RE: NANFA-L-- brindled madtom potency

Christopher Gutmann (cgutmann at dupageforest.com)
Tue, 27 Sep 2005 08:04:31 -0500

Mike,
Madtoms do not have an injection mechanism, per se, like vipers. The deliver mechanism for madtom venom is very simple. The venom is contained within an integumentary sheath. When you grab a madtom, the spine pokes through the sheath (and your skin), thereby releasing the venom. Because of the relatively passive delivery mechanism, if you get lightly jabbed, it is possible to get a "dry sting" where the sheath is not broken / your skin is not broken and venom is not released into you. That has happened to me. I did have a member of my field team get envenomated by a 3.5 - 4" brindled madtom. His experience was considerably worse than the one you described. He got hit in his finger (which turned bright purple), and he said it felt like someone had his finger over an open flame. The pain lasted two days. I suspect, though, that reactions to madtom venom vary between individuals. If you're interested, Birkhead published a study in the '70's on Ictalurid sting toxicity (includin
g some Noturus spp.), and Hugh Reed published a couple studies pertaining to the venom delivery mechanism of madtoms.

Chris Gutmann

-----Original Message-----
From: owner-nanfa-l at nanfa.org [owner-nanfa-l at nanfa.org]On Behalf
Of Mike Austin
Sent: Monday, September 26, 2005 7:41 PM
To: nanfa-l at nanfa.org
Subject: NANFA-L-- brindled madtom potency

On Sunday (9/25) I was seining just above a riffle on the Little Muskingum River where I was enlightened for the first time by a madtom. I have handled madtoms many times before without incident. In this instance I was sorting through my seine when I noticed a crayfish had clamped down on a brindled...I grabbed the crayfish and tried to shake the madtom free when I took a hit in the forefinger. The pain was instant as was a small speck of blood. It was not as bad as I thought it would be but it lasted a full 30 to 40 minutes. Turned slightly red and swelled. The swelling was not obvious but I could feel the swelling when I would make a fist.

I understand there is a venom gland at the base of the pectoral spine and there is a groove in the spine as well. Is the spine and fin continuously impregnated with the venom or is there a system in place as in a pit viper ....ie the gland is contracted and venom is sent through or along the groove (I guess in a pit viper it is a hollow fang..so maybe more like a rear-fanged snake or a gila monster)

Also, this particular individual was small (just over 2 inches)...can I assume a full fledged adult would be more painful..larger gland/larger spine etc.??

I collected 22 brindled madtoms in an area that was roughly 50' X 50'..in addition, a small mudpuppy about 2 inches in length as well. My daughter wanted to keep mudpuppy but I was not sure how they do in captivity.

thanks Mike
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