Venom404

Leiurus quinquestriatus (H. et Ehrenberg, 1829)
● Death stalker scorpion ●
Afrique du Nord, Sahara, Soudan, Egypte, Arabie et Israël

Effect of scorpion Leiurus quinquestriatus (H&E) venom on rat's heart rate and blood pressure.
The effects of scorpion Leiurus quinquestriatus (H&E) venom collected from the South Sinai region, Egypt, on heart rate (HR) and mean arterial pressure (MAP) were studied after intramuscular administration of 3 different doses (100, 200 and 400 micrograms/kg) to anesthetized rats. The effects of adrenergic and cholinergic blocking agents on the venom-induced HR and MAP changes were also evaluated. In two groups of rats, propranolol or atropine were given before the venom administration. In the third group the venom was given before the injection of propranolol and atropine in combination. HR was measured by using a cardiotachometer coupler connected to an ECG coupler. MAP was calculated from the recorded arterial blood pressure (ABP) after catheterization of the left common carotid artery. Venom doses of 100 and 200 micrograms/kg produced tachycardia with a dose-response relationship, whereas 400 micrograms/kg evoked sinus tachycardia followed by bradycardia then tachycardia. MAP was elevated after the administration of each dose and reached its maximum value after 60 min with a dose-response relationship. Sinus, atrial and ventricular arrhythmias were observed from the recorded ECG during the time studied. This study revealed that the venom has pressor and depressor effects which are mediated through the autonomic nervous system. Propranolol reduced the stimulatory effects of the highest dose of the venom while atropine was effective in eliminating the depressor effect of the venom on HR. The arrhythmias induced by the venom were blocked by the injection of the two blockers and are assumed to be due to the release of catecholamines and acetylcholine.

source: http://grande.nal.usda.gov/ibids/index.php?mode2=detail&origin=ibids_references&therow=165376

Demensia sp. est un Elapidae australien, sur lequel les scientifiques et les manuels s'accordent à affirmer la faible toxicité de son venin.
Comparable à une morsure d'Ahaetulla (Colubridae opisthoglyphe) ou tout simplement à une piqure d'abeille, la morsure de Demensia sp. a pourtant été recement mise en cause dans un décès.
Voici le texte original:


" 'Harmless' Snake Proves Deadly (Whip Snake, Australia) theage.com.au by, Dan Harrison, April 16, 2007

Friends of a reptile enthusiast who died after being bitten by a snake have expressed their shock that a man who knew snakes so well had been killed by a species generally regarded as harmless.

Ron Siggins, 37, of Pascoe Vale, died yesterday afternoon after being bitten by a whip snake at Harcourt North, 120km north west of Melbourne.

Mr Siggins was collecting scorpions with a friend at Mt Alexander about 2.30 pm when he was bitten on the finger by the snake.

He bandaged his finger with a handkerchief, but later became woozy and his friend went to his car to call an ambulance.

When the friend returned a few minutes later, the 37-year-old had collapsed.

Mr Siggins had gone into cardio arrest by the time paramedics arrived. They were unable to revive him.

Police will prepare a report for the coroner in relation to the man's death.
Mr Siggins caught the snake that had bitten Mr Siggins.

Bite 'like a bee sting'

The snake was later identified as a whip snake, a species which is considered harmless in comparison to more venomous species such as brown snakes and tiger snakes.

"You read any reptile book, they're classified as harmless, it's like a bee sting,'' said Steve Macgregor, a reptile enthusiast and friend of Mr Siggins.

While the exact circumstances of Mr Siggins' death remain unclear, it is believed he may have experienced complications as a result of medication he was taking for neck and spinal injuries.

Friends said he had been bitten by whip snakes in the past.

"Probably what happened is he knows they're not that deadly, he's been bitten by it and didn't think much of it,'' Mr Macgregor said.

Community 'devastated'

Another friend, Sheryl Longstaff, said Victoria's community of herpetologists could not believe what had happened to Mr Siggins, who had been around snakes for 30 years.

"It's a shock to the system ... everybody's devastated,'' she told theage.com.au.

"Ron's got venomous and non-venomous snakes at home, he knows what he's doing, he knows how to handle them,'' she said.

"He's got bitten by something that would normally just make you feel a bit sick and give you a bit of a headache but he's had a reaction to it.''

Mr Siggins leaves behind a wife, Helen, and school age daughters Emily and Stephanie.

Ms Longstaff said the community of reptile enthusiasts would rally around Mrs Siggins and the children.

"She's going to need a lot of help. She's got a lot of grieving to go through,'' she said.

Snake catcher Raymond Hoser said people should not fear snakes.

"All the deaths from snake bite in Australia in the past year have actually been people catching them or killing them," he said.
Provided you do neither of the above, you've got basically no chance of dying from snake bite.''

I recently received a very disturbing bite report (Poecilotheria striata) that was much worse than others I had ever heard before. Previously I'd expressed the opinion that warnings about Poecilotheria bites were overstated - I've changed my mind.

I was bit by a 5"+ Mysore Ornamental while I was taking some of the substrate
out of the jar I was temporarily keeping it in (around 5pm). I accidentally
touched its leg and she ran straight to the top of the jar. I quickly tried
to cover the jar with my hand but like all Poecilotheria species she was so
fast she ran onto my hand and the second she got on my hand she sunk her
fangs in-on the top of my left hand right my pointer and middle knuckle. She
stayed on my hand for about 15-20 seconds then I flung her off my hand back
into the jar. The bite felt like a bee sting but about 50X worse. About 20
minutes later my hand swelled up twice its size but the pain wasn't that bad.
Half an hour after that I started to get an immense burning feeling in the
top of my hand and in the middle of my palm but the swelling started to go
down. As time went by the pain traveled to my fingers and into my wrist and
I had a tingling/painful stream going straight up my arm going into my chest.
I started to get really tired and almost passed out but I kept myself awake.
About 5 hours after I was bitten the pain in my hand became unbearable. It
felt like I had a red hot knife going straight through the middle of my hand
and my fingers felt like they were smashed with hammers. I took benadryl
among other things so I could try to sleep through the pain. The pain was so
intense that it wouldn't let me sleep. I finally passed out around 7 in the
morning. When I woke up around 1pm the pain was easily ignorable so I
thought the worst was over. About 5 hours later I was at work and my legs
started to get sore. After a while all my muscles got sore and I was walking
like I was 95 years old and I started getting minor cramps in my calves. I
got home about 9pm and went straight to bed. Shortly after I started getting
cramps in my feet that were ridiculously painful and the joints in my hands
and knees were sore. The rest of the night I would wake up to these painful
cramps taking turns in all my muscles up and down my body from my feet
muscles straight up to my jaw muscles (every single muscle in my body went
through these cramps-I'm not exaggerating). My jaw muscles clenched shut and
I couldn't open my mouth for about 10 minutes. Around 11am the next morning
I was paralyzed for about 2+ hours. Any time I would move any part of my
body it would immediately cramp up. Once the cramps stopped I could hardly
move because my muscles were so sore and if I moved my arms, legs, feet... in
certain directions they would cramp so I had to move carefully. By that
night I was still getting cramps but they weren't as painful or frequent.
For the next two weeks I was still getting cramps in my legs and pain in my
hands and joints. I also noticed that I lost some muscle mass in my chest.
Then I woke up and my left shoulder joint was in intense pain. After two
weeks of still having symptoms from the bite and the feeling that I was
melting away and now with this pain in my shoulder I decided to go to the
doctor. I happen to know a Doctor from India (where the Mysore Ornamental is
from) who worked in India and treated many tarantula and snake bites. He put
me on steroids and pain killers and ran a bunch of blood tests. This
happened in the beginning August and now I am fine but occasionally get
cramps in my legs and hands.

Josh Peacock <IIIVeNoMouSIII@aol.com>


source: http://www.bighairyspiders.com/poec.html

Ordnung: Squamata
Unterordnung: Serpentes
Überfamilie: Colubroidea
Familie: Elapidae
Gattung: Hemachatus
Art: Hemachatus haemachatus

Republik Südafrika, Simbabwe, Lesotho, Swaziland.


source de la photo: repti.net

Synonymes : Boa de Cook, Corallus enydris, Amazon Tree Boa

Cites : annexe 2

Répartition : Amazonie, Brésil, Vénézuela, Nicaragua, Bolivie

non venimeux