The effect of texturized vegetable protein containing soy carbohydrate on oroileal transit of chromic oxide in cannulated dogs.
Texturized vegetable protein (TVP) from soy is widely used in dog foods but contains indigestible carbohydrate, which may affect intestinal transit. This study was conducted to determine whether TVP affects oroileal transit of the marker chromic oxide (Cr2O3). Four canned diets with Cr2O3 added were fed to eight cannulated mixed-breed dogs in a Latin-square design. The four diets contained reciprocal proportions of protein from TVP (0 to 57%) and from beef (100 to 43%). Ileal effluent was collected during wk 3 of each diet period, prececal apparent digestibility was measured on d 1 to 3 (eight dogs), and rate of appearance of Cr2O3 and chyme was measured on d 4 (six dogs). There was a postprandial delay before any chyme or Cr2O3 was collected, but from 2 to 8 h postprandially the rate of excretion was almost constant (approximately 11%/h). As TVP increased, mean prececal digestibility of protein and carbohydrate decreased from 77 to 71% and from 80 to 62%, respectively. Chyme excretion from 2 to 8 h postprandially increased from 5.8 to 8.3 g DM/h (P < .0001) as TVP increased but times for transit of Cr2O3 and appearance of chyme (as percentage total collected/hour) did not change. Mean times to first appearance and 15, 50, and 95% excretion were 76, 160, 347, and 707 min for Cr2O3 and 60, 147, 338, and 712 min for chyme, respectively. Mean Cr2O3 recovery was 93%. In conclusion, small intestinal transit of Cr2O3 was unaffected by increasing dietary TVP despite marked changes in carbohydrate digestibility.
Hill
R C
RC
Department of Small Animal Clinical Sciences, College of Veterinary Medicine, University of Florida, Gainesville 32610, USA. HillR@mail.vetmed.ufl.edu
Burrows
C F
CF
Ellison
G W
GW
Bauer
J E
JE
D000821:Animal Feed; D000818:Animals; D017608:Chromium Compounds / Q000493:pharmacokinetics*; D004040:Dietary Carbohydrates / Q000494:pharmacology*; D004044:Dietary Proteins / Q000494:pharmacology*; D004063:Digestion; D004285:Dogs / Q000378:metabolism*; D005769:Gastrointestinal Motility / Q000187:drug effects; D007413:Intestinal Mucosa / Q000378:metabolism; D008297:Male; D019518:Postprandial Period; D013025:Glycine max
D017608:Chromium Compounds; D004040:Dietary Carbohydrates; D004044:Dietary Proteins; C023600:chromic oxide