Is fiber still the same if its source is powdered?

If I turn the source of fiber into powder then consume it, will it be as beneficial? Or does the texture play a role somehow? I’m asking for my pets but it’s probably the same answer. I have small tortoises and their diet requires high amounts of fiber. It needs to come from grass but they don’t like to eat it. So I thought of powdering hay and mixing it with foods they like. Such that they still consume the same amount of grass just in powder form.

Answer

Fiber is divided to soluble and insoluble one. Soluble fiber is food for the gut microbiome, which then provides fatty acids and CO2. Insoluble fiber works on a physical layer absorbing liquids and clumping up the fecal mass and as a result making defecation easier. Powdering breaks the insoluble fibers down way too much, it’s efficiency lowers with lowering the size. But it doesn’t really affect the soluble fibers because the bacteria don’t care what size of a fiber to eat.

That’s being said, tortoises and humans are significantly different. Some of the fibers that are insoluble for us may be actually digested by the tortoises microbiome (think of how cows and other cattle can digest grass while we can’t). So it’s hard to answer your question from the humans perspectiveOne needs to understand what the fiber is for in the tortoise’s body. It’s probably better to ask in a tortoise-themed subreddit.

Answer

I’ve got no experience with tortoises, but I have to wonder what animal (besides humans) won’t eat their natural diet when given freely without the need to even hunt or gather it. Are you sure your tortoises actually eat what you are trying to give them?