Evaluation of diagnostic coelioscopy including liver and kidney biopsy in freshwater turtles (Trachemys scripta)

[Diagnosis of kidney diseases in European tortoises (Testudo spp.)]

The diagnosis of kidney diseases in tortoises is only possible to a very limited extent on the basis of the general examination due to the development of unspecific disease symptoms. Extensive additional examinations are required to confirm the diagnosis. In addition to blood and urine tests, imaging techniques such as X-ray, computed tomography and MRI are suitable for visualizing the skeletal and organ systems, while additional samples can be taken during an endoscopic examination. There are clear species-specific differences with regard to the reference values of the laboratory parameters, which are in part significantly influenced by environmental influences, the seasons or even gender. It can also be seen that kidney diseases in tortoises kept in captivity are usually very advanced at the time of diagnosis, since these animals, like reptiles in general, show a pronounced lack of symptoms. Annual checks by a veterinarian specialized in reptiles can help to detect diseases at an early stage.

Circulating miRNome of Trachemys scripta after elective gonadectomy under general anesthesia

Post-surgical management is an important issue in veterinary medicine, requiring biomarkers with high sensitivity and specificity for timely and effective treatment. Emerging evidence suggests that miRNAs are promising stress- and pain-related markers. The aims were to profile the circulating miRNA signature in plasma of turtles (Trachemysscripta) and point out potential candidate biomarkers to assess the status of the animal. The plasma of female turtles underwent surgical gonadectomy were collected 24 h pre-surgery, and 2.5 h and 36 h post-surgery. The expression of miRNAs was profiled by Next Generation Sequencing and the dysregulated miRNAs were validated using RT-qPCR. The diagnostic value of miRNAs was calculated by ROC curves. The results showed that 14 miRNAs were differentially expressed over time. RT-qPCR validation highlighted that 2-miR-499-3p and miR-203-5p-out of 8 miRNAs tested were effectively modulated. The Area Under the Curve (AUC) of miR-203-5p was fair (AUC 0.7934) in discriminating pre- and 36 h post-surgery samples and poor for other time points; the AUC of miR-499-3p was excellent (AUC 0.944) in discriminating pre-surgery and 2.5 h post-surgery samples, and fair in discriminating pre-surgery and 36 h post-surgery (AUC 0.7292) and 2.5 h and 36 h post-surgery (AUC 0.7569) samples. In conclusion, we demonstrated for the first time that miRNAs profile changes in plasma of turtles underwent surgical oophorectomy and identified miR-203-5p and miR-499-3p as potential candidate biomarkers to assess animals' status. Further studies are necessary to confirm their diagnostic value and to investigate functional and mechanistic networks to improve our understanding of the biological processes.

TOMOGRAPHIC ATTENUATION OF THE HEPATIC PARENCHYMA OF ADULT FREE-RANGING AND CAPTIVE BOAS (BOA CONSTRICTOR)

Improperly managed care conditions for reptiles can lead to clinical problems, including those of nutritional origin. A diagnostic tool to aid in the assessment of hepatic lipidosis is warranted. Evaluation of attenuation using quantitative computed tomography has a variety of indications in animals and permits the standardization of hepatic computed tomography (CT) reference values, aiding in the diagnosis of lipidosis. The objective of this paper was to estimate hepatic quantitative CT reference values for boas because of the lack of data in the literature for this species. CT scans were performed in 13 boas (Boa constrictor constrictor): 5 under managed care and 8 that were free ranging. Results show that the mean hepatic attenuation in the captive boa group was well below the mean for the free-ranging animals (P < 0.05) with respective values of 48.78 ± 6.57 and 61.76 ± 7.11 HU. These results suggest an influence of managed care on liver attenuation. These results were observed despite the lack of clinical or laboratory changes. This imaging technique is useful to detect early hepatic changes; however, clinical relevance is unknown at this point. Further studies and standardization of species-specific values for hepatic quantitative CT would contribute to better understanding of the physiologic, physiopathologic, environmental, and nutritional processes.

Comparison of Lateral and Dorsal Recumbency during Endoscope-Assisted Oophorectomy in Mature Pond Sliders (Trachemys scripta)

Simple Summary

Ovariectomy via the prefemoral fossa, with or without endoscopic assistance, is a well-described technique for elective and therapeutic sterilization in chelonians. The choice between lateral and dorsal recumbency is generally left to the surgeon’s preference, with no data supporting an objective superiority of one over the other. In pond sliders, common pets but also an invasive alien species in Europe, we compared two different recumbencies (right lateral with a left fossa approach, and dorsal with a right fossa approach) regarding ease of access to the coelomic cavity, ease of identification of the ovary opposite to the surgical breach, first and second ovary removal times, and total surgical time. No significant difference was found between the two groups for any evaluated parameter. Endoscope-assisted prefemoral ovariectomy in mature pond sliders can be indifferently performed in lateral or dorsal recumbency, depending on the preference of the surgeon, on the animal’s pathophysiologic status, or on the necessity to perform concurrent procedures.

Abstract

Ovariectomy via the prefemoral fossa is a well-described technique for sterilization in chelonians. The choice between lateral and dorsal recumbency is generally left to the surgeon’s preference, with no data supporting an objective superiority of one over the other. Twenty-four sexually mature female pond sliders (Trachemys scripta) were enrolled for elective prefemoral endoscope-assisted oophorectomy, and were randomly divided in two groups: 12 animals were placed in right lateral recumbency with a left fossa approach (Group A), and 12 in dorsal recumbency with a right fossa approach (Group B). Scoring systems were applied to assess the ease of access to the coelomic cavity, and the ease of identification of the ovary opposite to the surgical incision. A negative correlation was found between the body weight of the animals and the ease of access to the coelom (p = 0.013), making the access easier in smaller animals. No significant difference was found between the two groups in terms of ease of access to the coelomic cavity, first ovary removal time, ease of identification of the second ovary, second ovary removal time, or total surgery time.

Evaluation of a ventral and a left lateral approach to coelioscopy in bearded dragons (Pogona vitticeps)

OBJECTIVE

To compare a ventral and a left lateral endoscopic approach to coelioscopy in bearded dragons (Pogona vitticeps).

ANIMALS

18 adult bearded dragons.

PROCEDURES

In a randomized crossover design involving 2 surgical approaches, anesthetized bearded dragons first underwent coelioscopy with a ventral approach (left lateral of midline next to the umbilicus; animal positioned in dorsal recumbency) or left lateral approach (intercostal; animal positioned in right lateral recumbency) and then with the alternate approach. A 2.7-mm × 18-cm, 30° oblique telescope with a 4.8-mm operating sheath and CO₂ insufflation at 2 to 5 mm Hg were used. Ease of entry into the coelom and ease of visual examination of visceral structures were scored.

RESULTS

Both approaches were straightforward, with the left lateral approach requiring significantly more time than the ventral approach. Scores for ease of visual examination for the heart, lungs, liver, stomach, intestines, pancreas, gallbladder, left kidney, gonads, and fat body were good to excellent. Visual examination of the spleen and adrenal glands was difficult in most animals via either approach. The left kidney, testis, and vas deferens were easier to see with the left lateral approach, whereas the pancreas in females and gallbladder in both sexes were easier to see with the ventral approach. All bearded dragons recovered without complications from the procedures, except for one with nephritis, renal gout, and hepatic necrosis.

CONCLUSIONS AND CLINICAL RELEVANCE

Both coelioscopy approaches could be safely and effectively used in bearded dragons. Choice of approach should be based on the coelomic structures requiring evaluation.

Clinical Manifestation and Molecular Characterization of a Novel Member of the Nannizziopsiaceae in a Pulmonary Granuloma From a Galapagos Tortoise (Chelonoidis nigra)

Nannizziopsiaceae is a family of fungal organisms within the order Onygenales containing two genera of important reptile pathogens, Nannizziopsis and Paranannizziopsis. A captive Galapagos tortoise (Chelonoidis nigra) from Boca Raton, Florida, United States, was presented for a clinical history of chronic progressive lethargy and inappetence. At initial presentation, the tortoise had a moderate non-regenerative anemia, leukocytosis, whip-like heterophil projections, erythrocyte fragmentation, and fibrin strands, with the latter two raising concern for disseminated intravascular coagulation. A single large encapsulated pulmonary granuloma was identified through imaging, including plain film radiography and bronchoscopy. Direct intralesional samples were obtained from transcarapacial celioscopy for fungal culture, cytology, histopathology, and polymerase chain reaction. Amplification and sequencing of the ITS2 region of the rRNA genes with Bayesian and maximum likelihood analyses placed the fungus in the family Nannizziopsiaceae within the order Onygenales, representing a novel fungal species.

Diagnostic Imaging of the Reptile Urinary System

Reptiles can develop various diseases of the urinary tract, including, but not exclusively, urolithiasis, gout, acute and chronic kidney injury, and secondary renal hyperparathyroidism. Diagnostic imaging is instrumental in differentiating and diagnosing these ailments. This article describes the current diagnostic imaging approaches used in reptile medicine for evaluation of urinary tract disease. The use of radiographs, ultrasonography, computed tomography, MRI, and endoscopy is discussed and compared for the evaluation of urinary tract disease in reptiles.

Evaluation of diagnostic coelioscopy in koi (Cyprinus carpio)

OBJECTIVE To describe a technique for endoscopic evaluation of the coelomic viscera of koi (Cyprinus carpio) and to evaluate the ability to visually examine coelomic structures by use of an approach cranial or caudal to the pelvic girdle. ANIMALS 16 subadult koi. PROCEDURES Koi were anesthetized with buffered tricaine methanesulfonate. Coelioscopic examination was performed via a ventral midline incisional approach cranial or caudal to the pelvic girdle. A 2.7-mm × 18-cm 30° oblique endoscope within a 4.8-mm operating sheath and infusion of saline (0.9% NaCl) solution was used. Ease of entry into the coelomic cavity and visual examination of structures were scored for each fish. Fish were euthanized 2 or 8 weeks after the procedure, and necropsy was performed. RESULTS The coelioscopic procedure was tolerated well, and all koi recovered uneventfully. For all fish, ease of entry and visual examination scores of the liver, intestines, gonads, heart, and anterior kidney were satisfactory to excellent. Visual examination of the posterior kidney and swim bladder was satisfactory to difficult, whereas the spleen and gallbladder were not visually identified. No significant differences were noted in entry or visual examination scores between the cranial and caudal approaches or between sexes. Minor complications included mild hemorrhage, rupture of the gonadal capsule, formation of adhesions between the viscera and incision site, and delayed healing of the incision. CONCLUSIONS AND CLINICAL RELEVANCE Diagnostic coelioscopy of koi appeared to be safe and effective. This procedure could have potential for use in examination of coelomic structures and disease diagnosis.

Endoscopic assisted orchiectomy in Herman’s tortoises (Testudo hermanni sp.)

Objective: Male tortoises in captivity are often aggressive against other males or females, in particular during mating season related to hormonal influences (testosterone). Castration in males is the treatment of choice in many vertebrate species. A novel technique of minimal invasive castration is presented for Herman’s tortoises (Testudo hermanni).

Material and methods: The procedure was performed in ten mature males. An endoscope (2.7 mm/30° angled) was inserted into a prefemoral incision on each side. The testicle was resected after ligation of the gubernaculum testis and the spermatic cord using hemoclips.

Results: Each testicle could be removed in approximately 20 minutes. Complications like hemorrhage or damage of adjacent tissue did not occur and all animals recovered uneventfully.

Conclusions and clinical relevance: Using the bilateral prefemoral entrance offers an alternative option for orchiectomy in Herman’s tortoises without dissection of the shell. Thus complications like hemorrhage or impaired wound healing followed by sequestration of the bone flap are prevented. Because of the anatomical settings and the risk of tissue damage and time consumption, a unilateral approach is not recommended. Fasting the animals is necessary due to the voluminous gastrointestinal tract of this herbivorous tortoise and emptying the urinary bladder provides more space for manipulations in the coelomic cavity and prevents clipping and cutting of adjacent organs. The magnification via the endoscope is beneficial for orientation in the coelomic cavity, which is formed by the extremely convex carapace. Without this equipment it is challenging to visualize the dorsocaudally located gonads through the relatively small incision and the inserted instruments might block the view at the surgical field. Administration of hemoclips achieved a good hemostasis and the testicles could be resected without major blood loss. The described technique is a gentle method for resection of the testicles in this species and can be adapted to other European tortoise species of equal size.

Tissue uptake, distribution and excretion of brevetoxin-3 after oral and intratracheal exposure in the freshwater turtle Trachemys scripta and the diamondback terrapin Malaclemys terrapin

Harmful algal blooms (HABs) occur nearly annually off the west coast of Florida and can impact both humans and wildlife, resulting in morbidity and increased mortality of marine animals including sea turtles. The key organism in Florida red tides is the dinoflagellate Karenia brevis that produces a suite of potent neurotoxins referred to as the brevetoxins (PbTx). Despite recent mortality events and rehabilitation efforts, still little is known about how the toxin directly impacts sea turtles, as they are not amenable to experimentation and what is known about toxin levels and distribution comes primarily from post-mortem data. In this study, we utilized the freshwater turtle Trachemys scripta and the diamondback terrapin, Malaclemys terrapin as model organisms to determine the distribution, clearance, and routes of excretion of the most common form of the toxin, brevetoxin-3, in turtles. Turtles were administered toxin via esophageal tube to mimic ingestion (33.48μg/kg PbTx-3, 3×/week for two weeks for a total of 7 doses) or by intratracheal instillation (10.53μg/kg, 3×/week for four weeks for a total of 12 doses) to mimic inhalation. Both oral and intratracheal administration of the toxin produced a suite of behavioral responses symptomatic of brevetoxicosis. The toxin distributed to all organ systems within 1h of administration but was rapidly cleared out over 24-48h, corresponding to a decline in clinical symptoms. Excretion appears to be primarily through conjugation to bile salts. Histopathological study revealed that the frequency of lesions varied within experimental groups with some turtles having no significant lesions at all, while similar lesions were found in a low number of control turtles suggesting another common factor(s) could be responsible. The overall goal of this research is better understand the impacts of brevetoxin on turtles in order to develop better treatment protocols for sea turtles exposed to HABs.

Reptile Soft Tissue Surgery

The surgical approach to reptiles can be challenging. Reptiles have unique physiologic, anatomic, and pathologic differences. This may result in frustrating surgical experiences. However, recent investigations provided novel, less invasive, surgical techniques. The purpose of this review was to describe the technical aspects behind soft tissue surgical techniques that have been used in reptiles, so as to provide a general guideline for veterinarians working with reptiles.

Single surgeon coelioscopic orchiectomy of desert tortoises (Gopherus agassizii) for population management

Orchiectomy in chelonians is a challenging procedure, especially in large species with deep and elongated testes and extensive mesorchial attachments. Single surgeon coelioscopic orchiectomy was performed in seven adult desert tortoises (Gopherus agassizii), maintained at the Desert Tortoise Conservation Center (DTCC) in Las Vegas, for population management. Surgery was successfully conducted through a bilateral prefemoral approach via sequential vascular clip ligation and radiosurgery (monopolar/bipolar). Bipolar endoscopic forceps were considered indispensable due to the extensive mesorchial attachments and their close association with the kidney. A mechanical arm was effectively used to permit orchiectomy to be completed by a single surgeon. Six of seven animals recovered from anaesthesia. Necropsy demonstrated that the death of the other was unrelated to surgical complications. One animal experienced surgically significant haemorrhage, but still made a clinical recovery. The six tortoises were returned to the DTCC and, six months postoperatively, remain healthy. This small study suggests this minimally invasive technique is an effective method for bilateral orchiectomy in desert tortoises and might be preferable in large chelonians with elongated testes.