Effects of Pectin and Cellulose on Growth, Feed Efficiency, and Protein Utilization, and their Contribution to Energy Requirement and Cecal VFA in Rats

Abstract

Graded levels of cellulose (0 to 20%) or of pectin (0 to 10%) were incorporated in purified diets with either 22 or 8.5% casein as the protein source. Weanling male rats were fed these diets for 4 weeks. Body weight gain, food consumption, feed efficiency, protein biological value, apparent digestion of food, fiber and protein, cecal weight and cecal volatile fatty acids (VFA) were recorded. Cellulose was largely and inert diet diluent causing increased weight gains when protein was limiting but not when protein was sufficient. The 25% disappearance in the gut was due, at least in part, to compaction in the ceca and in increased cecal VFA. Pectin caused progressively greater depressions in body weight gain, food intake and efficiency and protein digestion at both levels of dietary protein. At least part of the 75% disappearance of pectin during passage through the gut could be attributed to increased cecal VFA. However, a rat growth bioassay for energy showed that pectin as well as cellulose, agar and gum arabic contributed no measurable energy to young rats.

Combined dietary folate, vitamin B-12, and vitamin B-6 intake influences plasma docosahexaenoic acid concentration in rats

“…Pectin consequently promotes depletion of endogenous vitamin B-12 through the enterohepatic circulation of the vitamin. Since pectin could affect food intake [19], all four diets were supplemented with pectin to maintain uniform intakes of the diets. Pectin has minimal effects on vitamin B-12 status when the diet contains adequate amounts of this vitamin [18].…”

Plasma choline concentration varies with different dietary levels of vitamins B6, B12and folic acid in rats maintained on choline-adequate diets

“…Pectin consequently promotes depletion of endogenous vitamin B 12 through the enterohepatic circulation of vitamin B 12 . However, since pectin could affect food intake (25) , the B vitaminenriched diet also contained pectin to maintain uniform intakes of the diets. Pectin has minimal effects on vitamin B 12 status when the diet contains adequate amounts of this vitamin (24) .…”

Effect of fermentable carbohydrates on volatile fatty acids, ammonia and mineral absorption in the rat caecum

“…In the rat, the digestibility of carbohydrates reaching the caecum (except for cell wall carbohydrates) is certainly high (80 p. 100 for pectin, according to Hove and King, 1979). Kim, Benevenga and Grummer (1978) estimate that approximately 50 p. 100 of lactose energy which enters the large intestine may be available to the animal as fermentation products.…”