Stephen J Hernandez-Divers

Publications of Stephen J Hernandez-Divers

• Investigation of shell disease in map turtles (graptemys spp.).

  Authors: Stephen J Hernandez-Divers, Patrick Hensel, Juliet Gladden, Sonia M Hernandez-Divers, Kurt A Buhlmann, Chris Hagen, Susan Sanchez, Kenneth S Latimer, Mary Ard, Alvin C Camus

  Journal of wildlife diseases. 08/2009; 45(3):637-52.

  Nineteen map turtles (Graptemys spp.) maintained under natural conditions were investigated because of chronic shell abnormalities. Animals were evaluated using a novel shell scoring system thatNineteen map turtles (Graptemys spp.) maintained under natural conditions were investigated because of chronic shell abnormalities. Animals were evaluated using a novel shell scoring system that divided the 54 scutes into six regions, with each region scored for lesion extent and severity, and summated to produce a total shell disease score (TSDS). Complete blood counts and various biochemistry analytes (total protein, albumin, globulin, urea, uric acid, 25-hydroxycholecalciferol, phosphorus, and ionized and total calcium) were measured. Under ketamine-medetomidine-morphine anesthesia, cytology tape strips and full thickness shell biopsies were collected aseptically for microbiologic, histologic (including scoring of biopsy quality), and ultrastructural evaluations. The TSDSs were low and ranged from 4 to 22 (median = 9) out of a possible score of 54. There were no correlations between TSDS and any hematologic or biochemistry parameter. The histologic quality of shell biopsies was good, and normal shell structure, by both light and electron microscopy, is described. Small clefts and pitting lesions were noted in 8/19 sections. There was no evidence of erosion, ulceration, inflammation, or infectious agents, but algae and diatoms were observed. Six biopsies yielded aerobic isolates (Chryseobacterium indologenes, Aeromonas hydrophila, Ralstonia pickettii, and Morganella morganii), whereas 11 shell samples grew various clostridial anerobes. No fungal organisms were cultured. Although the etiology of the lesions described remains unknown, the use of a scoring system in conjunction with full thickness biopsies is suggested to help standardize investigations into chelonian shell disease in the future.

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

  Authors: Stephen J Hernandez-Divers, Scott J Stahl, Raymond Farrell

  Journal of the American Veterinary Medical Association. 04/2009; 234(6):800-4.

  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 localOBJECTIVE: 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 Ringer's 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 Ringer's 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.

• Backyard chicken flocks pose a disease risk for neotropic birds in Costa Rica.

  Authors: Sonia M Hernandez-Divers, Pedro Villegas, Carlos Jimenez, Stephen J Hernandez-Divers, Maricarmen Garcia, Sylva M Riblet, C Ron Carroll, Barry M O'Connor, Julie L Webb, Michael J Yabsley, Susan M Williams, Susan Sanchez

  Avian diseases. 01/2009; 52(4):558-66.

  Pathogens of free-ranging chickens create a risk of disease for wild birds, some of which migrate to the United States, as well as potential economic losses for resource-poor farmers. Free-roamingPathogens of free-ranging chickens create a risk of disease for wild birds, some of which migrate to the United States, as well as potential economic losses for resource-poor farmers. Free-roaming backyard chickens are commonly kept in shade-grown coffee plantations, habitats that attract large numbers of wild birds. The husbandry and pathogen prevalence of backyard chicken flocks in San Luis, Costa Rica, were investigated. Based on serologic evidence, Newcastle disease virus, infectious laryngotracheitis virus, infectious bronchitis virus, chicken anemia virus, and infectious bursal disease virus, as well as both Mycoplasma gallisepticum and Mycoplasma synoviae, appear to be significant diseases of this population, and thus, we consider these backyard chickens potential reservoirs for these diseases. There was no evidence of avian influenza. Interviews, clinical examinations, and microscopic examination of tissues led us to believe that poxvirus is also a significant cause of morbidity and mortality in these chickens. We found that Escherichia coli isolates were resistant against tilmicosin, tetracycline, ampicillin, amoxicillin with clavulanic acid, ticarcillin, and cephalothin, and contained genes considered responsible for conferring tetracycline resistance. Additionally, although production was not measured, we suspect that husbandry and lack of preventative medicine are directly related to the diseases reported, all of which negatively affect production.

• Comparison between coelioscopy and coeliotomy for liver biopsy in channel catfish.

  Authors: S Shaun Boone, Stephen J Hernandez-Divers, Maryann G Radlinsky, Kenneth S Latimer, James L Shelton

  Journal of the American Veterinary Medical Association. 10/2008; 233(6):960-7.

  Objective-To evaluate endoscopic liver biopsy and compare that technique with a standard coeliotomy biopsy technique in fish. Design-Randomized controlled clinical trial. Animals-30 channel catfishObjective-To evaluate endoscopic liver biopsy and compare that technique with a standard coeliotomy biopsy technique in fish. Design-Randomized controlled clinical trial. Animals-30 channel catfish (Ictalurus punctatus). Procedures-10 fish were randomly assigned into control, coeliotomy, and coelioscopy groups. Anesthesia was performed with a recirculating anesthesia machine. Body weight, PCV, and total protein (TP) concentration in blood as well as plasma activities of aspartate aminotransferase, creatinine phosphokinase, lactate dehydrogenase, and sorbitol dehydrogenase were measured before and after surgery. Standard ventral coeliotomy or coelioscopy was performed, and the biopsy specimens were scored histologically. Results-Coeliotomy and coelioscopy procedures were well tolerated without acute deaths. Blood TP concentration and PCV decreased after surgery in the coelioscopy group because of intracoelomic fluid administration to aid visualization. Minor changes in activities for hepatic and muscular enzyme activities were apparent, but were not significantly different between the coelioscopy and coeliotomy groups. Coelioscopy and coeliotomy yielded biopsy specimens of similar diagnostic quality. However, coelioscopy permitted a more extensive evaluation of the viscera, and all 10 surgical wounds healed completely, compared with severe wound dehiscence in 3 of 10 fish that underwent coeliotomy. Conclusions and Clinical Relevance-Both coelioscopy and coeliotomy were capable of yielding antemortem liver biopsy specimens of diagnostic quality in catfish. Coelioscopy permitted a more detailed examination of the coelomic viscera through a smaller surgical incision, was less traumatic, and resulted in decreased wound dehiscence.

• Hematology of the Pascagoula map turtle (Graptemys gibbonsi) and the southeast Asian box turtle (Cuora amboinensis).

  Authors: David Perpiñán, Sonia M Hernandez-Divers, Kenneth S Latimer, Thomas Akre, Chris Hagen, Kurt A Buhlmann, Stephen J Hernandez-Divers

  Journal of zoo and wildlife medicine : official publication of the American Association of Zoo Veterinarians. 10/2008; 39(3):460-3.

  Turtle populations are decreasing dramatically due to habitat loss and collection for the food and pet market. This study sought to determine hematologic values in two species of turtles to helpTurtle populations are decreasing dramatically due to habitat loss and collection for the food and pet market. This study sought to determine hematologic values in two species of turtles to help assess health status of captive and wild populations. Blood samples were collected from 12 individuals of the Pascagoula map turtle (Graptemys gibbonsi) and seven individuals of the southeast Asian box turtle (Cuora amboinensis) from the Savannah River Ecology Laboratory (South Carolina, USA). The hematologic data included hematocrit, total solids, erythrocyte count, leukocyte count, and differential and percentage leukocyte counts. Low hematocrit values and high basophil counts were found in both species. The basophil was the most abundant leukocyte in the Pascagoula map turtle (median = 0.80 x 10(9)/L), whereas in the Southeast Asian box turtle the most abundant leukocyte was the heterophil (median = 2.06 x 10(9)/L).

• Evaluation of transcutaneous pulmonoscopy for examination and biopsy of the lungs of ball pythons and determination of preferred biopsy specimen handling and fixation procedures.

  Authors: Scott J Stahl, Stephen J Hernandez-Divers, Tanya L Cooper, Uriel Blas-Machado

  Journal of the American Veterinary Medical Association. 09/2008; 233(3):440-5.

  OBJECTIVE: To establish a safe and effective technique for the endoscopic examination and biopsy of snake lungs by use of a 2.7-mm rigid endoscope system. DESIGN: Clinical trial. ANIMALS: 17 adultOBJECTIVE: To establish a safe and effective technique for the endoscopic examination and biopsy of snake lungs by use of a 2.7-mm rigid endoscope system. DESIGN: Clinical trial. ANIMALS: 17 adult ball pythons (Python regius). PROCEDURES: The right lung of each anesthetized snake was transcutaneously penetrated at a predetermined site. Endoscopic lung examination was objectively scored, and 3 lung biopsies were performed. Tissue samples were evaluated histologically for diagnostic quality. One year later, 11 of the 17 snakes again underwent pulmonoscopy and biopsy; specimens were placed in various fixatives to compare preservation quality. All 17 snakes were euthanatized and necropsied. RESULTS: No major anesthetic, surgical, or biopsy-associated complications were detected in any snake. In 16 of 17 pythons, ease of right lung entry was satisfactory to excellent, and views of the distal portion of the trachea; primary bronchus; intrapulmonary bronchus; cranial lung lobe; and faveolar, semisaccular, and saccular lung regions were considered excellent. In 1 snake, mild hemorrhage caused minor procedural difficulties. After 1 year, pulmonoscopy revealed healing of the previous transcutaneous lung entry and biopsy sites. Important procedure-induced abnormalities were not detected at necropsy. Diagnostic quality of specimens that were shaken from biopsy forceps into physiologic saline (0.9% NaCl) solution before fixation in 2% glutaraldehyde or neutral-buffered 10% formalin was considered good to excellent. CONCLUSIONS AND CLINICAL RELEVANCE: By use of a 2.7-mm rigid endoscope, lung examination and biopsy can be performed safely, swiftly, and with ease in ball pythons. Biopsy specimens obtained during this procedure are suitable for histologic examination.

• Evaluation of an endoscopic liver biopsy technique in green iguanas.

  Authors: Stephen J Hernandez-Divers, Scott J Stahl, Michael McBride, Nancy L Stedman

  Journal of the American Veterinary Medical Association. 07/2007; 230(12):1849-53.

  OBJECTIVE: To establish a safe and effective endoscopic technique for collection of liver biopsy specimens from lizards by use of a 2.7-mm rigid endoscope system that is commonly available inOBJECTIVE: To establish a safe and effective endoscopic technique for collection of liver biopsy specimens from lizards by use of a 2.7-mm rigid endoscope system that is commonly available in zoologic veterinary practice. DESIGN: Prospective study. ANIMALS: 11 subadult male green iguanas (Iguana iguana). PROCEDURES: Each lizard was anesthetized, and right-sided coelioscopic examination of the right liver lobe and gallbladder was performed. Three liver biopsy specimens were collected from each lizard by use of a 2.7-mm rigid endoscope and 1.7-mm (5-F) biopsy forceps. Biopsy samples were evaluated histologically for quality and crush artifact. Ten days following surgery, all iguanas were euthanatized and underwent full necropsy examination. RESULTS: For all 11 iguanas, the right liver lobe and gallbladder were successfully examined endoscopically, and 3 biopsy specimens of the liver were collected without complications. Mean +/- SD durations of anesthesia and surgery were 24 +/- 7 minutes and 6.8 +/- 1.0 minutes, respectively. At necropsy, there was no evidence of trauma or disease associated with the skin or muscle entry sites, liver, or any visceral structures in any iguana. All 33 biopsy specimens were considered acceptable for histologic interpretation; in most samples, the extent of crush artifact was considered minimal. CONCLUSIONS AND CLINICAL RELEVANCE: By use of a 2.7-mm rigid endoscope, liver biopsy procedures can be performed safely, swiftly, and easily in green iguanas. Biopsy specimens obtained by this technique are suitable for histologic examination. For evaluation of the liver and biopsy specimen collection in lizards, endoscopy is recommended.

• Emergency care of reptiles.

  Authors: David Martinez-Jimenez, Stephen J Hernandez-Divers

  The veterinary clinics of North America. Exotic animal practice. 06/2007; 10(2):557-85.

  Most reptile emergencies are the result of improper husbandry and nutrition. Reptiles are good at masking disease, and owners, failing to recognize early signs of illness, only seek veterinaryMost reptile emergencies are the result of improper husbandry and nutrition. Reptiles are good at masking disease, and owners, failing to recognize early signs of illness, only seek veterinary assistance when issues are advanced and near terminal. The veterinarian should be familiar with reptile species-specific husbandry and nutritional requirements and basic clinical techniques. The same principles and techniques used in small animal medicine can be applied to reptile emergencies. This article reviews general emergency principles that apply to the reptilian patient and common emergency presentations. The main areas of discussion focus on cardiopulmonary resuscitation, fluid therapy, and analgesia.

• Endoscopic orchidectomy and salpingohysterectomy of pigeons (Columba livia): an avian model for minimally invasive endosurgery.

  Authors: Stephen J Hernandez-Divers, Scott J Stahl, G Heather Wilson, Michael McBride, Sonia M Hernandez-Divers, Tanya Cooper, Nancy Stedman

  Journal of avian medicine and surgery. 04/2007; 21(1):22-37.

  To evaluate a minimally invasive endosurgical system in birds, endoscopic orchidectomy and salpingohysterectomy were evaluated in 11 male and 14 female pigeons (Columba livia). Anesthesia wasTo evaluate a minimally invasive endosurgical system in birds, endoscopic orchidectomy and salpingohysterectomy were evaluated in 11 male and 14 female pigeons (Columba livia). Anesthesia was maintained by using isoflurane delivered by a pressure-cycle ventilator and produced good to excellent anesthesia during 96% of procedures. Endosurgery was performed with a 2.7-mm telescope system, 3-mm human pediatric laparoscopy instruments, and a 4.0-MHz radiofrequency device. Mean +/- SD surgery times for bilateral orchidectomy and salpingohysterectomy procedures were 39 +/- 18 minutes and 34 +/- 15 minutes, respectively. Procedures were generally straightforward, with any minor complications easily overcome. Surgical complications were generally minor, with mild hemorrhage and focal coagulative damage to the kidney being most common. All pigeons recovered quickly (20 +/- 11 minutes), with 95% displaying good to excellent recoveries. No birds exhibited any clinically apparent morbidity or mortality associated with endosurgery. At least 1 male and 1 female bird were subjected to elective euthanasia and necropsy on postoperative days 1, 3, 5, 10, 20, and 90 to determine the success and side effects of surgery. Gross and histologic abnormalities, when observed, were generally mild, with hemorrhage and partial necrosis of the cranial kidney present in 27% of males. Mild damage or hematoma associated with the left kidney was also reported in 28% of females. The surgical objectives were achieved in 23 of 25 pigeons. The 2 surgical failures (regenerated testes in a male and large oviductal remnant in a female) were attributed to endosurgical inexperience and occurred during the first procedures. Salpingohysterectomy does not appear to prevent ovarian development and ovulation in the pigeon, at least not during the first 3 postoperative months. Orchidectomy and salpingohysterectomy appear to be safe procedures when performed using appropriate equipment and techniques. Endosurgery offers a valuable, minimally invasive alternative to the standard coeliotomy techniques commonly used in birds.

• Renal diseases of reptiles.

  Authors: Paolo Selleri, Stephen J Hernandez-Divers

  The veterinary clinics of North America. Exotic animal practice. 02/2006; 9(1):161-74.

  Renal disease is one of the most common problems in reptilian medicine. Herbivorous species seem to be more susceptible than carnivores. The causation may be multifactorial, and the signs are oftenRenal disease is one of the most common problems in reptilian medicine. Herbivorous species seem to be more susceptible than carnivores. The causation may be multifactorial, and the signs are often nonspecific. Prevention is preferred to treatment, and a comprehensive health program, which includes quarantine, routine health screens during annual examinations, and necropsy examinations of all animals that die, is desirable.

• Paraphimosis and amputation in a Nile crocodile (Crocodylus niloticus).

  Authors: Felix Lankester, Stephen J Hernandez-Divers

  Journal of zoo and wildlife medicine : official publication of the American Association of Zoo Veterinarians. 01/2006; 36(4):698-701.

  A captive Nile crocodile (Crocodylus niloticus) developed recurrent episodes of paraphimosis over a 2-yr period, which eventually led to hemorrhage and obvious inflammation. Two months postsurgery,A captive Nile crocodile (Crocodylus niloticus) developed recurrent episodes of paraphimosis over a 2-yr period, which eventually led to hemorrhage and obvious inflammation. Two months postsurgery, the crocodile remained clinically normal.

• Cardiopulmonary effects of controlled versus spontaneous ventilation in pigeons anesthetized for coelioscopy.

  Authors: Gwenola Touzot-Jourde, Stephen J Hernandez-Divers, Cynthia M Trim

  Journal of the American Veterinary Medical Association. 12/2005; 227(9):1424-8.

  OBJECTIVE: To evaluate the cardiorespiratory effects of controlled versus spontaneous ventilation in pigeons anesthetized for coelioscopy. DESIGN: Prospective study. ANIMALS: 30 healthy adult pigeonsOBJECTIVE: To evaluate the cardiorespiratory effects of controlled versus spontaneous ventilation in pigeons anesthetized for coelioscopy. DESIGN: Prospective study. ANIMALS: 30 healthy adult pigeons (Columbia livia). PROCEDURE: During isoflurane anesthesia, 15 pigeons were allowed to breathe spontaneously (SP group) and 15 were mechanically ventilated (MV group) by use of a pressure-limited ventilator. In each group, cardiopulmonary variables (including end-tidal CO2 concentration [ETCO2]) were measured before (baseline), during, and after coelioscopy. An arterial blood sample was collected for blood gas analyses from each pigeon before coelioscopy and after the procedure, when the caudal thoracic air sac was still open. RESULTS: At baseline, hypoventilation was greater in the SP group than the MV group. Compared with the SP group values, ETCO2 overestimated PaCO2 to a greater degree in the MV group. Cardiovascular variables were not different between groups. After coelioscopy (when the air sac was open), PaCO2 had decreased significantly from baseline in the MV group. In the SP group, hypoventilation worsened despite an increase in respiratory rate. After coelioscopy, PaO2 in the SP group had decreased from baseline and was lower than PaO2 in the MV group; arterial blood pressure and heart rate in the MV group had decreased from baseline and were lower than values in the SP group. CONCLUSIONS AND CLINICAL RELEVANCE: In adult pigeons, controlled ventilation delivered by a pressure-limited device was not associated with clinically important adverse cardiopulmonary changes but may be associated with respiratory alkalosis and cardiovascular depression when air sac integrity has been disrupted.

• Anesthesia case of the month. Tachycardia.

  Authors: Erik H Hofmeister, Stephen J Hernandez-Divers

  Journal of the American Veterinary Medical Association. 10/2005; 227(5):718-20.

• Renal evaluation in the healthy green iguana (Iguana iguana): assessment of plasma biochemistry, glomerular filtration rate, and endoscopic biopsy.

  Authors: Stephen J Hernandez-Divers, Scott J Stahl, Nancy L Stedman, Sonia M Hernandez-Divers, Juergen Schumacher, Christopher S Hanley, Heather Wilson, Anand N Vidyashankar, Ying Zhao, Wilson K Rumbeiha

  Journal of zoo and wildlife medicine : official publication of the American Association of Zoo Veterinarians. 06/2005; 36(2):155-68.

  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 cellPlasma 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 micromol/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.

• Comparison of isoflurane and sevoflurane anesthesia after premedication with butorphanol in the green iguana (Iguana iguana).

  Authors: Sonia M Hernandez-Divers, Juergen Schumacher, Scott Stahl, Stephen J Hernandez-Divers

  Journal of zoo and wildlife medicine : official publication of the American Association of Zoo Veterinarians. 06/2005; 36(2):169-75.

  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 recordedThe 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.

• Undifferentiated sarcoma resolved by forelimb amputation and prosthesis in a radiated tortoise (Geochelone radiata).

  Authors: Kelleyerin Clabaugh, K Michelle Haag, Christopher S Hanley, Kenneth S Latimer, Stephen J Hernandez-Divers

  Journal of zoo and wildlife medicine : official publication of the American Association of Zoo Veterinarians. 04/2005; 36(1):117-20.

  An adult female, radiated tortoise (Geochelone radiata) presented with a grossly swollen left forelimb that restricted mobility and prevented limb withdrawal. Clinical pathology revealed leukopeniaAn adult female, radiated tortoise (Geochelone radiata) presented with a grossly swollen left forelimb that restricted mobility and prevented limb withdrawal. Clinical pathology revealed leukopenia (1.9 x 10(9)/L) and hyperproteinemia (69 g/L) that on protein electrophoresis was attributed to increased acute-phase proteins in the alpha fraction (26.4 g/L). Biopsy revealed a poorly differentiated soft tissue sarcoma. Surgical amputation at the proximal humerus was curative. To encourage postoperative mobility, a novel methylmethacrylate prosthesis, molded from a lubricated transected tennis ball, was adhered to the plastron using three cortical bone screws. This is the first recorded case of a sarcoma in the genus Geochelone.

• Endoscopic sex determination and gonadal manipulation in Gulf of Mexico sturgeon (Acipenser oxyrinchus desotoi).

  Authors: Stephen J Hernandez-Divers, Robert S Bakal, Brian H Hickson, Clarence A Rawlings, Heather G Wilson, MaryAnn Radlinsky, Sonia M Hernandez-Divers, Samuel R Dover

  Journal of zoo and wildlife medicine : official publication of the American Association of Zoo Veterinarians. 01/2005; 35(4):459-70.

  Seventeen Gulf of Mexico sturgeons (Acipenser oxyrinchus desotoi) underwent endoscopic sex determination, gonadal biopsy, and various reproductive surgeries as part of a conservation developmentSeventeen 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.

• Comparison of the effect of dipotassium ethylenediaminetetraacetic acid and lithium heparin on hematologic values in the green iguana (Iguana iguana).

  Authors: Christopher S Hanley, Stephen J Hernandez-Divers, Shay Bush, Kenneth S Latimer

  Journal of zoo and wildlife medicine : official publication of the American Association of Zoo Veterinarians. 10/2004; 35(3):328-32.

  We compared the effects of dipotassium ethylenediaminetetraacetic acid (EDTA) and lithium heparin on hematologic values of green iguanas (Iguana iguana). Thirty-two privately owned sibling iguanasWe compared the effects of dipotassium ethylenediaminetetraacetic acid (EDTA) and lithium heparin on hematologic values of green iguanas (Iguana iguana). Thirty-two privately owned sibling iguanas had blood drawn, and the sample was divided into three components: an EDTA tube, a heparin tube, and a nonanticoagulated blood smear. A full reptilian complete blood count was performed on each anticoagulated sample, and white blood cell (WBC) and leukocyte differential counts were performed on the whole-blood smears. Heparin and EDTA samples differed significantly in absolute values of thrombocytes, WBC, heterophils, and monocytes. The EDTA had no significant effect on the packed cell volume or plasma protein values, and the white blood count and differential counts produced with EDTA were more similar to those of the nonanticoagulated blood smear than were the counts produced with heparin.

• Nursing care of lizards.

  Authors: Michael McBride, Stephen J Hernandez-Divers

  The veterinary clinics of North America. Exotic animal practice. 06/2004; 7(2):375-96, vii.

  This article should introduce to the veterinary staff some of the basic information that is required to provide high-quality medicine to lizards. This article begins with a brief introduction toThis article should introduce to the veterinary staff some of the basic information that is required to provide high-quality medicine to lizards. This article begins with a brief introduction to lizards and their husbandry, including caging, lighting, humidity, and diet.Making appointments for lizards, taking a history, manual restraint,venipuncture, fecal sampling, catheterization, medications,administering fluids, giving injections, radiology, and anesthesia are all detailed for veterinary technicians and veterinary animal care staff. Each section details differences between lizards and typical mammalian patients while trying to emphasize the common approach to both groups of animals.

• Green iguana nephrology: a review of diagnostic techniques.

  Authors: Stephen J Hernandez-Divers

  The veterinary clinics of North America. Exotic animal practice. 02/2003; 6(1):233-50.

  There is still much to learn about renal physiology and pathophysiology in reptiles. In the case of the green iguana, initiating causes are often inferred from poor husbandry and nutrition, orThere is still much to learn about renal physiology and pathophysiology in reptiles. In the case of the green iguana, initiating causes are often inferred from poor husbandry and nutrition, or extrapolated from histopathologic interpretations made late in the course of the disease, or at postmortem. The link between parathyroid hormone and renal disease in humans has been well documented and, given the high prevalence of clinical (and subclinical) secondary nutritional hyperparathyroidism in iguanas, this certainly warrants further investigation in saurians [31,32,34,35]. Apart from hyperparathyroidism, chronic water deprivation also appears to be a common historic factor. As a foliovore originating from the high humidity rain forests of central and South America, water recovery is not considered to be an adaptive stress in Iguana iguana, and therefore, renal anatomy and physiology are considered to be non-specialized compared to more arid or aquatic reptiles [21]. These arboreal lizards do not voluntarily drink from open water but instead imbibe rain or dew droplets from foliage [2]. Maintaining such a species in low relative humidity with a water bowl from which to drink is likely to both increase insensible water losses and interfere with normal water intake. Appropriate therapeutic decisions (including euthanasia) can only be made following an accurate diagnosis. To date, our diagnoses are based largely upon the structural evaluations of renal histopathology, and renal biopsy remains our most useful tool. However, in the future it may become possible to evaluate renal function by quantifying glomerular filtration rate, proximal tubular secretion, or functional renal mass. Glomerular filtration rate may be estimated by measuring the rate of glomerular clearance of substances from the blood (e.g., iohexol). Phenolsulphonphthalein assays may offer an insight into proximal tubule secretion and renal blood flow.