coelioscopic orchiectomy can be effectively and safely accomplished in chelonians

May 18, 2013 | Veterinary Record

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Coelioscopic orchiectomy can be effectively and safely accomplished in cheloniansC. J. Innis, R. Feinsod, J. Hanlon, S. Stahl, J. Oguni, S. Boone, R. Schnellbacher, J. Cavin, S. J. Divers

Coelioscopic orchiectomy was performed in 27 male turtles (25 juvenile to adult red-eared sliders (Trachemys scripta elegans), one adult eastern painted turtle (Chrysems picta picta), and one juvenile male yellow-spotted Amazon River turtle (Podocnemis unifilis)). Orchiectomy was conducted under coelioscopic visualisation using ligation and transection of the mesorchium, or transection of the mesorchium with monopolar radiosurgical scissors. In 22 cases, bilateral orchiectomy was performed through a single incision; five turtles required bilateral incisions. All turtles recovered from anaesthesia. Nine turtles died within one year of surgery from conditions believed to be unrelated to surgery. One turtle was lost to follow-up. Seventeen turtles remain clinically healthy one to three years postoperatively. Coelioscopic orchiectomy provides a minimally invasive method for sterilisation of male chelonians and provides excellent visualisation during surgery. This technique is a useful model for the development of additional minimally invasive surgical techniques for chelonians.

IntroductionOrchiectomy is a routine procedure in many mammalian species. It is commonly performed clinically for contraception and manage-ment of various medical and behavioural problems. Experimentally, orchiectomy serves an important role in basic scientific research on the endocrine and reproductive systems in a variety of species, including turtles (Licht and others 1985). Sterilisation of male chelonians may be desirable to prevent inbreeding of related captive individuals, to reduce potentially traumatic courtship behaviour, to prevent breeding of free-ranging genetically hybridised specimens, or for management of testicular neoplasia (Frye and others 1988, Rivera and others 2011).

The testes of turtles are located in the dorsocaudal coelomic cav-ity, below the carapace, and are thus challenging to access surgically (Rivera and others 2011). Unlike the relatively long, flaccid mesovar-ium of mature turtle ovaries, the mesorchium of turtles is short and tight, such that the testes cannot be exteriorised from the coelom. Contraception or sterilisation of male turtles has been conducted via phallectomy, orchiectomy via shell osteotomy, or prefemoral orchi-ectomy (Lawson and Garstka 1985, Licht and others 1985, Rivera and others 2011, Kinney and others 2011). While phallectomy may prohibit normal chelonian copulation, the presence of still-functional testes maintains potential fertility. Although shell osteotomy has been

successfully used for a variety of chelonian surgical procedures, it is associated with prolonged healing times, and may be complicated by sequestration of the bone flap (Mader and others 2006, CJ Innis and SJ Divers, personal observations). As an alternative to shell oste-otomy, coeliotomy via the prefemoral region has been recommended (Brannian 1984, Gould and others 1992) and has been utilised with-out coelioscopy for gonadectomy of turtles (Minter and others 2008, Kinney and others 2011). Minimally invasive coelioscopic and coe-lioscopic-assisted management of the female reproductive tract of tur-tles, including oophorectomy has been described, and offers improved visualisation compared with standard surgical methods (Innis and oth-ers 2007, Knafo and others 2011). This may be especially important for very large chelonians where the gonads may be very deep relative to the skin incision, or in cases where extensive dissection is required (Knafo and others 2011). In addition, endoscopic techniques often allow for smaller surgical incisions than those required for traditional surgery. The purpose of the present report is to describe results of a prospective evaluation of coelioscopic orchiectomy in chelonians, and to describe use of this technique in three clinical patients.

Materials and methodsProspective study patientsSurgical procedures involving experimental turtles in this study were approved by the Animal Care and Use Committee (A2010 11-549-Y2-A1) of the University of Georgia (UGA), College of Veterinary Medicine, Athens, Georgia, USA, and were conducted at UGA. Twenty-five juvenile to adult red-eared slider turtles (Trachemys scripta elegans) were acquired to assess the feasibility and safety of coelioscop-ic orchiectomy, and to compare two methods of testicular excision. Experimental turtles were acclimated for at least one month prior to surgery and were randomly assigned to one of two surgical methods.

Clinical patientsThree turtles (one adult red-eared slider, one adult eastern painted turtle (Chrysemys picta picta), and one juvenile male yellow-spotted Amazon River turtle (Podocnemis unifilis)) were privately owned clini-cal cases that were neutered for contraceptive or behavioural pur-poses. The Amazon River turtle was five years old, and was hatched

Veterinary Record (2013) doi: 10.1136/vr.101475

C. J. Innis, VMD, DABVP (Reptile and Amphibian)J. Cavin, DVMAnimal Health Department, New England Aquarium, Boston, MA 02110, USAR. Feinsod, DVMJ. Hanlon, CVTAni-Care Animal Hospital, Dallastown, PA 17313-9541, USAS. Stahl, DVM, DABVP (Avian)Stahl Exotic Animal Veterinary Services, Fairfax, VA 22030, USA

J. Oguni, DVMS. Boone, DVM, MSR. Schnellbacher, DVMS. J. Divers, BVetMed, DZooMed, DipECZM (herpetology) DACZM, FRCVSDepartment of Small Animal Medicine (Zoological Medicine), College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA

E-mail for correspondence: [email protected]

Accepted March 7, 2013

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Veterinary Record | May 18, 2013

in captivity. The exact age and origin of the remaining turtles were unknown, as they had been obtained as mature animals. Procedures were conducted at New England Aquarium, Boston, Massachusetts, USA (Chrysemys and Podocnemis), or VCA Westboro Animal Hospital, Westboro, Massachusetts, USA (Trachemys).

ProceduresFood was withheld for 24 hours prior to surgery. Routine preopera-tive examination was conducted, and an attempt was made to empty the urinary bladder of each turtle via digital stimulation of the cloaca and prefemoral palpation. Turtles were provided pre-emptive anal-gesia, with morphine (Morphine sulphate injection, Elkins-Sinn) administered at 1 mg/kg intramuscularly, and meloxicam (Metacam, Boehringer Ingelheim) administered at 0.2–0.4 mg/kg intramus-cularly. Perioperative antimicrobial coverage was provided by the administration of either ceftazidime (Fortaz, Glaxo SmithKline) at 20–40 mg/kg intramuscularly, or oxytetracycline (Liquamycin LA200, Pfizer) at 50 mg/kg intramuscularly. Anaesthesia was induced with either alfaxolone (Alfaxan, Jurox) administered at 20 mg/kg intramuscularly, or an intravenous combination of 5–7 mg/kg keta-mine (Ketaset, Fort Dodge), and 25–70 µg/kg dexmedetomidine (Dexdomitor, Pfizer) injected into the dorsal coccygeal vein. An appro-priately sized uncuffed endotracheal tube was inserted and anaesthesia was maintained with isoflurane or sevoflurane in oxygen delivered through a non-rebreathing circuit. Positive-pressure ventilation (one to four breaths/min at peak inspiratory pressure of 4 to 10 mm Hg) was provided manually or by use of a ventilator (Small animal ventilator VT-5000, BAS Vetronics, Bioanalytical Systems; or Multiflow 2002 Anaesthesia Ventilator, Hallowell EMC, customised for respiratory rates <6 bpm). Heart rate was monitored with a Doppler ultrasonic flow detector (model 811-B; Parks Medical Electronics) placed over the carotid artery; end-tidal partial pressure of CO2 was monitored with a capnograph (TidalWave Sp Model 710; Philips Respironics; or NPB-70, Nellcor); and body temperature was monitored via a digital thermometer inserted into the cloaca.

Once a surgical plane of anaesthesia was achieved, each turtle was placed in right lateral recumbency on a heated surgical table (28°C to 30°C), with its hind end elevated at approximately a 30° to 45° angle. The left hind leg was restrained in extension to expose the prefemoral region. The prefemoral region and surrounding shell was aseptically prepared with chlorhexidine surgical srcub and isopropyl alcohol, surgically draped, and infused with 2 mg/kg lidocaine (lido-caine injectable 2 per cent, AgriLabs), which was buffered 5:1 by vol-ume with sodium bicarbonate (sodium bicarbonate injectable 7.5 per cent, American Regent) for procedures performed at UGA. Lidocaine was infused into the skin and subcutaneous tissue, and infusion was continued as the needle was advanced toward the coelom, with the goal of delivering lidocaine into the coelomic muscle wall.

Surgeries were performed by pairs of veterinarians formed from a total of eight veterinarians (seven at UGA, two in MA, one participat-ed at both locations). A 2 to 4-cm-long craniocaudal skin incision was made with a #15 scalpel in the centre of the prefemoral fossa, and sub-cutaneous connective tissue and fat were bluntly dissected to expose

the tendinous aponeurosis of the transverse and oblique abdominal muscles. The aponeurosis was incised to expose the coelomic vis-cera. Coelomic insufflation was not required. Coelioscopy was per-formed with a 30°, 18 cm×2.7 mm telescope (64018BSA, Karl Storz Veterinary Endoscopy (KSVEA)) inserted through either a 3.5 mm or 4.8 mm sheath (64018US or 67065CV, KSVEA) and connected to a xenon light source (201315-20, KSVEA). Endoscopic equipment was disinfected with 2 per cent glutaraldehyde (14 day Cidex, or 28 day Cidex; Advanced Sterilisation Products) for 15–30 minutes and rinsed using sterile water before use. The liver, gall bladder, heart, stomach, intestines, urinary bladder, lung, testes, kidneys and adrenal glands were identified and examined (Fig 1). If the urinary bladder was large and prevented excellent visualisation of the testes, intraoperative cys-tocentesis was performed under endoscopic guidance using a syringe and 22 gauge needle directed through the surgical incision.

After examination of the coelomic cavity, a 5 mm×36 cm Kelly grasping forceps (33310ML with sheath 33400, KSVEA) or 5 mm×36 cm Babcock forceps (33310A forceps with sheath 33400, KSVEA), with ratchet handle (33123, KSVEA) or without ratchet handle (33121, KSVEA); or 3 mm×20 cm Babcock forceps with ratchet handle (30341AS, KSVEA) was inserted into the coelomic cavity alongside the endoscope, and was used to grasp the ipsi-lateral (left) testis and elevate it to expose the mesorchium (Fig 2). A second surgeon then utilised one of two methods for excision of the testis. In approximately 50 per cent of cases, the mesorchium was ligated with stainless steel vascular clips (Hemoclips medium size, Weck) (Fig 3), and transected distal to the clips with 5 mm×36 cm curved Metzenbaum endoscopic scissors (34325MS, KSVEA) (Fig 3). For the other cases, the mesorchium was transected without liga-tion using 3 mm×20 cm curved Metzenbaum scissors (34325MS; KSVEA) attached to a radiosurgery unit (Surgitron 4.0 MHz; Ellman International) used as a monopolar device (Fig 4). Coelioscopic exami-nation of the surgical site was performed to verify hemostasis and to verify complete excision of testicular tissue (Figs 3d and 4b). If the

FIG 1: Left coelioscopic view of the left testis (T), left epididymis (E), left kidney (K), left renal vein (V), descending colon (C), and left lung (L) of a male red-eared slider turtle (Trachemys scripta elegans).

FIG 2: Left coelioscopic view of the retracted left testis (T), mesorchium (M), and epididymis (E) of a male red-eared slider turtle (Trachemys scripta elegans). (a) The left testis is grasped with endoforceps, being careful to avoid the lung (L), epididymis and renal vein (V). (b) The left testis is elevated from the epididymis to expose the mesorchium containing numerous blood vessels.




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contralateral (right) testis could be identified and clearly isolated from adjacent tissues, orchiectomy was conducted via a unilateral incision. If not, the first incision was closed, the patient was repositioned into left lateral recumbency, and the right testis was approached via a right prefemoral incision.

The coelomic aponeurosis was closed with 3-0 polydioxanone suture (PDS II; Ethicon), in a simple continuous pattern. Skin was closed with 3-0 nylon (Ethilon, Ethicon) or polydioxanone in a hori-zontal mattress pattern or with skin staples (3M Health Care).

A single dose of postoperative subcutaneous fluid therapy was provided using 20 ml/kg lactated Ringer’s (Hospira). Turtles that had been treated with dexmedetomidine were given the reversal agent, ati-pamezole (Antisedan, Pfizer) intramuscularly at 10 times the dexme-detomidine dose. At the discretion of attending clinicians, some turtles were treated postoperatively with naloxone (Hospira) at 0.2 mg/kg intramuscularly for opioid reversal.

The three clinical cases were returned to their private owner or zoological institution where they remained available for long-term follow-up. Full access to water was provided within 24 hours after surgery. Experimental turtles were released into a fenced outdoor pond

at the private facility of one of the authors (RF) 2–3 days postopera-tively for long-term monitoring. Skin sutures or staples were removed 4–8 weeks postoperatively. Coelioscopy was repeated 14 months postoperatively for 11 of the experimental turtles to reassess the surgi-cal sites using established techniques (Divers 2010).

ResultsOne turtle was removed from the prospective study due to iatrogenic perforation of the urinary bladder during surgery, prior to orchiec-tomy. Coelioscopic orchiectomy was successfully performed on 27 male turtles without major anaesthetic or surgical complications (25 juvenile to adult red-eared sliders, one adult eastern painted turtle, and one juvenile male yellow-spotted Amazon River turtle). Mean (sd) weight of the 25 red-eared sliders and one painted turtle was 436 (197) g, range 159–953 g; and mean (sd) straight carapace length (SCL) of these turtles was 14.7 (2.6) cm, range 9.8 to 19.3 cm. The Amazon River turtle weighed 1500 g, and SCL was not recorded. Results of preoperative physical examinations were unremark-able. Few turtles voided urine during manual attempts to empty the bladder.

FIG 4: Coelioscopic orchiectomy of a male red-eared slider turtle (Trachemys scripta elegans) using monopolar radiosurgery. (a) Monopolar radiosurgical endoscissors are used to transect the mesorchium of the left testis (T). (b) Surgical site (S) after excision of the testis with monopolar radiosurgical endoscissors. Left epididymis (E), left lung (L), left renal vein (V), left kidney (K); arrows indicate the yellow tissue of the left adrenal gland.

FIG 3: Coelioscopic orchiectomy of a male red-eared slider turtle (Trachemys scripta elegans) using a ligation clip. (a) Stainless steel ligation clip is placed across the mesorchium of the left testis (T). (b) Ligation clip secured across the mesorchium. (c) Cutting the mesorchium distal to the ligation clip with endoscissors. D: Ligation clip across the mesorchium remnant after excision of the testis. Lung (L), epididymis (E), colon (C), urinary bladder (U); arrows indicate the yellow tissue of the adrenal gland.




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In 22 cases, bilateral orchiectomy was performed through a single incision; five turtles required bilateral incisions (four red-eared sliders and the Amazon River turtle). Mean (sd) surgery time was 37 (11) minutes via unilateral incision, 58 (eight) minutes via bilateral inci-sions for red-eared sliders, and 135 minutes for the Amazon river tur-tle. Fifteen turtles were castrated using stainless steel clip ligation of the mesorchium followed by transection with endoscissors; 11 turtles were castrated using radiosurgical scissor transection only; and one turtle was castrated using both methods (radiosurgery ipsilaterally, ligation clip contralaterally due to difficulty with achieving radio-surgical clearance of the mesorchium from the adjacent colon). For red-eared sliders (the only species for which both surgical methods were used), mean (sd) surgery time using a unilateral incision and ligation clips was 31 (six) minutes (n=10); while mean (sd) surgery time using a unilateral incision and radiosurgical transection was 40 (10) minutes (n=10).

In all turtles, the testes were easily identified attached to the epididymis at the anterior extent of the kidney and the caudal extent of the lung (Fig 1). The adjacent adrenal gland, urinary bladder and colon could be easily identified (Figs 1–4). Testes were tan to yellow in colour and smooth. In red-eared sliders and the painted turtle, the tes-tes were approximately 0.5–1 cm in diameter, and were roughly ovoid to globoid. The mesorchium of these two species was clearly delineat-ed upon elevation of the testis, such that ligation and transection could be easily achieved. In general, only a single medium-sized ligation clip was needed to encompass the entire width of the mesorchium of these species (Fig 3). To access the contralateral testis, the endoscope was directed ventral to the colon, dorsal to the urinary bladder, and was used to elevate the colon dorsally to expose the testis. This often required several minutes of exploration. After grasping the contralat-eral testis with endoforceps, it was possible to protract it toward the surgeon, extending and exposing the mesorchium. However, less of the proximal extent of the contralateral mesorchium was visible com-pared with the ipsilateral mesorchium. Ligation and transection of the contralateral mesorchium often took longer than the ipsilateral mes-orchium, as surgeons took care to avoid adjacent structures while still completely excising the testis. It was generally faster to manage the

contralateral testis via ligation clips as the clip applicator could be used to simultaneously place the clip and dorsally retract the colon, such that the clip could be applied to the most proximal extent of the mes-orchium. With radiosurgery, greater care was required to allow current to be applied to only the mesorchium without touching the colon or other surrounding tissue. In cases where the contralateral testis could not be clearly visualised or manipulated, the unilateral approach was abandoned, and a bilateral approach was performed.

Testes of the Amazon River turtle were 4–5 cm in length, 1cm wide, roughly tubular in shape, and extended from the deep pelvic region medially toward the bridge of the shell laterally (Fig 5). The mesorchium of this species was attached to the ventral surface of the lung along much of its length (Fig 5c). These extensive mesorchium attachments made this surgery the most difficult and prolonged of those reported in the present study. Orchiectomy was achieved via sequential clip ligation and endoscissor transection starting at the cra-nial pole of the testis, progressing to the caudal pole. Bilateral incisions were elected for this turtle as the entirety of the contralateral testis could not be viewed from the initial incision.

In several cases, upon entry into the coelom, a thin membrane of peritoneum remained between the incision and the testis. It was deter-mined in these cases, that entry into the coelom had been made into the cranial extent of the retrocoelomic space at the lateral extent of the kidney (Hernandez-Divers 2004a). Solutions to this minor problem included sharp dissection of the membrane with endoscissors under endoscopic visualisation, or extension of the coelomic muscle incision cranially to allow for more routine entry.

All turtles recovered from anaesthesia. The three clinical cases remain alive and healthy at this time, one to three years postopera-tively. One experimental turtle was found dead outdoors 19 days after surgery during a period of extreme hot weather, but due to advanced autolysis, postmortem examination was not performed. Seven experi-mental turtles were found dead outdoors four months postoperatively, after an unusually severe autumn blizzard. Postmortem laparoscopy of these individuals revealed no evidence of testicular regrowth. Gross postmortem and histopathologic evaluation was conducted for one of these individuals and revealed mesenteric granulomas with

FIG 5: Coelioscopic view of the caudal (a), middle (b), and anterior (c) portions of the testis (T) of a yellow-spotted Amazon river turtle (Podocnemis unifilis). (d) Testes after excision. Epididymis (E), mesorchium (M), intestine (I), lung (L).




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intralesional bacteria. No testicular tissue was identified. One experi-mental turtle was found dead approximately one year postoperatively, but postmortem examination was not conducted.

During the summer, 14 months after surgery, a search of the outdoor pond revealed 14 of the expected 15 remaining experimen-tally neutered turtles. The fate of the one missing turtle could not be determined, but it is possible that it was present but not found, had escaped, or had died from predation or other causes. Eleven of the tur-tles were captured, definitively identified, and follow-up laparoscopy was performed. Five had been neutered using radiosurgery, five with ligation clips, and one with both methods. Physical examination of these turtles revealed no gross abnormalities. Follow-up coelioscopy revealed no testicular regrowth, and the surgical sites appeared to be healed (Fig 6). Biopsies were obtained from the remnant epididymis and ductus deferens of two turtles using size 5F cup biopsy forceps, and histologic examination revealed no pathology and no sperm.

DiscussionResults for the 27 turtles described in the present report suggest that coelioscopic orchiectomy is a practical and safe method for perform-ing elective orchiectomy in some turtle species. Although this study was not designed to specifically assess surgical incision healing rates, clinical examination of the skin incisions at the time of suture or sta-ple removal (4–8 weeks postoperatively) indicated good skin heal-ing. Such healing times are substantially shorter than healing times reported for turtles that have undergone shell osteotomy (12 weeks to one year; Hernandez-Divers 2004b, Mader and others 2006). In addition, although controlled studies are lacking, it is likely that this approach is less painful than osteotomy (Mader and others 2006).

A successful method of prefemoral unilateral orchiectomy with-out coelioscopy has been described for red-eared sliders (Kinney and others 2011); however, this method relies on the ability of the sur-geon to see and manipulate the gonad, using the naked eye, through a relatively small incision. It is likely that the excellent visualisation and magnification provided by coelioscopy offers benefits over non-coelioscopic methods in very large chelonians where the gonad may be very deep relative to the skin incision, in very small animals where the gonad may be difficult to locate and manipulate, and in species or individuals where the gonad is more extensive, such as the P unifilis in this study. In addition, in red-eared sliders in this study, bilateral orchi-ectomy was often possible through a unilateral incision, which based on our observations would be extremely difficult without coelioscopic guidance. Finally, in this study, many incisions were as small as 2 cm in length, compared with 5 cm incisions described in a previous report (Kinney and others 2011), which potentially may reduce surgical pain and complications. Objective determination of the benefits of coelio-scopic versus non-coelioscopic prefemoral orchiectomy in chelonians will require future controlled studies.

While phallectomy is expected to provide complete long-term insurance against fertility in chelonians, the presence of still func-tional testes and associated sperm production makes it at least pos-sible that fertilisation could occur via cloaca-to-cloaca contact, or via partial phallus regrowth. Evaluation of these possibilities will require long-term studies of phallectomised turtles. By contrast, it is likely that orchiectomy more definitively provides long-term contracep-tion. However, chelonian sperm are known to persist within the epididymis for at least four to six months (Lofts and Tsui 1977), and an exact time for complete cessation of fertility in turtles after being neutered cannot be determined from the study described here. The absence of sperm in the epididymis and ductus deferens of two turtles in this study, one year after being neutered, suggests that sperm deple-tion by one year postoperatively is likely.

Neutering of turtles causes reduced testosterone concentrations (Licht and others 1985), and thus could be useful in eliminating unde-sirable testosterone-induced behaviours in captive specimens. For example, some male turtles injure themselves, conspecifics, or other species during aggressive courtship and mating attempts, or during attempts to mate with inanimate objects (Innis and Boyer 2002). It is also possible that loss of male behaviours (eg, territoriality) or physical condition could be undesirable effects of being neutered, especially under free-ranging conditions. Long-term evaluations of the behav-ioural and physical effects of orchiectomy are warranted in these very long-lived species.

In this study, testes were successfully identified and excised using both unilateral and bilateral surgical approaches. However, locating and excising the contralateral testis via a unilateral approach was sometimes challenging, and in some individuals could not be accom-plished. Thus, for species in which this technique has not yet been attempted, species with elongated testes, and for surgeons who have not yet performed this technique, it may be more effective to utilise a bilateral approach initially. By planning a bilateral approach at the start, time spent unsuccessfully attempting to identify and excise the contralateral testis via unilateral approach will be eliminated. After gaining experience with the technique and familiarity with a par-ticular species via a bilateral approach, a unilateral approach could be attempted if it seems practical. It is unclear at this time whether alternative preoperative preparations (eg, longer fasting time, with-holding water, etc) could positively influence the ability to access the contralateral testis.

In one turtle in this study, the urinary bladder was perforated dur-ing initial entry into the coelom. In a pilot study of coelioscopic orchi-ectomy in turtles (data not shown) several cases of iatrogenic bladder perforation also occurred. The bladder of chelonians has osmoregula-tory capability, is very distensible, and in some species it is used to store water during periods of drought. Its thin, membranous wall may be mistaken for the peritoneal membrane and incised, especially when viewed through a small surgical incision. After encountering this problem in the pilot study, attempts were made to stimulate urina-tion prior to surgery, but were largely unsuccessful. Thus, subsequent surgical approaches were made very cautiously, and cystocentesis was utilised whenever the bladder or presumptive bladder was encoun-tered. Often, large volumes of urine were removed (eg, up to 10 per cent body weight). For future cases, it would be reasonable to use other methods to ensure that the urinary bladder is empty prior to surgery, such as ultrasound-guided cystocentesis in larger specimens, or per-cloaca urethral catheterisation via cloacoscopic guidance (Innis 2010). Notably, for the single case of bladder perforation in the present study, the bladder was surgically repaired, orchiectomy was aborted, and the patient remains alive over one year later at this time.

The confirmed mortalities seen in this study generally occurred months after surgery, and most were concentrated around an unex-pected, severe autumn storm, during which turtles were acutely exposed to unusually low temperatures. In the previously mentioned pilot study, a high postoperative mortality rate was seen beginning within 24 hours of surgery (data not shown). However, the pilot tur-tles had been acquired from a reptile supplier and acclimated for only several days prior to surgery. Histopathologic evaluation indicated that the pilot turtles were affected by pre-existing severe parasitism and bacterial infection, which likely contributed heavily to postoperative

FIG 6: Coelioscopic view of a previous left orhiectomy site (S), left epididymis (E), and left adrenal gland (arrows) of a male red-eared slider turtle (Trachemys scripta elegans) 14 months after coelioscopic castration using monopolar radiosurgical endoscissors.




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mortality. Serious disease outbreaks among groups of red-eared sliders from turtle farms and suppliers have been previously observed (Roberts and others 2006; Innis, personal observation). Turtles for subsequent study were acquired selectively by one author (RF), and acclimated for at least one month prior to surgery with the hope that they would be healthy specimens for research. Nonetheless, we cannot indisputably state that the mortalities in the present study were unrelated to surgery, and we recommend that additional studies are conducted in this regard. It is notable that mortalities were seen only in the research animals, while the clinical patients have fared well for one to three years to date. It is also notable that neither morbidity nor mortality was noted in 36 red-eared sliders that had unilateral orchiectomy in a previous study (Kinney and others 2011).

Although insufflation is often used for coelioscopic procedures in reptiles, visualisation of the testes in turtles generally does not require insufflation (Hernandez-Divers 2004a, Innis 2010), and orchiectomy in the present study was achieved without insufflation. In addition, orchiectomy did not require placement of endosurgical cannulae. Although cannulae may be used in chelonians, especially when instruments are placed through both prefemoral fossae, we found them unnecessary for the technique described in the present report. The prefemoral incision was sufficient to allow introduction of the endoscope, forceps, clip applicators and scissors through a single surgi-cal incision without the need for separate cannulae.

Various grasping forceps were used to hold and elevate the tes-tes. In general, we found that Babcock forceps with a ratchet closure mechanism provided the most consistent purchase on the testis, with the least tissue trauma, and resulted in fewer undesired releases of the tissue. On the contrary, when instruments without a ratchet closure were used, the testis often slipped out of the forceps during manipulation. Curved Kelly endoscopic forceps often crushed and avulsed fragments of the testis, leading to repeated grasping attempts. Thus, Babcock forceps with a ratchet mechanism are recommended for grasping and elevating the testis. For vascular clip application, standard clip applicators (ie, not endosurgical clip applicators) were found to be adequate for placement of the clips on the mesorchium. In general, surgical incisions were large enough to allow this standard instrument to enter the coelomic cavity adjacent to the other instru-ments. However, it is likely that in very large specimens, clip ligation of deeply located testes may require 10 mm endosurgical clip appliers.

Preliminary statistical analysis was explored to assess whether cor-relations could be made between surgical time and surgical method, weight and SCL. However, robust analysis was hindered by unequal distribution of weight and SCL between radiosurgical and ligation clip methods (despite randomisation of group assignment), and very limited numbers of turtles in the bilateral surgical group. In addition, surgical time likely varied based on the experience of the surgeon. Surgeries in the present study were performed by varying pairs of surgeons created from a group of eight veterinarians. The experience level of each veterinarian varied from new graduates, to residents, to veterinarians with years of chelonian endosurgical experience. We did not attempt to quantify differences in results among levels of experi-ence. However, our general impression was that even minimally expe-rienced veterinarians were able to safely and efficiently perform this procedure, especially when guided by a more experienced surgeon. In light of these limitations and confounding variables, only descriptive statistics are provided.

There are approximately 300 extant species of chelonians, and it is known that testicular anatomy is quite variable among species (Kuchling 1999, Innis and Boyer 2002). The three species described in this report represent only two chelonian families. In addition to spe-cies variation, there is seasonal and age-related variation in testicular morphology and function in turtles (Lofts and Tsui 1977, Kuchling 1999). Thus, clinicians should expect to encounter potentially complex situ-ations when attempting to neuter some chelonians, as seen with the

Amazon River turtle in this study. In a previous report, an attempt at coelioscopic orchiectomy of a Galapagos tortoise (Geochelone nigra) was mentioned briefly, and was reported to have failed (Rivera and others 2011). It is likely that additional experiences with a wider variety of species and wider variety of endosurgical equipment will lead to more refined methods of endosurgery for chelonians. In this regard, coelio-scopic orchiectomy appears to be a useful endosurgical model for the development of additional minimally invasive surgical techniques in chelonians.

AcknowledgementsWe thank Phil Blais, Patricia Casteel, Stephanie Dietzel, Scott Dowd, Deana Edmunds, Kelsey Ericksen, Kerri Forrester, Scott Fowler, Bridget Heath, Katie Kodzis, Johanna Mehia-Fava, Andrew Murphy, Marlaina Nelson, Jamie Pardito, Eric Payne, Stuart Ann Varner, Tina Wilkins, Greg Wolfus, VCA Westboro Animal Hospital, and the ani-mal care staff of the University of Georgia for assistance with sur-gical and postoperative care of the animals described herein. Emily Bauerenfeind assisted with image preparation. Nicole Gottdenker and Michael Garner performed histopathologic examinations.

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doi: 10.1136/vr.1014752013

2013 172: 526 originally published online April 4,Veterinary Record C. J. Innis, R. Feinsod, J. Hanlon, et al. and safely accomplished in cheloniansCoelioscopic orchiectomy can be effectively

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coelioscopic orchiectomy can be effectively and safely accomplished in chelonians

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