For those who may be interested, I have done a bit more looking into the butter worms. I have reached out to several sources on this, and while I haven't heard back from all of them, I'd like to share what I've learned.
One of the vendors I contacted confirmed that their information is from their worm supplier. I suspect this is the case for the bulk of the retailers due to the very similar presentation and since they have the exact same numbers. I have only been able to locate contact information for one exporter in Chile, though I'm not sure how many there are.
I have also contacted the researcher who wrote the article I shared a few days ago. I was able to ask him directly about his work, as well as the claims elsewhere on the internet. Butterworms were included in this study in part because of the lack of information available about them. The following is a summary of the explanation and information he shared with me.
There are factors relating to the technical aspect than can influence results some. There are a few ways to analyze samples, different tests that can be ordered and some labs are more proficient than others in running these analysis. Diet and age can also have some impact on the results. Unfortunately, there are no other sources sharing details of their procedures. I have made this request to the exporter and some vendors, but I'm not sure what to expect.
The analysis such as the ones we are used to seeing for bugs (moisture, fat, protein, fiber, ash) are the total components of the material being tested and should add to be close to 100%. The marketed values from any of the sites listed do not add up (58.54+5.21+16.2+1.04=80.99). Fiber is missing, but the fiber content (carbohydrates) of insects is a small component, not 20%.
Dr. Finke's study also employed tests for fatty acids. Another way to check fat content is the sum of these components. The study indicated roughly 25% of the sample content to be fatty acids, therefor total fat content is at least 25%.
The calcium level of the butterworms claims to be exceeding any other feeder insect, or comparable to BSFL depending on the site. To quote the study "The exoskeleton of most insects is primarily composed of protein and chitin, although some insects, including soldier fly larvae, have a mineralized exoskeleton that explains their high calcium content." Butterworms lack this.
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Keep in mind, this study is a publication from a peer-reviewed scientific journal. Perhaps this lends some credibility to challenge the 'common knowledge'. I am still waiting to hear from the other sources as well and I will share that information as well.
Personally, I see no reason not to feed the worms as treats or occasionally (and its great they last so long) but I don't consider them a good component the to regular diet. This of course, is with the current understanding of dietary needs. That too is subject to change in the light of new information.
This is a hobby filled with misleading information and inaccurate claims by many sources. After all its the same industry selling compact florescent UV lights, 'calci-sand', crushed walnut shell and heat rocks, all legitimately dangerous products marketed directly at lizard owners.
