The Difference Between Regurgitation and Vomiting in Snakes

Yeah, yeah, you all think I’m dealing with semantics here…but the words “regurgitation” (or regurge at it is wont to be called on the forums) and vomiting mean two very different things.

Short explanation: A regurge is the backflow of [I]undigested[/I] food (food that has never reached the snake’s stomach) up through the esophagus and out of the mouth. Vomiting is the forceful ejection of stomach contents through the same path of travel.

Long explanation and why it is important to differentiate between the two events:

A regurgitation most often occurs for reasons unrelated to health. A snake that has recently swallowed a meal may regurgitate it if stressed or annoyed in order to save the energy expenditure of digesting the food in favor of using it to escape. Many species of snake become vulnerable when digesting a meal, so the regurgitation of a prey item can allow it to gain an advantage in a fight or flight situation. The act of regurgitation does not carry a stiff health penalty, as digestion has not really begun and damage to the esophagus and gastric mucosa is unlikely.

On the other hand, an animal that vomits up a prey item days after ingestion often times has an underlying ailment. The inability to digest a prey item can indicate problems with the stomach, the kidney, the liver, the gall bladder or any other components of the digestive system. The problem can range from something benign (like improper husbandry) to dysfunction of the aforementioned organs, to internal parasites, viral or bacterial diseases.

Even in the case of a regurgitation, care should be taken in reintroducing food items. Snakes begin processing prey items fairly quickly so it’s always a good idea to wait the requisite two weeks before feeding again. As the vast majority of captive snakes are overfed anyway, missing a couple of meals isn’t going to compromise the health of an otherwise healthy animal.

In the case of a vomiting episode, not only should a minimum of two weeks pass before offering food,the keeper needs to keep an eye out for other signs of disease. Is the snake behaving normally or is it listless? Does it look dehydrated? Is it showing signs of discomfort (covered under a separate post)? If so, the animal should be taken in to see a qualified reptile veterinarian.

After a regurgitation or vomiting event, it is also a good idea to add Benebac or Reptibac to the animal’s water. These supplements help restore the beneficial bacteria present in the animal’s digestive system.

Prey Model Diets for Snakes – Clelia and Boiruna

I’ve touched on the fact that we not only overfeed our snakes, we also feed them prey that they do not predominately feed on in the wild.

This has led to keepers losing their animals at an early age.  As “mussurana” of various species are finding their way into more and more homes, I’m hearing more and more stories of these animals just dropping dead.

Most of the time, the keeper does not bother with a necropsy.  However, I’ve talked to a few hobbyists who have.  Some of these animals are dying of fatty liver disease and other “lifestyle” diet choices – and doing so at a fairly young age.

In 2002 a study was done by Carla da Costa Pinto and Thales de Lema regarding the feeding behavior of Boiruna and Clelia species.  This study covered many things:  differences in how they subdue and consume various prey types, their diet preferences and the size of their prey.

At this point in time, I’m only going to focus on what they eat, not how.

The study showed that mussurana have a varied diet – a whopping 23 food items.  They included the following snakes and lizards:

Liophis Almadensis

Lystrophis Dorbignyi

Oxyrhopus Petola

Sibynomorphus Mikanii

Thammodynastes Spp

Philodryas Patagoniensis

Oxyrhopus Rhombifer

Echinanthera Cyanopleura

Liophis Miliaris

Bothrops Jararaca

Mabuya So,

Ameiva Ameiva

Tropidurus Torquatus

…with the additional of the following birds:

Gallus Gallus

…and the following mammals:

Akodon Serrensis

Oryzomys Nigripes

Metachirus Nudiancaudatus

The predominant prey type being other snakes.  The inclusion of gallus gallus being a nod to these animals sometimes encroaching into human settlements and preying on chickens and chicks.

In the most commonly captive kept mussurana (Boiruna Maculata), the predation of mammalian species was observed to be purely opportunistic.  In an “emerging” species tot he hobby (Clelia Rustica), rodents were observed to be a targeted and selected prey item.

What does all this mean?

Short answer, we are feeding these animals the wrong diet.

Long answer:

An adult rat has the following proximate composition and energy content:

Crude Protein:    61.8%

Crude Fat:   32,6%

Gross Energy:  6.37 kcal/g

An adult rattlesnake has the following proximate composition and energy content:

Crude Protein:  60.6%

Crude Fat:  3%

Gross Energy:  6.51 kcal/g

Bottom line – much less crude fat, similar protein and similar energy.  We are forcing more fat into these animals than they have evolved to handle….and it is affecting their health.

With house geckoes and anoles being sold via online vendors as prey items, along with availability of inexpensive sources of corn snakes and juvenile boids, a variety of more suitable prey model-appropriate diets are available for clelia and boiruna.

I would argue that there is a viable market for providing feeder snakes to drymarchon, clelia, boiruna and other ophiophagus snake species.

In the long run, filling this market niche – providing proper prey model diets for snake eating snakes – will not only make us better keepers, but will make our captive charges healthier.

Re-Thinking the Whole “Rack” Thing…..

In general I feel like I’m a pretty decisive person…once I make a decision I tend to stick with it unless it just doesn’t make a whole hell of a lot of sense anymore.

When it comes to housing reptiles, I’m just the opposite.  I can’t count the number of racks and enclosures I’ve bought and sold as I’ve gone back and forth between housing options.

Except for some species that just can’t be kept in rack – varanids and arboreal snake species for example – I’ve pretty much converted all of my animals to racks.

From the ubiquitous V70/CB70 rack to the monster 66″ Freedom Breeders, the snake house is chock full of racks.

But as I get older and observe my animals more, the more I’m convinced that they would are more comfortable in specialized enclosures.

I converted all my drymarchon to 60″x24″x24″ enclosures.  Each one sits atop a shelf that holds a cement mixing tub.  The enclosure has a hole in the floor that leads the the mixing tub, effectively creating a tidy little dark and cool burrow.

I am now in the process of converting all my clelia, pituophis, terrestrial philodryas and psammophiidae to similar enclosures, with my heloderma to follow.

Now don’t get me wrong, there is nothing wrong with a rack properly sized for the target species.

However, I just enjoy watching my animals in larger enclosures…and in the end, maybe I’ll be the only one getting any benefit from it.  I also find it easier to customize husbandry parameters for each species in a larger cage.  In a rack, you tend to shoot for a happy medium when housing several species.  In a cage, the options are limited only by your capacity to create them.

…and I’m pretty sure none of the animals will be the worse for the change…once they acclimate.

The bad news – a whole lotta cage building, staining and running back and forth to the hardware store and the lumber yard.

The good news – some people in the Bay Area are going to get some smoking deals on some beautiful Freedom Breeder racks.

Inbreeding in Nature

So I’ve been reading some discussions on other sites and had a bit of an epiphany…a lot of people are talking about inbreeding.

Inbreeding clelia and health issues, inbreeding Drymarchon and health issues, and so on and so on.

People are talking about the limited captive gene pool and how it needs to be diversified for many species.

Now, with the exception of some select species, snakes are fairly limited in their roamings and wanderings. That’s sort of how locality variants are formed – as well as intergrades. Gopher snakes in Contra Costa County have subtle differences compared to those in Alameda County. Some pituophis vary within localities.

We also know this to be true for various thamnophis and lampropeltis.

Which brings us back to inbreeding. Let’s say the wandering range of a female gopher snake in Northern California is about 30 acres and about 4 times that for a male….just how many gopher snakes can 120 acres support?

Again, science is our friend. Studies have shown that there are an average of 1.3 gophers snakes per 1/2 acre, which means that in 120 suitable acres, you could expect to find 312 gopher snakes.

Now within that 120 acres, there is bound to be overlap with other wandering ranges, but also keep in mind that not all habitat is suitable for supporting these animals.

Bottom line – in nature, there is also a self limiting gene pool with specialized species. Mother and fathers breed with sons and daughters, grandsons and granddaughters. There is inbreeding and line breeding going on in the wild.

The difference is nature culls without pity or sentiment. Animals with genetic deformities do not survive to breed. Only the strongest and fittest (and admittedly inbred) snakes earn that right.

That’s where our flaws lie. Aesthetics often preclude soundness. We propagate traits that, while aesthetically pleasing, do not result in strongest and most healthy animals.

We also overfeed our animals and while we apparently have gotten on board with feeding our dogs and cats appropriate prey model diets, we insist that reptile eating snakes can survive on a mammalian diet without any ill effects.

The long and the short of it is this…inbreeding happens in the wild. Bemoaning the practice of doing it in captive animals is disingenuous.

The practice of feeding too much food, too much of the wrong food and selecting animals for aesthetics is compromising captive populations….not “inbreeding”.