Stephen J. Hernandez-Divers

An endoscopic method for identifying sex of hatchling Chinese box turtles and comparison of general versus local anesthesia for coelioscopy

OBJECTIVE To establish a safe and effective endoscopic method for visualizing the gonads and identifying the sex of hatchling Chinese box turtles and to compare the effects of general versus local anesthesia during coelioscopy. DESIGN Clinical trial. ANIMALS 58 hatchling Chinese box turtles (Cuora flavomarginata). PROCEDURES Turtles were randomly assigned to be anesthetized with a mixture of ketamine, medetomidine, and morphine (n = 29) or to receive local anesthesia with lidocaine in the prefemoral region (29). Coelioscopy was performed with a rigid 1.9- or 2.7-mm telescope following insufflation with sterile lactated Ringers solution. Ease of endoscopic sex identification and quality of anesthesia were scored. Body weights were recorded before and 7 and 14 days after surgery. RESULTS Gonads were easily visualized and sex was easily identified in all 58 turtles without complications. Endoscopy scores and pre- and postoperative weights did not differ significantly between groups. However, anesthesia scores were significantly worse for animals that received local anesthesia alone, compared with those that underwent general anesthesia. All anesthetized turtles recovered within 21 minutes after administration of the reversal agents, atipamezole and naloxone. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that coelioscopy with a rigid endoscope and lactated Ringers solution for insufflation was a safe and effective method for identifying the sex of hatchling Chinese box turtles. General anesthesia was effective and effects were rapidly reversible; local anesthesia with lidocaine alone was considered insufficient for coelioscopy.

Angiographic, Anatomic and Clinical Technique Descriptions of A Subcarapacial Venipuncture Site for Chelonians

ABSTRACT A novel technique for chelonian venipunture is described. Angiographic studies using radio-opaque iohexol, static radiography, and video fluoroscopy were undertaken in several chelonian species. Latex injected dissections were also performed to confirm the vascular anatomy. These studies indicate that a clinically useful venipuncture site is present in the anterior dorsal midline at the junction of the common intercostal veins and the caudal cervical branch of the external jugular veins, located just craniad of the last mobile cervical vertebra.

Prevalence of mycoplasmas in eggs from birds of prey using culture and a genus-specific mycoplasma polymerase chain reaction

Mycoplasmas are commensals and pathogens of different avian species, especially poultry and passeriforms. The role of mycoplasmas in raptors has not yet been completely determined, and especially not the possibility of vertical transmission. Therefore 424 raptor eggs were examined for the occurrence of mycoplasmas using culture, and 155 of these eggs with a Mycoplasma genus-specific polymerase chain reaction (PCR) assay. This PCR was tested for its sensitivity and specificity, especially for use in a bird population of unknown mycoplasma status (prevalence and species). The size of the amplified PCR product was large (1013 base pairs) to enable use of the product for species differentiation by sequencing. Culture and PCR yielded only one positive result, in an egg of a Northern Goshawk (Accipiter gentilis). The isolate was identified as Mycoplasma lipofaciens using an immunobinding assay, as well as by sequencing part of its 16S rRNA gene.

ENDOSCOPIC SEX DETERMINATION AND GONADAL MANIPULATION IN GULF OF MEXICO STURGEON (ACIPENSER OXYRINCHUS DESOTOI)

Abstract Seventeen Gulf of Mexico sturgeons (Acipenser oxyrinchus desotoi) underwent endoscopic sex determination, gonadal biopsy, and various reproductive surgeries as part of a conservation development plan. The fish were anesthetized with tricaine methanesulfonate (MS-222) buffered with sodium bicarbonate and maintained on a recirculating water anesthesia circuit. A 6-mm Ternamian EndoTip Cannula, placed through the ventral midline, midway between pectoral and pelvic fins, permitted the introduction of a 5-mm telescope. Swim bladder aspiration and CO2 insufflation of the coelomic cavity provided excellent observation. Second and third cannulae were placed under direct visual control, lateral and cranial or caudal to the telescope cannula. Sex determination was successfully performed in all fish; however, five of 17 sturgeons (29%) required endoscopic gonadal biopsy to confirm sex. Bilateral ovariectomy or orchidectomy was successfully performed in three males and four females. Unilateral ovariectomy and bilateral ligation of the müllerian ducts using an extracorporeal suturing technique was accomplished in an additional three females. No apparent morbidity was associated with the anesthesia or endoscopic surgery in any fish. The ability to safely perform minimally invasive reproductive surgery in fish may have important management and conservation benefits.

RENAL EVALUATION IN THE HEALTHY GREEN IGUANA (IGUANA IGUANA): ASSESSMENT OF PLASMA BIOCHEMISTRY, GLOMERULAR FILTRATION RATE, AND ENDOSCOPIC BIOPSY

Abstract Plasma biochemistry, iohexol clearance, endoscopic renal evaluation, and biopsy were performed in 23 clinically healthy 2-yr-old green iguanas (Iguana iguana). Mean (±SD) values for packed cell volume (30 ± 3%), total protein (62 ± 7 g/L, 6.2 ± 0.7 g/dl), albumin (25 ± 2 g/L, 2.5 ± 0.2 g/dl), globulin (37 ± 6 g/L, 3.7 ± 0.6 g/ dl), total calcium (3.0 ± 0.2 mmol/L, 12.0 ± 0.7 mg/dl), ionized calcium (1.38 ± 0.1 mmol/L), phosphorus (1.32 ± 0.28 mmol/L, 4.1 ± 0.9 mg/dl), uric acid (222 ± 100 μmol/L, 3.8 ± 1.7 mg/dl), sodium (148 ± 3 mmol/L or mEq/ L), and potassium (2.6 ± 0.4 mmol/L or mEq/L) were considered within normal limits. Values for urea were low (<1.4 mmol/L, <4 mg/dl) with 70% of samples below the detectable analyzer range. After the i.v. injection of 75 mg/ kg iohexol into the caudal (ventral coccygeal or tail) vein, serial blood collections were performed over 32 hr. Iohexol assays by high-performance liquid chromatography produced plasma iohexol clearance graphs for each lizard. A three-compartment model was used to fit area under the curve values and to obtain the glomerular filtration rate (GFR) using regression analysis. The mean GFR (SD) was 16.56 ± 3.90 ml/kg/hr, with a 95% confidence interval of 14.78–18.34 ml/kg/hr. Bilateral endoscopic renal evaluation and biopsy provided tissue samples of excellent diagnostic quality, which correlated with tissue harvested at necropsy and evaluated histologically. None of the 23 animals demonstrated any adverse effects of iohexol clearance or endoscopy. Recommended diagnostics for the evaluation of renal function and disease in the green iguana include plasma biochemical profiles, iohexol clearance, endoscopic examination, and renal biopsy.

A Survey of Selected Avian Pathogens of Backyard Poultry in Northwestern Ecuador

Abstract As part of a larger ecologic research project and to collect disease prevalence information on backyard chicken flocks in northwestern Ecuador, 100 randomly selected birds from 10 flocks were examined, and blood, fecal, and ectoparasite samples were collected. The owners of the flocks were surveyed regarding flock management and disease history. Mean flock size was 20 birds (range, 1–75), and birds were kept for eggs and meat for either domestic consumption or local sale. Vaccination rates were low, with most owners (8 of 10) not vaccinating at all and some (2 of 10) vaccinating with one product either sporadically (1 of 10) or annually (1 of 10). None of the owners treated their chickens for parasites. Mortality rates of offspring were reported as high as 50% (range, 35%–50%) per flock. Deaths were associated with diseases described by owners as causing neurologic signs, sudden death, or respiratory problems. In addition, owners described epizootics of wartlike seasonal skin lesions, presumably but not confirmed as avian pox. Results of commercial enzyme-linked immunosorbent assays on serum samples showed that birds had antibodies against infectious bursal disease virus (100%), Newcastle disease virus (97%), avian encephalomyelitis virus (92%), chicken anemia virus (90%), infectious bronchitis virus (85%), Mycoplasma gallisepticum (73%), and Mycoplasma synoviae (68%). Although 11% of birds showed the presence of antibodies for avian influenza, antibody levels were low in all but 4 birds. Most birds (90%) had feather mite infestations. Results of necropsy and fecal examinations found low levels of internal parasitism, with cestodes and ascarids identified as the most prevalent endoparasites. Ectoparasites identified were Dermanyssus gallinae and Ornithonyssus bursa. The poultry diseases to which sampled chickens had been exposed are likely the cause of the high mortality rate reported by flock owners. In these backyard poultry flocks in Ecuador, preventive medicine protocols that provide realistic cost-benefit advantages should be implemented. Because wild birds are susceptible to some poultry diseases, free-roaming chickens might be potential vectors of pathogens that could affect wild birds.

Minimally Invasive Endoscopic Surgery of Birds

Abstract Endoscopy has proven to be an important diagnostic tool for avian veterinarians to observe and biopsy internal structures. To date, most of the described endoscopic procedures are single-entry techniques. The use of miniature endoscopic equipment has been pioneered in human pediatric laparoscopy, and many of these techniques can be used in avian medicine. The addition of a second and third port using 2.5- or 3.5-mm cannulae has facilitated the use of 2- or 3-mm instruments within the avian coelom. Triangulation of various instruments coupled with radiosurgical hemostasis has made several endoscopic procedures possible, including salpingohysterectomy and orchidectomy. In addition, endoscope-assisted, minimally invasive procedures, including enterotomy, enterectomy, cloacopexy, and pneumotomy, may be initiated internally and completed by standard surgical techniques. The advent of minimally invasive endoscopic surgery offers important benefits, including rapid and accurate diagnosis, reduced need for an extensive coeliotomy, reduced surgical stress, improved pulmonary function, more stable anesthesia, and reduced surgical and hospitalization periods.

PULMONARY CANDIDIASIS CAUSED BY CANDIDA ALBICANS IN A GREEK TORTOISE (TESTUDO GRAECA) AND TREATMENT WITH INTRAPULMONARY AMPHOTERICIN B

Abstract An adult female Greek tortoise (Testudo graeca) presented with dyspnea, lethargy, and anorexia. Severe unilateral pulmonary candidiasis was diagnosed and confirmed by histologic and microbiologic evaluations. Initial treatment with ketoconazole resulted in plasma elevations of aspartate aminotransferase, lactate dehydrogenase, and bile acids consistent with imidazole-induced hepatotoxicity. Plasma chemistry abnormalities resolved upon withdrawal of the drug. Temporary osteotomy permitted access to the diseased lung and facilitated intrapulmonary catheterization. Intrapulmonary amphotericin B therapy at 0.1 mg/kg s.i.d. for 34 days proved to be both safe and effective in this case.

COMPARISON OF ISOFLURANE AND SEVOFLURANE ANESTHESIA AFTER PREMEDICATION WITH BUTORPHANOL IN THE GREEN IGUANA (IGUANA IGUANA)

Abstract The anesthetic and cardiopulmonary effects of butorphanol followed by sevoflurane or isoflurane were compared in 23 male green iguanas (Iguana iguana). Heart and respiratory rates were recorded before administration of butorphanol (2 mg/kg i.m.) and at 30 min after premedication. Anesthesia was induced in 12 iguanas (group 1) with isoflurane (5%) and in 11 iguanas (group 2) with sevoflurane (7%). Heart rate, relative arterial oxygen hemoglobin saturation (SpO2), and end-tidal CO2 concentrations (EtCO2) were measured every minute for the first 5 min and every 5 min thereafter. Arterial blood gas parameters were determined at 10 and 40 min after induction. Thirty minutes after butorphanol administration, no significant changes in heart and respiratory rate were seen as compared with baseline values. Quality and time to induction were superior with butorphanol–sevoflurane (6 ± 3 min) than with butorphanol– isoflurane (9 ± 4 min). Vaporizer settings during maintenance ranged between 1–3% and 2–4%, respectively. No significant differences in heart rate were noted between groups. In the sevoflurane group, SpO2 values were >90% throughout. Although SpO2 values were <90% at 20, 25, and 30 min in the isoflurane group, no significant differences in SpO2 values were seen over time and between groups. A significant decrease in EtCO2 with time was present in both groups, with no significant differences between the groups. At 10 and 40 min, arterial blood oxygen saturation values were >90% in both groups and no significant differences were noted with time and between groups. Recovery time was significantly longer in the butorphanol–isoflurane group (35 ± 27 min) than in the butorphanol–sevoflurane group (7 ± 4 min). The cardiopulmonary effects of butorphanol–isoflurane and butorphanol–sevoflurane assessed in this study are similar, and both inhalants appear to be safe and effective for induction and maintenance in the green iguana.

Ultrasonographic appearance of the coelomic cavity in healthy green iguanas

OBJECTIVE To describe the ultrasonographic appearance of the coelomic cavity in healthy green iguanas. DESIGN Cross-sectional study. ANIMALS 26 healthy green iguanas (20 males and 6 females). PROCEDURES For coelomic ultrasonography, animals were physically restrained in dorsal recumbency by an assistant; chemical restraint was not used. Qualitative and quantitative observations were recorded. RESULTS Structures that could be visualized in all animals included the heart and cardiac chambers; liver; caudal vena cava; hepatic veins; portal vein; gallbladder; pyloric portion of the stomach; and, when distended, urinary bladder. Visualization of the kidneys was poor. The spleen could be identified in 17 animals, and the gonads could be identified in 22, but were most easily identified in males evaluated during November (ie, during the breeding season); no females were evaluated during the breeding season. Physiologic enlargement of the testes yielded an acoustic window for the spleen by displacing overlying intestine. Anechoic, free coelomic fluid was identified in 3 animals. Measurements of overall cardiac size, ventricular wall thickness, gallbladder size, thickness of the pyloric portion of the stomach, and splenic size were obtained. Only ventricular wall thickness was significantly correlated with body weight. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that ultrasonography allowed examination of most coelomic structures in green iguanas. The procedure was easily performed and was well tolerated in conscious animals.