Interaction between dietary cellulose content and food intake in cats

Cats maintained bulk intake but reduced energy intake when their diets were diluted with celluflour or kaolin (1,2). It is not clear, however, whether a lowered palatability or gastric filling was the predominant reason for the reduction in energy intake in cats. By contrast, it was demonstrated that gastric filling does not play a very important role in limiting energy intake in dogs during maintenance (3,4). Anecdotal reports from clients in our nutrition consultation practice suggested that in cats, fibrous cellulose powder was more efficient in decreasing food intake during weight reduction than it was in dogs. The present study was carried out to compare the effects of cellulose on feed intake in cats and dogs. Additional aims were to collect more data on the relative importance of bulk, volume, and palatability in cats eating diluted diets and to establish the level of crude fiber from cellulose that limits food intake in cats during time-restricted feeding, as recommended for reducing diets. In the present investigation, cats were fed increasing levels of cellulose added to a complete moist cat food. Additionally, they were offered a food without added cellulose after they had consumed a high-cellulose diet. The hypothesis was that if they would eat considerable amounts of undiluted food without cellulose after they had eaten diluted food with cellulose, then the lower food intake from diluted food with cellulose would be due mainly to low acceptability of the diluted food, and if the cats would eat small amount of undiluted food after the intake of diluted food, the effect would likely be due to gastric filling. The experimental design, including the type of cellulose, was kept as close as possible to the earlier experiment of Dobenecker and Kienzle (4) in dogs, to enable comparison of results in both species.