Diseases of tortoises: a review of seventy cases

Conjunctival bacterial flora and antimicrobial susceptibility of captive and free-living sea turtles in Brazil

PURPOSE

To describe the aerobic conjunctival bacterial flora of 3 especies of free-living and under human care sea turtles and determine its antimicrobial susceptibility in vitro.

METHOD

Thirty-six sea turtles (72 eyes), juveniles and adults, 7 free-living Chelonia mydas and 8 Chelonia mydas, 4 Caretta caretta, 11 Eretmochelys imbricata, and 6 Lepidochelys olivacea under human care, were evaluated. Conjunctival cultures were collected for identification of aerobic bacteria and antimicrobial susceptibility testing for ciprofloxacin, chloramphenicol, gentamicin, neomycin, oxacillin, polymyxin B, tetracycline, and tobramycin using antibiotic disks. Bacterial strains showing no sensitivity to 4 or more antimicrobials were considered multiresistant to this panel.

RESULTS

Bacterial growth was observed in 12/14 (85.71%) samples in the free-living sea turtles, and there was growth in 100% (58/58) of the samples from captive animals. There were 94 strains isolated and 15 species identified. There was a predominance of Gram-positive bacteria in free-living Chelonia mydas, most of which were Bacillus and Staphylococcus. The most commonly isolated Gram-negative species were enterobacteria for free-living and under human care animals. The strains were predominantly sensitive to ciprofloxacin and tobramycin, and less sensitive to oxacillin or polymyxin B. Ten multiresistant strains were isolated. Yeast were identified in 13.89% (10/72) of the samples.

CONCLUSIONS

These results, showing differences in the conjunctival bacterial flora of free-living and captive animals, may be helpful for diagnosis and treatment of ocular disorders in sea turtles.

Conjunctival flora of clinically normal and diseased turtles and tortoises

BACKGROUND

In captive breed turtles and tortoises conjunctival disease is common. Our aim was to investigate the bacterial and fungal flora present in the eyes of healthy and pathological chelonians and to compare findings in turtles with those in tortoises.

RESULTS

Samples were taken from the conjunctival sacs of 34, diseased and healthy, chelonians (18 tortoises and 16 turtles) and submitted to bacterial and fungal investigation. All samples showed bacterial growth. Thirteen animals (38%), harboured a single bacterial species as sole isolate and twenty-one animals (62%) harboured more than one species. Detection of multiple bacterial infection was clearly greater in tortoises compared to turtles. Most frequently isolated bacterial species were Bacillus spp. (13 isolates), Staphylococcus xylosus (10 isolates), Sphingomonas paucimobilis (6 isolates), Staphylococcus sciuri and Aeromonas hydrophila/caviae (each 5 isolates), Ochrobactrum anthropi (3 isolates), Citrobacter freundii, Enterobacter cloacae and Pseudomonas luteola (each 2 isolates). Only one isolate of Kocuria varians/rosea, Staphylococcus aureus, Staphylococcus auricularis, Staphylococcus haemolyticus, Staphylococcus lentus, Morganella morganii, Pasteurella multocida, Pasteurella pneumotropica/haemolytica, Proteus spp., Pseudomonas putida, Salmonella enterica ssp. arizonae, Stenotrophomonas maltophilia and Vibrio parahaemolyticus was evidenced. The presence in 8 animals of Mycoplasma spp. and in 1 animal with severe conjunctivitis of Chlamydia spp. was detected by PCR. Candida spp. was also isolated from two healthy animals.

CONCLUSIONS

A clear predominance of Gram positive isolates in tortoises and Gram negative isolates in turtles was found. However, we cannot ascribe the observed difference to the diversity of animal species, as other factors, including especially different characteristics of the living environments, may play a role. Almost all bacterial species isolated may have clinical significance, mostly as opportunistic pathogens, both for humans and animals. That chelonians are often carrier of bacteria with zoonotic potential is a well-known fact, in particular with regard to Salmonella spp. Therefore, it is not surprising the detection of a strain of Salmonella enterica ssp. arizonae in the eye of one of the animals tested. Worthy of note is the finding of Chlamydia spp. in a severe case of conjunctivitis, though we cannot epidemiologically assess a cause-effect relationship between presence of chlamydia and disease.

Occurrence of Camallanus trispinosus in a captive Indian star tortoise (Geochelone elegans)

Camallanoids are spirurid round worms known to occur in stomach and intestine of lower vertebrate animals such as fishes and reptiles. This paper records the occurrence of Camallanus trispinosus in a captive Indian star tortoise of Guindy snake park, Chennai, India for the first time during necropsy and identified on the basis of morphology of male and female worms, including eggs.

Differences in helminth infections between captive and wild spur-thighed tortoises Testudo graeca in southern Spain: a potential risk of reintroductions of this species

Although the spur-thighed tortoise, Testudo graeca, is one of the most widely distributed species of tortoises, its natural populations are threatened through its whole range. Particularly at south-eastern Spain, the species is mainly threatened by habitat destruction and over-collection, given that this chelonian has been traditionally considered an appreciate pet. As south-eastern Spanish wildlife recovery centers shelter hundreds of captive animals mainly coming from illegal trade or captive-bred, there is a strong debate about what to do with these animals: maintaining them in captivity all along their lives or reintroducing them to wildlife. It is well known that the reintroduction of captive animals supposes a risk for the wild population due to the uncertainty of their genetic origin and to the possible spread of infectious diseases. However, despite the increasing evidence that infectious agents are a potential health hazard for wildlife, little is known about the risk that introduced parasites could suppose for the wild populations of spur-thighed tortoise. The present study investigates for the first time the presence of helminth eggs and worms in faeces from 107 wild and captive individuals collected from mid-March to mid-June 2010, and relates the findings to different environmental and host variables. Sixteen oxyurid species and the ascarid Angusticaecum holopterum were identified. This last nematode and the oxyurid species Tachygonetria palearticus and T. seurati had not been reported in Spanish wild T. graeca previously. The prevalence of oxyurid eggs and worms were 94% and 70%, respectively; while, ascarid eggs and worms were found in 26% and 5% of tortoises, respectively. Ascarid infections affected mostly captive animals and were associated to caparace deformities and symptoms of upper respiratory tract disease (p<0.05). Oxyurid infections were not associated to negative health traits and prevalence increased with age. In free-living tortoises, the distribution of pharingodonid genera also varied according to habitat; moreover, T. longicollis, T. pusilla, T. conica, T. robusta and Mehdiella stylosa where significantly more frequent in wild compared to captive tortoises (p<0.05). Study results highlight important differences in the nematode fauna of captive and free-living tortoises and questions one more time if the reintroductions of captive animals suppose a risk for the wild population since the former ones can harbor and distribute among free populations pathogens like ascarid nematodes.

Epidemiology and biology of nematodofauna affecting Testudo hermanni, Testudo graeca and Testudo marginata in Italy

Tortoises of the genus Testudo living in Italy are Testudo hermanni, Testudo graeca and Testudo marginata. Although a great deal of information has been acquired on the internal medicine and surgery on these animals, little is known of their parasitological fauna. A survey on the presence of gastro-intestinal parasitic nematodes in tortoises bred in Italy was carried out to acquire extensive epidemiological data. Stool samples of 62 tortoises (37 T. hermanni hermanni, 13 T. graeca, 6 T. hermanni boettgeri and 6 T. marginata) were macroscopically examined and subjected to qualitative (flotation and Baermann techniques) and quantitative (McMaster technique) microscopic examinations. Adult nematodes were identified using morphological keys. Eggs of oxyurids (species indistinguishable) and adults of Alaeuris numidica, Mehdiella microstoma, Mehdiella uncinata, Tachygonetria longicollis, Tachygonetria conica and Tachygonetria palearcticus (Oxyurida, Pharyngodonidae); larvae and adults of Atractis dactyluris (Ascaridida, Atractidae); and eggs and adults of Angusticaecum holopterum (Ascaridida, Ascarididae) were identified in all animals >1 year, whereas all tortoises <1 year of age were parasite-free. Moreover, this study reports for the first time A. numidica and M. microstoma in T. marginata. This work shows that nematodes affecting tortoises are diffused in Italy and highlights the need to investigate their epidemiology more in depth.

Dacryops in a red-eared slider (Chrysemys scripta elegans): case report

Clinical and histologic findings of an orbital lacrimal cyst (dacryops) in a 23-year-old-female red-eared slider (Chrysemys scripta elegans) are described. Main ophthalmologic findings included unilateral exophthalmus, engorged episcleral vessels, periocular swelling superior to the globe, incomplete lid closure, and reduced ocular motility. Based on sonographic and cytologic examination of the tissue, the preliminary diagnosis of an orbital cyst was established. After surgical resection of the cystic structure, the eye remained visual but enophthalmic. Histopathologic diagnosis of the resected tissue was interstitial dacryoadenitis.

Polymerase chain reaction (PCR) for the detection of herpesvirus in tortoises

A polymerase chain reaction (PCR)-based method using a herpesvirus consensus primer was assessed for the identification of herpesviral infections in tortoises. A single band of about 230 bp was detected in PCR products from two out of twenty swabs taken from the oral cavity, three out of three paraffin-embedded tissue sections from the liver (two cases) and oral mucosa (one case), and one out of two fresh tissue samples from the oral mucosa. Nucleotide sequencing of these PCR products indicated that the herpesvirus present in these tortoises might belong to the alphaherpesvirinae. PCR using swabs and biopsy tissues was a sensitive and highly specific method for the diagnosis of herpesviral infections in tortoises.

Intestinal Cryptosporidium sp. infection in the Egyptian tortoise, Testudo kleinmanni

An adult Egyptian tortoise (Testudo kleinmanni) presented with clinical signs of enteritis and died 5 weeks after initiation of antibiotic therapy. Histological examination of the small intestine revealed heavy infection with Cryptosporidium sp.; over 80% of epithelial cells harboured the pathogen. No Cryptosporidium developmental stages were present in the stomach or the lungs. The intestinal lamina propria and mucosa were infiltrated by heterophils, lymphocytes and macrophages. The present study constitutes the first report of Cryptosporidium sp. infection in T. kleinmanni, and the first histological documentation of intestinal cryptosporidiosis in Chelonia.

Cutaneous hyalohyphomycosis caused by Fusarium solani in a loggerhead sea turtle (Caretta caretta L.)

Fusarium solani was reported as the agent of a cutaneous infection in an injured sea turtle collected in the Mediterranean Sea. The turtle was treated with both a topical 10% solution of iodine in alcohol and ketoconazole. The source of the causal agent was traced to the sand in the tank in which the turtle was maintained. The strain was only sensitive in vitro to amphotericin B and was resistant to 5-fluorocytosine, fluconazole, itraconazole, and ketoconazole.