lastname: Dumon
authors.forename: Vincent C
authors.initials: VC
authors.lastname: Biourge
authors.forename: Patrick G
authors.initials: PG
authors.lastname: Nguyen
mesh_terms: D000367:Age Factors; D000818:Animals; D001464:Barium / Q000493:pharmacokinetics; D001835:Body Weight / Q000502:physiology; D003287:Contrast Media / Q000493:pharmacokinetics; D004064:Digestive System / Q000000981:diagnostic imaging; D004068:Digestive System Physiological Phenomena; D004285:Dogs / Q000502:physiology*; D005243:Feces; D005772:Gastrointestinal Transit / Q000502:physiology*; D008297:Male; D011860:Radiography, Abdominal / Q000662:veterinary
chemical_list: D003287:Contrast Media; D001464:Barium