The Source of Vomiting in the Emerald Tree Boa (Corallus caninus)

(c) Graham P. Oxtoby 2007/2008 Journal of the British Herpetological Society 2008 

THE OCCURRENCE OF PSITTACOSIS IN THE 

EMERALD TREE BOA (CORALLUS CANINUS) OF 

SOUTH AMERICA 

GRAHAM P. OXTOBY 

[Abstract] 

Corallus caninus – the emerald tree boa of South America – is renowned for the many difficulties it may 

present whilst kept in captivity. The problems which may occur vary from stress-related symptoms and the 

refusal to feed and endoparasitic diseases (worm infestations and infections caused by flagellate colonies in 

the intestines), to the vomiting of prey, also known as ‘regurgitation’. 

Corallus caninus – the emerald tree boad of S. America (Photo by author). 

Swan & Weidner [2002] describe this chronic condition as the Emerald Vomiting Syndrome or EVS. This 

vomiting or regurgitation of prey has often been attributed to stress-related factors or imbalances between 

humidity and temperatures in the captive environment. As rightly pointed out in a publication by Swan & 

Weidner [2002], the term 'regurgitation' is perhaps not an appropriate way to describe these symptoms since 

regurgitation is usually referred to as a condition in which animals store food in a crop or in their esophagus 

for later retrieval in order to feed their offspring. This is seen, for example, in numerous species of bird. 

Vomiting, on the other hand, is a term generally used to describe the abrupt involuntary evacuation of the 

contents of the stomache after the break-down process of food mass in the stomache has begun, as is 

typically the case in specimens of Corallus caninus exhibiting symptoms the Emerald Vomiting Syndrome 

[EVS].


Causal factors of EVS 

Many claim that this syndrome – EVS - is generally 

caused by stress or in part by the imbalance of 

humidity and temperature in the captive environment 

of Corallus caninus. However, recent studies, amongst 

others by Swan & Weidner [2002], suggest that the 

symptoms are only manifest in captive specimens of 

the emerald tree boa that orginate from exporting 

locations where birds (in particular parrots) are kept 

for later exportation and introduction into the 

international pet trade. Swan & Weidner mention this 

in their paper [2002] in which they also describe 

situations in which this occurs. 

After conducting studies in captive caught specimens 

of Corallus caninus, Swan and Weidner [2002] suspect 

that the organism known as Chlamydophia psittaci is 

the cause of this condition. The authors also state that 

their findings are by no means based on true ‘scientific’ 

analysis or study. 

The same applies to this current paper. It is merely a 

collection and summary of data and information 

widely available in literature on this subject, but, at the 

same time, poses the important question regarding 

whether EVS is, in fact, a manifest form of Psittacosis 

in Corallus caninus, the emerald tree boa of S. 

America, or that regurgitation (EVS) can be attributed 

to a much wider spectrum of disorders (both phyisical 

and environmental) in Corallus caninus. 

The studies conducted by Swan & Weidner revealed 

that, whilst a certain percentage of specimens collected 

for the pet trade exhibited symptoms of Psittacosis 

(also known as the Parrot Disease), others did not. 

They attribute this to the fact that some wild-caught 

specimens of Corallus caninsus are housed in close 

proximity to numerous species of tropical bird, for 

example parrots, before being exported and introduced 

into the international pet trade. In their article, 

reference is made to a trapper who kept specimens of 

Corallus caninus segregated from avians whilst 

awaiting exportation and that it was found that the 

disease did not occur in those specimens. 

Specimens of Corallus caninus which were not housed 

in close proximity to birds whilst awaiting exportation, 

were not affected by this disease and did not exhibit 

the characteristic symptoms of Psittacosis or EVS. 

The disease was observed only in specimens that had 

been kept in close proximity to avians after capture. 

Other species susceptible to this disease include redtailed 

boa constrictors and anacondas collected for the 

pet trade. 

Further studies under clinically defined laboratory 

conditions with the use of sampled specimens will be 

required in order to assert these assumptions; these 

were conditions which could not be provided by Swan 

& Weidner [2002] at the time their own studies were 

undertaken. Even so, their claims may have great 

significance and therefore warrant further scientific 

investigation by specialists in this field. 

Psittacosis 

Psittacosis is a common and potentially serious disease 

occurring in avians, mammals and humans. The 

disease is not fully understood and there is still a lot to 

be learned about the condition. The causal organism, 

Chlamydia psittaci, has recently been renamed 

Chlamydophia psittaci and is found in a wide variety of 

(tropical) birds, but may also occur in mammals, 

including humans causing serious illness. 

This species of organism is now sub-divided into many 

subspecies, each affecting a different animal. For 

example, the type which will affect cats produces an 

eye-infection called conjunctivitis or blepharitis 

(inflammation/infection of the eyelids). In sheep, the 

disease is said to result in premature abortion and in 

humans, it has been established that this disease will 

most probbaly cause atypical pneumonia. The 

organism producing a genital/venereal disease in 

humans has now been classified as a separate genus: 

Chlamydia trachomatis. 

The generic term for the disease produced by 

Chlamydophia psittaci affecting all species – both avian 

and mammalian - is chlamydiosis. When this disease is 

exhibited in avians, it is called ornithosis. When 

exhibited specifically in psittacine birds, it is 

designated as psittacosis, a designation also used to 

describe the disease occurring in mammals, including 

humans. 

Fluorescent antibodies associated with infection by 

Chlamydia psittaci, 40X. Courtesy of Dr. Jean 

Sander & Merck Veterinary Manual 

The organism itself is unusual in that it possesses 

certain characteristics of both bacteria and viruses. It is 

relatively large and also highly sensitive to antibiotics. 

It resembles viruses in that it can only develop and


multiply within the cells of its host. The damage is 

caused by the rupture and further destruction of these 

cells and the release of toxins into the host’s biologic 

system. Chlamydia appear to infect and multiply in 

most cell-types, thus resulting in a widely variable 

disease pattern. 

Elementary bodies associated with infection of 

Chlamydia psittaci, 100X. Courtesy of Dr. Jean 

Sander & Merck Veterinary Manual 

In Corallus caninus, it is said to cause the destruction 

of HCl-producing cells needed for the break-down of 

food masses in the stomache. 

The organism is also able to survive outside the host 

for approximately one month if protected by cell 

debris and protein material (i.e. droppings, nasal 

discharge etc.). An important aspect of control of the 

disease is therefore cleanliness and disinfection to 

remove such debris from confinements in which the 

host animal is kept. 

Members of the Chlamydiaceae are so-called nomotile, 

gram-negative, obligate intracellular organisms that 

possess a unique developmental cycle consisting of 

metabolically inactive infectious elementary bodies 

(EBs) and metabolically active, but non-infectious 

reticulate bodies (RBs). Chlamydiae, on the other 

hand, replicate in the cytoplasm of host cells within an 

endosomalvacuole which appears under light 

microscopy as an intercellular inclusion (see image 

above). 

Chlamydophia psittaci is considered a dangerous 

organism to handle under laboratory conditions. For 

many years it was a major cause of laboratorycontracted 

infections. It generally resulted from 

exposure to and the use of aerosols. The stability of the 

organism in a laboratory environment is also 

considered to be a potential danger, also to humans. 

Disinfectants found to be highly effective against this 

organism include ammonium compounds, 

benzalkonium chloride and formaline-based 

compounds. The conventional fumigation of 

quarantine confinements with the use of formaldehyde 

gas (formalin and potassium permanganate) has 

proven to be highly effective against this organism, 

provided that surfaces have first been adequately 

cleaned [Jones, Alan K., ]. 

The natural occurrence of this infection is world-wide 

and it has been estimated that 1% of all wild birds are 

infected and therefore also act as carriers. Many avians 

can retain the organism in their bodies in a latent state 

without immediately showing signs of the disease - 

these birds are carriers and are a persistent risk to 

other birds and other animals susceptible to the 

disease. 

It appears that the infection or disease is most 

predominant when external stress-related factors 

occur, i.e. capture, loss of food sources, change of 

habitat, transportation, quarantine and relocation. The 

disease is therefore most commonly observed after 

recent capture, relocation and importation into the pet 

trade, particularly in avians. This is also the time when 

most wild caught animals are stressed, thus resulting in 

the weakening of their natural biologic resistance. 

This brings the current discussion to the points made 

by Swan & Weidner [2002], where the authors explain 

the dangers which may exist when other species are 

held in confinements in close proximity to infected 

avians in their countries of origin or during and after 

transit, such as is the case in wild-caught Corallus 

caninus (the emerald tree boa) collected in particular 

in Guyana, Surinam and other regions of S. America. 

These are regions where avians are also collected for 

exportation and introduction into the international pet 

trade. 

When kept in confinements awaiting further 

transportation, carriers of Chlamydophila produce 

droppings containing the organisms. Avians and other 

animals are often kept in close proximity with each 

other in these conditions and due to the extremely 

contagious nature of the disease are therefore highly 

susceptible to the organism and resulting infection. 

The disease may therefore spread very rapidly. 

Contracting is generally by airborne contact with 

inhaled fecal dust from dried feces or droppings. The 

incubation period (the time between the moment of 

contracting the organism to the manifestation of clear 

clinical signs) however, is extremely variable and can 

be confusing when attempts are made to determine the 

exact source and cause of the infection. 

The organism may also reside in the host in a latent 

state, only to be triggered at a later stage under stress-


related conditions (e.g. relocation, transport, new 

confinement) to produce clinical signs. In the latter 

case, the onset triggered by these stress factors and 

may therefore also occur long after the animals have 

been exported and been placed in their new homes 

(e.g. at the location of the new owner). 

The minimum incubation period documented to date 

is 10 days, although ongoing studies suggest that this 

period may vary from between 10-45 days. The 

maximum period may be from between 9-18 months 

when in its latent state, i.e. long after exportation of the 

animals to other countries and into the pet trade, or at 

the location of its new owner. 

This means that regulated quarantine periods have 

little or no bearing on the recognition of the infection 

or the time of onset of the infection. Animals may be 

infected by the organism, but show no clinical signs 

throughout prolonged periods of quarantine exceeding 

3-6 months. This also makes it very difficult to 

determine the actual source or time of the infection. 

Outbreaks of the disease may therefore occur in 

populations of apparently healthy animals that have 

previously shown no clinical signs of the disease for 

months or even years. From this, it follows that, 

contrary to popular belief, avians brought into a 

country and subjected to relatively long periods of 

quarantine (3-6 months) cannot be guaranteed to be 

free from psittacosis. In the UK, for example, the 

quarantine period for imported birds is 35 days, i.e. it 

ends 6-10 days before the probable maximum period 

of incubation of the organism is reached, not including 

those specimens in which the organism may reside in a 

latent state. In many countries therefore, regulated 

minimum periods of quarantine are most probably 

ineffective for the purpose of recognising the 

occurence of psittacosis. 

In an attempt to control psittacosis, in the US many 

quarantine stations administer the board-spectrum 

anitibiotic Tetracycline to avians during their stay. This 

is regulated by US law, but is not the case in many 

other countries such as the UK and other EU member 

states. Although some importers in the UK will 

administer Tetracycline as a preventive measure, they 

are not obliged to do so. In addition, the use of 

Tetracycline does not reliably eliminate the disease or 

further contaminations by the organism. 

Clinical signs of psittacosis 

Clinical signs are many and variable. They depend 

largely on the species involved. Some animals, like cats, 

are reported to develop serious eye infections like 

conjunctivitis or blepharitis (inflammation of the 

conjunctiva and swollen eye-lids). In avians and 

reptilians the symptoms most predominant are: loss of 

weight and appetite, diarrhoea, vomiting and 

sometimes respiratory symptoms. These are only the 

visible signs. 

The symptoms observed in EVD in Corallus caninus 

are very similar, but in EVS vomiting predominates 

(24-72 hours after ingestion of prey), together with the 

refusal to eat and gradual dehydration. There is also a 

marked weight loss due to continued or prolonged 

inappetance and vomiting after feeding and the wellbeing 

of the specimen affected rapidly diminishes. 

Proper clinical diagnosis of the disease is difficult since 

may of these same symptoms may also arise in 

reptilians as a result of stress and infections by other 

endoparasitic infections (including Cryptosporidiosis) 

and not all of these signs may be present at any one 

time. Systemic infections which may also produce 

many of the same symptoms include e.g. infections 

cause by flagellates and worms, the common cold in 

reptilians and the initial stages of secondary pneumonia 

resulting from loss of biologic resistance etc. which, in 

many cases, may be purely stress-related. 

As pointed out by Kolins & White: ‘The classic 

presentation of Cryptosporidium serpentis infection in 

the snake is an animal which regurgitates its meal 

within four days or less of ingestion. This regurgitation 

occurs because of decreased gastric lumen size and 

mucosal irritation. Since the diameter of the stomach 

has often increased, a noticeable swelling can be 

visualized and palpated in the mid-body region. The 

snake may or may not be anorexic, depending on how 

far the disease has progressed. Often, a mucoid 

diarrhea is noticed. 

It is important to differentiate Cryptosporidiosis from 

other causes of regurgitation and gastritis. Suboptimal 

temperatures, inappropriate prey size, stress, and 

foreign body obstructions are other potential causes of 

regurgitation. Hibernation associated necrotizing 

gastroenteritis, parasitism from other protozoa and 

nematodes, viruses, Salmonella and other bacteria can 

all cause similar signs, but the gastric swelling is 

pathognomonic for Cryptosporidiosis.’ 

From this, it follows that not all symptoms seen in 

psittacosis can be attributed to the presence of 

Chlamydophia psittaci, which makes any positive 

diagnosis based upon symptoms alone far from 

conclusive. Any accurate diagnosis must therefore be 

supported by further clinical laboratory tests, 

otherwise the assumption that these symptoms are 

caused by Chlamydophia psittaci may only be 

considered as speculative. In many cases, blood 

samples will only demonstrate antibodies, which only 

means that the reptile has been exposed to 

chlamydophila at some time. That in itself would


support the theory by Swan & Weidner [2002] that the 

organism must have been contracted during its stay in 

confinements in close proximity to avians before, 

during or after exportation. 

In order to be of any relevance, blood tests would need 

to be repeated 10-14 days later for the results to be 

suggestive of recent infection. The organism can be 

identified in blood samples only during the 

multiplication stage of the organism and because this 

period is only limited, negative results would not 

always implicate that the specimen does not have the 

disease. The most effective means of diagnosing the 

infection in Corallus caninus would be a post-mortem 

(autopsy) examination of the carcas or immediate 

examination and laboratory analysis based upon 

cultures of the organism collected from fresh feces or 

post-mortem material. 

Typical signs would be similar to those found in other 

septic infections: inflammation of the stomache and 

destruction of the stomache lining cell structures, 

enlargement of the spleen and liver and inflammation 

of the membranes of the air sacs, heart and 

peritoneum, i.e. the transparent membrane that lines 

the abdominal cavity. 

There are other tests available for detecting 

Chlamydophila antigen in feces, e.g. ELISA (Enzyme 

Linked Immunosorbent Assay), which provides 

quicker results on samples that contain the organism. 

Other tests developed for testing for the presence of 

this organism include Latex Agglutination (L.A. ) and 

Direct Flourescent Antibody (F.A. ). However, PCR 

technology using Chlamydophia psittaci- specific DNA 

probes has proven to be the most effective method of 

identification. 

Treatment 

The treatment of psittacosis may not be as simple as it 

may seem. The drug of choice in avians and reptilians 

is one of the Tetracycline group, to which the 

Chlamydial organism is sensitive. Doxycycline is a 

semi-synthetic tetracycline clinically developed in the 

early 1960s by Pfizer Inc. and also marketed under the 

brand name Vibramycin. Vibramycin received FDA 

approval in 1967, becoming Pfizer's first once-a-day 

broad-spectrum antibiotic. Other brand names 

include: Monodox, Periostat, Vibra-Tabs, Doryx, 

Vibrox, Adoxa, Doxyhexal and Atridox. 

The drug needs to be administered according to a 

regime which will produce an effective dose for a 

sufficient period of time. Provided that a precise 

diagnosis is made quickly enough, treatment with 

Tetracycline or Erythromycin will usually produce a 

rapid response, but not if the condition is diagnosed 

too late or mistaken for other conditions which exhibit 

similar symptoms, or if the infection has been present 

for a longer period of time. 

Erythromycin is a macrolide antibiotic that has an 

antimicrobial spectrum similar to or slightly wider 

than that of penicillin and has proven to be highly 

effective in the treatment of acute outbreaks of 

Chlamydia. 

According to Swan & Weidner [2002] 'The apparent 

successful dose used for gastric Chlamydophilal 

infection in emerald tree boas is 25mg/kg orally, daily 

for ten consecutive days. 

Treatment for shorter periods of 5-10 days will often 

produce a rapid clinical improvement, but the reptile 

will not be cured and relapses may occur. The 

antibiotic only acts on organisms when they are 

growing and multiplying, and since the Chlamydophia 

can exist dormant (i.e. in a latent state) in cells for 

some time, the drug will be useless during these 

periods of latency. 

Additionally, the prolonged use of antibiotic can itself 

pose problems of imbalance of the normal intestinal 

flora, producing diarrhoea and malabsorption 

conditions, or secondary infection by opportunist 

fungi or yeasts. There may also be some immunosuppressive 

effects to the drug and it can be difficult to 

maintain therapeutically effective levels of the 

tetracycline within the cells. Tetracycline also reacts 

with calcium in the diet to limit its absorption, so diets 

with high calcium levels in animals undergoing 

treatment with the drug should be avoided. 

Doxycycline is available as 'Vibramycin syrup' and is 

administered orally. This is probably preferable for 

single, handleable specimens of Corallus caninus. It 

may be administered by means of a catheter inserted 

into the esophagus. Since this technique involves 

handling and therefore stressing the reptile at regular 

intervals, this may sometimes be impractical since it 

may also contribute to additional stress. Injectable 

forms of the drug are also available but may cause 

irreparable muscle damage when administered over a 

longer period. Injectable forms are therefore not 

recommended. 

Currently, there has been success in the treatment of 

psittacosis using the newer quinolone antibiotics, such 

as enrofloxacin, also marketed under the name Baytril. 

This drug is more palatable and stable in the drinking 

water, and in its injectable form it is less likely to 

produce more muscle damage than are the 

tetracyclines. It appears also that cure rates may be 

obtained in 14-21 days. Baytril is widely available as an 

effective antibiotic for use in reptiles.


However, there is evidence to suggest that apparent 

'cures' using any of these drugs described above are in 

fact only clinical improvements and do not produce a 

long-term sustainable cure of the infection and full 

elimination of the organism. Additionally, execessive 

or prolonged doses of these drugs in Corallus caninus 

may, in many cases, prove to be fatal and should 

therefore be administered with great caution and care - 

Swan & Weidner [2002]. 

Cell destruction 

If EVS is in fact attributed to the presence of 

psittacosis, other complications may occur in Corallus 

caninus, as explained by Swan & Weidner [2002]. 

Since the infection, if left untreated for a longer period 

of time, has a highly destructive effect on the cells walls 

of the stomache in Corallus caninus, this may result, 

over time, in the permanent loss of HCl producing 

stomache cells. These HCl-producing cells are needed 

during the first stages of food processing in the 

stomache of the snake, i.e. for the conversion of prey 

into a ‘slush’-like mass which is normally processed 

further along the alimentary tract (small intestines) 

before feces are produced. 

This would account for the bone remnants found in 

excretions of feces by Corallus caninus as reported by 

Swan & Weidner [2002], where food masses have not 

been full processed during this initial ‘slushing stage’ 

in the stomache. The ‘slushed food mass’ is the result 

of the effects of the break-down effect of HClproducing 

cells in the stomache during the first few 

days following acceptance and presence of prey in the 

stomache. The destructive effect of psittacosis causes 

permanent, irreparable damage to these HClproducing 

cells which are essential for the initial 

breakdown of food masses. 

If this breakdown is not possible or substantially 

impaired, prey accepted and taken by Corallus caninus 

cannot physically continue down the alimentary tract 

and is therefore vomited up as a result. Therefore, until 

a positive diagnosis is obtained, specimens of Corallus 

caninus should preferably be fed smaller meals in 

order to allow for the possible destruction of cell tissue 

and loss of HCl-prducing cells in the lining of the 

stomache. If the destruction of cell tissue is severe, 

over time this will inevitabaly lead to the death of the 

snake (in which case euthanasia may be considered). 

However, if the destruction of HCl-producing cells is 

halted at a relatively early stage of the infection (by 

effective therapy), the remaining HCl-producing cells 

would enable the snake to survive the infection, 

provided that smaller prey is offered. 

The present author’s own findings seem to suggest that 

the breakdown of prey in the stomache of Corallus 

caninus takes longer than is generally assumed. In a 

collection of recently imported wild-caught Guyana 

specimens, only one of the 10 specimens exhibited 

symptoms similar to those seen in psittacosis by 

vomiting prey 48-72 hours after being fed. The prey 

vomited was found to be more or less fully intact and 

had not, after 72 hours, been substantially reduced by 

the HCl-producing cells. 

It was recorded that this vomiting occurred only after 

excessive spraying and misting in the confinement had 

occurred. It did not affect other specimens kept and 

cared for under exactly the same conditions and 

obtained from the same source in Guyana. On other 

occasions, this same individual would readily accept 

prey and produce healthy looking feces days after, 

without bone remnants present in the feces. 

Perhaps in this case, the vomiting may be attributed to 

stress-related factors or increased sensitivity of the 

individual to the abrupt and relatively high degree of 

humidity caused by spraying. The specimen was not 

clinically diagnosed as having psittacosis and no 

treatment with antibiotics had yet been initiated after 

the symptoms were observed. Analysis of the feces 

proved negative for worm and flagellate infections [the 

specimen had recently been treated preventively for 

worms and flagellates]. 

Treatment 

Whether we are dealing here with EVS or psittacosis, 

or even Cryptosporidiosis, it is most probably 

recommendable to carry out the following preventive 

treatment of specimens of wild-caught specimens of 

Corallus caninus when signs similar to those presented 

in psittacosis are observed. This preventive treatment 

would merely have the purpose of alleviating 

symptoms in an attempt to combat any possible 

infection by Chlamydophia psittaci. Whether it is 

effective or not depends on the underlying cause. 

Obviously, if symptoms diminish considerably or 

disappear after treatment with an antibiotic like 

Baytril, there would be reason to suggest that an 

infection was the probable cause, but not necessarily 

caused by psittacosis. If symptoms persist after 

treatment with an antibiotic, this would then suggest 

that other causes for the symptoms are present and 

should therefore be investigated (e.g. flagellate 

infections, worms, stress-related causes). In order to 

rule out infections by worms and/or flagellates, the 

recommended treatment would be as follows: 

A - treatment (following analysis of feces or 

preventively) of worm infestations by administering


Panacur (or similarly effective drug) to eliminate the 

possiblity of worm infections as the underlying cause; 

B – treatment of flagellate infections (either 

preventively or following positive results of feces 

analyses) by administering Flagyl (or similar drug) to 

eliminate a flagellate infection as the underlying cause. 

(This treatment should only be performed on the basis 

of positive laboratory results.) 

C – the oral administration of Baytril as a preventive 

measure, following the above regime in order to assist 

in elimination or alleviation of EVS in Corallus 

caninus. 

CONCLUSION 

In summary, therefore, it may be concluded that 

psittacosis is a disease that has long been recognised, 

but is yet still not fully understood. Many symptoms 

observed in EVS show great similarity with the signs 

most predominant in psittacosis for which there is, to 

date, no known long-term cure. Preventive treatment 

with an effective antibiotic from the tetracycline group 

of drugs seems to be the only remaining option in such 

cases, unless a positive diagnosis for psittacosis is 

made. Even then, the prognosis for specimens of 

Corallus caninus exhibiting these symptoms fro 

prolonged periods is very poor. 

Until further scientific studies are conducted under 

controlled laboratory conditions, any assumptions that 

EVS in Corallus caninus should be attributed to 

psittacosis may therefore only be considered as 

speculative. Cryptosporidiosis caused by 

Cryptosporidium serpentis must also be ruled out. 

However, due to the severity of the condition and the 

high mortality rate observed in indivdual specimens of 

Corallus caninus (and to some extent in e.g. Boa. c. 

constrictor and Eunectes notaeus) captured for the pet 

trade, further comprehensive scientific investigation is 

warranted by specialists in this field. 

It is important to differentiate psittacosis and 

Cryptosporidiosis from other causes of regurgitation 

and gastritis. Suboptimal temperatures, inappropriate 

prey size, stress, endoparasitic infections (caused by 

flagellates and worms) as well as foreign body 

obstructions in the alimentary tract are other potential 

causes of regurgitation. 

Additionally, strict hygiene, disinfection, longer 

periods of quarantine and isolation of all newly 

captured specimens of Corallus caninus are of 

paramount importance in controlling the disease, as is 

the segregation of avians from other wild-caught 

species in their countries of origin during and after 

storage and transport, whilst these animals await 

exportation and introduction into the collections of 

private breeders, herpetologists and zoos. 

___ 

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The Merck Veterinary Manual

The Source of Vomiting in the Emerald Tree Boa (Corallus caninus)

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