With strict carnivores the intestinal tract is much shorter than in other animals unlike cats and dogs the intestinal tract of their prey last thus avoiding the plant fiber of the intestinal contents. Although plant is not the only source of fiber. Animal fiber is extremely important in the nutrition of strict carnivores. Dietary fiber is the indigestible portion of food derived from plants, there are different types of plant based fiber. There are soluble and insoluble fibers as well as rapidly fermentable and slowly fermentable fibers.
These fibers include pectins and gums can act like a gel and draw water into the colon. Fermentable fibers can also be fermented by bacteria in the gut to produce short chain fatty acids which can be utilized by the cells of the colon to help them function. Most pet foods have both which helps with adding moisture to stool and decrease gastrointestinal transit time, which can be beneficial in the case of constipation.
Moderately fermentable fiber sources include: brans, soy fibers, soy hulls, and beet pulp, the argument do cats need it, well no if they ate prey which contain these fibers in their stomach which is completely digested, cats thrive on protein and fat
Cats have developed biological and behavioural traits when it comes to prey like their larger counter parts, killing their prey to get the nutrients needed. In fact, in live they report an instance: The presumably vegan owners of a kitten brought the little guy into the Lort Smith Animal Hospital in July. The kitten was in very bad shape. “It was extremely weak and collapsed when it came in. It was almost non-responsive,” according to veterinarian Leanne Pinfold.
As it turns out, the kitty’s owners had been feeding him a diet of potatoes, rice milk and pasta, rather than balanced, species-appropriate, meat-based nutrition. Predictably, this ill-advised “vegan” diet had caused the kitten to become critically ill.
On a fiber alone diet cats are known to lose weight, therefore a cat will sometimes require added vitamins and minerals to assist with their wellbeing.
Probotic daily fiber is a way of replenishing vitamins and minerals maintain overall health of the digestive tract if an animal in the case of a fussy eater or having digestive problems.