Hornworm misinformation

Squalt

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It seems to be a often repeated rumor that hornworms are fatty and therefore should only be used as treats for your T's and other pets. This however is incorrect, in fact hornworms have one of the lowest fat contents of the common feeder insects at 3%. It should be taken into consideration that they also have very low protein content and high calcium levels, as well as very high moisture, so by no means are they the optimal feeder.
 

boina

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Here is a wonderful graphic that lists the the main feeders and their compositions, very helpful!
https://blog.homesalive.ca/reptile-feeder-insect-nutritional-breakdown
Well, that's about half right... Feeder composition varies according to what they are fed themselves.

Further, did you look at that table? Butterworms only add up to 80%, mealworms to about 90%, so what else is in there? And the even better question: how does the silkworm manage to contain 157% of stuff??

I'll take it back: that table is not even half right, it's at least 75% nonsense.
 

EulersK

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@boina beat me to it :p

Gotta say though, never heard of hornworms being bad for tarantulas or any other invert. Quite the contrary, it's like a super food in terms of hydration. I pick those up for T's recovering from an injury or ones that need fluids immediately.
 

The Seraph

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Well, that's about half right... Feeder composition varies according to what they are fed themselves.

Further, did you look at that table? Butterworms only add up to 80%, mealworms to about 90%, so what else is in there? And the even better question: how does the silkworm manage to contain 157% of stuff??

I'll take it back: that table is not even half right, it's at least 75% nonsense.
Not to mention calcium is apparently not in percentages. I do not understand why they did percentages for everything else but calcium.
 

chanda

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And just in case anyone sees this thread and thinks feeding off the horde of hungry hornworms devouring their tomato plants is a good idea - it isn't.

While captive raised hornworms who are raised as feeders and fed a special diet make great feeders or treats for your pets, wild hornworms plucked from the yard or garden are chock-full o' toxins. They eat poisonous plants in nature (things like tomatoes, tobacco, jimson weed, datura, nightshade, and things of that nature) and squester the toxins in their own bodies as a defensive measure, making them generally unpalatable to birds or other potential predators.

(This is on top of the more general risks of pesticide exposure or parasites that accompany the use of any wild-caught feeders.)

Further, did you look at that table? Butterworms only add up to 80%, mealworms to about 90%, so what else is in there? And the even better question: how does the silkworm manage to contain 157% of stuff??

I'll take it back: that table is not even half right, it's at least 75% nonsense.
The chart and accompanying information is poorly worded, but I believe what they're trying to do is label each food item the way a bottle of vitamins is labeled. If you look at a multivitamin, it may contain 100% or more of each of a number of vitamins, indicating that each pill meets or exceeds the daily nutritional requirements of the average person for each of those nutrients. With this chart, I don't think it's trying to indicate what percentage of the worm is made up of fat, protein, water, etc. - but what percentage of the requirement of that item is in it. So when it says 3% fat for hornworms, it is not saying that 3% of the hornworm is made of fat, but that the average hornworm meets 3% of the fat intake requirements of whatever creature they made that chart for.

Of course, the chart does not specify for which animal(s) they used the nutritional information. Since every animal will have different nutritional requirements, and many will even have different requirements at different stages of development, the chart is still pretty useless!

At best, assuming some semblance of accuracy from the "external laboratories" they obtained the nutritional information from, it gives a relative proportion of protein, fat, moisture, etc. across various feeders. While the individual percentages may be somewhat meaningless, the notion that waxworms contain more fat than hornworms, or silkworms contain more protein than hornworms, may be valid - if they used animals with similar nutritional requirements across all types of feeders.

On the other hand, they could just be comparing apples to oranges if they used the nutritional needs of different animals with vastly different requirements for each of the listed feeders. For example, a feeder with a relatively low protein content may still meet a high percentage of the nutritional needs for an animal with low protein intake requirements, earning it a high percentage value, while a feeder with a high protein content may meet a much lower percentage of the total protein needs for an animal with a much higher protein intake requirement, earning it a much lower percentage value on the chart, even though it might actually contain significantly more protein than the first hypothetical feeder which earned a higher percentage value.
 
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cold blood

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All this nutritional value stuff you read about is primarily regarding feeding reptiles, which do have specific nutritional needs....needs a t does not have.

I honestly laugh when i hear people talking about t feeders nutritional values with concern or percieved "expertise" (comment not directed at anyone, just in general).

We know for a fact that one can feed a t crickets only its entire life...or mealworms...and live a long healthy productive life of breeding.

Feeding different feeders is great, most of us do this, but its not a necessity to a tarantula like it is for "higher" life forms.

People worry too much about their t feeders.
 

Vanessa

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I would consider them dense, due to their size and lack of any 'waste' components like crickets have, but not fatty. I have fed them in the past and they are great to use to put on some weight, but they also fill up tarantulas very quickly. I would definitely consider feeding them to a tarantula who needs to put on some weight, but they are just too cost prohibitive to feed all the time once you have more than a handful of spiders.
 

REEFSPIDER

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never heard that.

they make for great feeders for large arboreals. especially post molt.
My s.gigantea uses her hornworms like a paintbrush

I would say they're fine in moderation, i wouldn't feed them everyday but i like giving them to my pedes in premolt to give them a moisture/calcium boost going into the molt. But imo m.sexta is more enjoyable if you don't feed them, allow them to pupate, and then you get to feed them nectar and watch them lay a ton of eggs. I recently did this for the first time from purchased feeder horn worm, to pupae, to moth, to eggs, to worms again. I would have kept continuously rearing them but i dont need that many feeder hornworms, and its alot of work tending to 2 dozen or more adult moths.
 
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ErinM31

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It seems to be a often repeated rumor that hornworms are fatty and therefore should only be used as treats for your T's and other pets. This however is incorrect, in fact hornworms have one of the lowest fat contents of the common feeder insects at 3%. It should be taken into consideration that they also have very low protein content and high calcium levels, as well as very high moisture, so by no means are they the optimal feeder.
I believe that hornworms are only listed as high in calcium because the artificial diets they are raised on are high in this for the benefit of reptiles eating them.

I recently got a few dozen and am going to try keeping and raising them on a diet of various produce and either some ore made diet or something I concoct myself depending on how adventurous I feel and what works. :)

Hornworms seem to elicit a good feeding response; they don’t freeze or burrow (not counting those about to pupate), probably because in the wild they’re too toxic to have had to evolve additional defenses against predation.
 

Phia

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I personally can't stand the way worms move, so I don't feed them to my Ts. But this thread had some good info! I'll pick some up if I feel like a T needs emergency hydration !
 

Vanisher

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One of my friends is Swedens most respected arachnologist. She has among other things made experiments involving Wolfspider spiderlings. Their growthrate and mortality percentig in conjunction to diffrent types of feeders. It turned out that they where healthier, had increased survival rates and also the fertilety percentig in adult females where increased, when a group of spiderlings was given a diverse insect diet VS the group that didnt get this diverse insect diet. I dont know about tarantulas but in wolfspiders it had importance.
 

MetalMan2004

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One of my friends is Swedens most respected arachnologist. She has among other things made experiments involving Wolfspider spiderlings. Their growthrate and mortality percentig in conjunction to diffrent types of feeders. It turned out that they where healthier, had increased survival rates and also the fertilety percentig in adult females where increased, when a group of spiderlings was given a diverse insect diet VS the group that didnt get this diverse insect diet. I dont know about tarantulas but in wolfspiders it had importance.
I’d like to see the study instead of just taking your word for it, but that’s certainly “food for thought.”
 

Vanisher

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She told me about her resarch, so i just wrote what she said, but i have no reason to doubt her! I can ask her if she can publish it?
 

StampFan

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It seems to be a often repeated rumor that hornworms are fatty and therefore should only be used as treats for your T's and other pets. This however is incorrect, in fact hornworms have one of the lowest fat contents of the common feeder insects at 3%. It should be taken into consideration that they also have very low protein content and high calcium levels, as well as very high moisture, so by no means are they the optimal feeder.
You read this crap with waxworms too...."too fatty". Too fatty for who? Are inverts on Weight Watchers and counting points? Anthropomorphism at its worst.
 
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