Article on Fiber versus starch heavy diet

Interesting article:

Starch and fiber intake effects on energy metabolism, growth, and carapacial scute pyramiding of red-footed tortoise hatchlings (Chelonoidis carbonaria)

I thought I'd share it...

Jamie

I know this is from a year ago, but this is a very interesting paper for several different reasons. I'm wondering if @Kapidolo Farms has read this.

2turtletom said:

I know this is from a year ago, but this is a very interesting paper for several different reasons. I'm wondering if @Kapidolo Farms has read this.

Click to expand...

Thanks for putting my name here to draw attention. I'll read in the next few days.

let me save your time
on page 4 under 2.3.3 .
quote " Humidity was kept between 50 and 80%,"

i dont have to read the rest of the paper and i already know all of them got pyramiding regardless of diet
what a waste of time and funding

enchilada said:

let me save your time
on page 4 under 2.3.3 .
quote " Humidity was kept between 50 and 80%,"

i dont have to read the rest of the paper and i already know all of them got pyramiding regardless of diet
what a waste of time and funding

Click to expand...

So unfortunately, that would be ignorant, no offense implied, because it's packed full of interesting information about tortoise nutrition- Pyramiding is one aspect that they looked at as a result of high fiber diets or high starch diets, but there were many other things they also examined, and I myself need someone with more knowledge and experience to really understand some of their findings. And honestly, I think you'll find that at those relative humidifies during the day, you can grow a perfectly smooth shelled tortoise as long as there is a significant night time drop. With closed chambers, we know now how we can grow a smooth tortoise - but what is the low end that we can work with, regarding relative humidity, and still get nice smooth shells.

They kept both groups with the same humidity, 50% to 80%, so both groups pyramided equally. That fits what we already know on this forum about low humidity causing pyramiding. What was interesting in this study was the finding that high starch diet group seemed to cause growth about 10% faster, and also have about 10% lower bone mineralization, than the high fibre group. This was probably because the faster growth rate needed more calcium, so maybe calcium supplementation could prevent the lower bone mineralization from faster growth. Providing supplemental calcium is already part of good husbandry though.

GardiendeKoopa said:

They kept both groups with the same humidity, 50% to 80%, so both groups pyramided equally. That fits what we already know on this forum about low humidity causing pyramiding. What was interesting in this study was the finding that high starch diet group seemed to cause growth about 10% faster, and also have about 10% lower bone mineralization, than the high fibre group. This was probably because the faster growth rate needed more calcium, so maybe calcium supplementation could prevent the lower bone mineralization from faster growth. Providing supplemental calcium is already part of good husbandry though.

Click to expand...

I'm really grateful you posted to this thread and that brought it to the top on 'new posts'. I never read it before.
The article is very academically jargon rich, which makes reading it tedious. Congratulations on getting through it. They also seemed to have overlooked detailed studies of earlier work on natural and confined space in-situ food choices and the effect on tortoise food choices.

It's a common practice in academic studies to use methods with a huge footprint in past literature which had initially been developed for one set of circumstances, and then miss-apply it when the circumstances have changed. Im talking about how fiber measurements are made. Tortoise digestion has some big differences compared to mammal (human) digestion. From google AI search "Fiber in foods is primarily measured using laboratory enzymatic-gravimetric methods, which simulate human digestion to break down digestible starch and protein, leaving behind only the indigestible fiber to be dried, weighed, and analyzed. These methods, often standardized by AOAC International, allow manufacturers to quantify total fiber for nutritional labels. [1, 2, 3, 4, 5]". Based on the prompt "how is fiber measured for foods".

They used a standard definition of fiber which, IMO, does not fit tortoise digestion physiology. By extruding pellets through a machine to make the diets more uniform except the one variables of focus they somewhat lost much of how fiber has been demonstrated to impact the gut microbiome, digestion transit time, and nutrient absorption. Extrusion also 'cooks' the food with heat friction created by extrusion.

I think it would have been a simple thing to offer additional mineral resources to both group ad libitum (as much as they want) and then also measure that consumption.

enchilada said:

let me save your time
on page 4 under 2.3.3 .
quote " Humidity was kept between 50 and 80%,"

i dont have to read the rest of the paper and i already know all of them got pyramiding regardless of diet
what a waste of time and funding

Click to expand...

Reading for and/or using a 'red flag' aspect found in this studies denies what value can be had. I had a similar reaction, but I sorted expected to read that they all pyramided before I got to that part of the paper. I too, found many red flags. Maybe this is just a time waste reading I can get along with?

Noting the rest of the husbandry conditions, in this study they added vitamin D supplement plus gave the tortoises at least 2 hours of direct sun at least 3 times per week to avoid vitamin D deficiency, and did not use UV indoor lights. Both diets had 1.1% calcium and 0.7% phosphorus, which seems lower than the 2:1 ratio I’ve seen recommended, and could be a contributor to why the bone mineralization wasn’t able to keep up with the faster growth high starch diet. They used electric heaters or infrared lamps to keep temperatures at least 20C.