Home >> Reptiles >> Snake >> Venomoids - A Practitioner's View
Venomoids - A Practitioner's View
Reproduced with permission of Raymond Hoser
Originally published in The Herptile 29: March 2004, pages 36-52 including numerous photographs.
In other words these people wanted to have their cake and eat it too.
Whilst in the past it was easy to tell these people to simply accept the possibility of a snakebite risk, recent events here in Australia were changing things.
In the 1990's a respected (but then young) keeper Aaron Briggs from Coburg, (Melbourne, Australia) was bitten by a pet Death Adder (Acanthophis antarcticus). That in itself wasn't too exceptional, but for the fact that it was a quiet news day and the local news media got onto the story. Within days the "do gooders" were demanding that reptile keeping be outlawed and the herpetological community had to fight a rearguard action to preserve our hard won rights. Ultimately, the keeping of venomous snakes was made more restrictive (including outlawed to under 1, but no other rights were lost.
Just prior to doing a snake show in 2001, Fred Rossignolli was bitten by a large King Brown Snake (Cannia australis). Instead of doing a snake show, he landed at the Maroondah District Hospital and again there were calls to outlaw the keeping and displaying of venomous snakes. Those calls blew over and nothing significant changed, but it was a wake-up call to those who keep or handle deadly snakes. Regulation of exhibitors did however tighten up to include the need for more secure (lockable) cages/containers, warning labels and the like.
In the 2002 Melbourne Agricultural Show, Workcover officials whinged at Fred Rossignolli for walking barefoot in his pit full of dangerously venomous snakes. Fred wasn't allowed to show snakes at the 2003 show, even though his show was generally regarded as "the best" and no incidents occurred the previous year (bearing in mind Fred does such shows daily and has only been bitten once in ten years doing such shows).
Yes, he's had a few "food bites" at home, but that's another story.
Another snake handler, Simon Watharow, "stole" the Melbourne show gig from Rossignolli on the basis that his display was "safer", even though it was generally conceded that the entertainment value and educational benefit of the Watharow show was vastly inferior to Rossignolli's. (Rossignolli free handles his snakes, while Watharow uses pinning sticks and hooks only). In other words, there was a push from persons and organisations outside of myself for a safe alternative to educating the public with deadly snakes, with all the benefits of the handler being able to free handle snakes as needed, but at the same time to minimize the risks.
Internet forums are rife with comments about venomoid snakes (generally negative) and I am not going to add my own views to the already polarised views online already, save to dispel a few myths under the next heading and elsewhere in this paper. However, having been involved in snake science for more than 3 decades, I can assure readers that my own handling skills are sufficient to exclude the need for me to neuter the venom glands of snakes for my own ends.
MYTHS AND CORRECTIONS
Venomoid is the term used for snakes, which have had their venom glands removed and the name given to surgical procedures to do this.
From a practical point of view, snake venom is of no discernable benefit in terms of digesting food. This is evidenced by the fact that pre-killed food is digested just as easily (and rapidly) as food killed by snake venom. In other words any breakdown of tissues of prey by venom is of insignificant benefit in terms of aiding digestion, or being essential to it. Claims to the contrary have no substantive basis.
If contrary claims did have a factual basis, then it would not be possible to feed venomous snakes indefinitely on pre-killed food, or in the case of some Australian elapids, such as Tiger Snakes (Notechis scutatus) a diet of items as diverse as dead fish, steak, sausages, steak, pork, ham and Calamari (squid), all of which I have done. Similar applies for other elapids, fed nearly as varied diets, including Red-bellied Black Snakes (Pseudechis porphyriacus), Eastern Brown Snakes (Pseudonaja textilis), Small-eyed Snake (Rhinoplocephalus nigrescens), Death Adders (Acanthophis spp.) and others.
Removal of venom glands in other words is merely the neutering of the snake's ability to kill live prey. As the process is not reversible this means that the snake can (probably) not be fed live food again. In the captive situation of keepers like myself, this is of no relevance as food given to all snakes is dead and taken from a freezer. It does however mean that the snake cannot be released into the wild and expected to fend for itself. But the inability to immobilize live prey is the only measurable negative of venomoid surgery and in the real world of herp keepers is rarely an issue. Performed correctly, venomoid surgery is not particularly painful for the snake and recovery from the surgery is very rapid. This is amply demonstrated later in this paper.
As only non-essential soft tissue is excised, recovery speed is fast due to the fact that no bone or tooth repair is necessary and healing tissue is generally fixed (not moving) and not in use as would be the case for something like a limb in a human.
Snakes on which surgery is performed (properly) will often be willing and able to take food almost immediately after operation, as in taking food offered within days.
Complications from surgery in the form of injury, infection or arising from anesthesia in properly performed operations are almost unknown (and totally unknown in my own situation) and in the rare cases where they may arise, are (presumably) easily treated and dealt with. Venomoid surgery is not essential to snakes in that it is not necessary to save the snake's life. It is best classed as "elective surgery" and hence should only be undertaken on healthy well-adjusted snakes in circumstances where there is no known risk to the snake from such a procedure. It should be treated in much the same light as (sexually) neutering a dog or cat, although the latter operations have far greater long-term effects on the health and personality of the subject animals.
WHO SHOULD PERFORM VENOMOID SURGERY ON SNAKES
As a procedure it is remarkably simple and while it would be generally advised that a qualified veterinary surgeon perform the operation, this is not necessarily essential or for that matter the most important requirement.
What is more important (and far more so) is that the operation is only performed by a person experienced in performing such operations and who is familiar with the exact procedure to be followed in terms of what must be done. This experience can only be gained by doing such operations and should therefore be gained in the first instance by studying of appropriate dead snakes upon which the operation can be practiced as often as is necessary.
Anesthesia procedures used to neutralise the snake during the operation should be fully tested on appropriate snakes prior to doing a "real" operation, so that nothing is left to chance when the first operation on a live snake is performed. The operation should only be performed by a person familiar with the snake species to be operated on and who is skilled at handling the reptiles. Noting the pre-operational matters of sedation and after the operation itself, revival, it is essential that the operation be performed by a person who is skilled and experienced at handling the said species.
This paper explains a successful process used and refined, so that if and when others need to perform such surgery, that it can be done using proven and tested methods that will not adversely affect the snake(s) in question.
VENOMOID SURGERY
The species in question here to be "neutered" so to speak, were Tiger (Notechis scutatus), Eastern Brown (Pseudonaja textilis) and Copperhead (Austrelaps superbus). All are deadly venomous snakes and the first two account for the vast majority of fatal bites in Australia, including among keepers and non-keepers. The only record of venomoid surgery in Australia was the case published by Dave Millar in Herpetofauna in 1976. In that case involving two Tiger Snakes, he made an incision into the side of the head (from outside the head) and removed the gland immediately underneath.
Millar used various methods to immobilize the snakes during the procedure and for reasons unknown did two operations on each of two Tiger Snakes, removing one gland at a time.
For the first operations, the snakes were immobilized by cooling to a state or torpor and then by being held down at the relevant temperature were operated on. The snakes apparently healed well and both accepted food a week later.
In the second operations, to remove the second venom glands the snakes were immobilized with chloroform. This time the operations were not a success. One animal developed a series of (linked?) infections and died, while the other had a somewhat checkered road to recovery. It was presumed that the problems arose from the sedation process and not the surgery itself, but this isn't certain.
Either way, it is clear that the Millar operations were an abject failure.
While there are frequent claims made about venomoid surgery by reptile keepers, there has been no proper paper detailing a tried, tested and apparently risk-free procedure for doing the operation and so before commencing the first operation further research was required. Consultation with veterinary surgeons and the relevant texts (such as Fry 1991 and Mader 1996), revealed no shortage of ways to anesthetize snakes and immobilize them.
However a common complaint by various veterinary surgeons was the differential between snakes in terms of required dosage needed to immobilize the snakes, even of the same size and species.