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

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.     

Cystic thyroid and parathyroid lesions in cats

Reports of cystic thyroid and parathyroid masses in cats are uncommon. Herein, the authors describe a series of four cats with cystic ventral cervical lesions, among them thyroid cyst (n=1), thyroid cystadenoma (n=2), and parathyroid adenocarcinoma (n=1). Presentations ranged from completely asymptomatic cervical swellings to signs related to local compression of adjacent structures (e.g., trachea). Ultrasonographic evaluation was helpful in localization of the mass in two cases. Hormone analysis and concentration of cystic fluid were performed in one cat. Surgical excision was performed successfully in three cases. Histopathological examination was performed in all four cases. Long-term prognosis was excellent for those cases in which follow-up was available.     

Use of a continuous, local infusion of bupivacaine for postoperative analgesia in dogs undergoing total ear canal ablation

OBJECTIVE: To determine whether addition of a continuous, local infusion of bupivacaine would improve postoperative analgesia in dogs undergoing total ear canal ablation. DESIGN: Randomized controlled trial. ANIMALS: 16 dogs undergoing total ear canal ablation (12 unilaterally and 4 bilaterally with > 1 month between procedures). PROCEDURE: Dogs were randomly allocated to receive morphine (0.25 mg/kg [0.11 mg/lb]) at the end of the procedure (10 procedures) or morphine and a continuous, local infusion of bupivacaine (0.13 to 0.21 mg/kg/h [0.06 to 0.1 mg/lb/h]; 10 procedures). Dogs were observed for 48 hours after surgery. Additional doses of morphine were administered up to every 4 hours in dogs with signs of severe pain. RESULTS: Temperament, sedation, analgesia, and cumulative pain scores were not significantly different between groups any time after surgery. Recovery score was significantly higher for dogs that received bupivacaine than for control dogs 2 hours after extubation but not at any other time. Serum cortisol concentration was not significantly different between groups at any time but, in both groups, was significantly increased at the time of extubation, compared with all other observation times. Total number of additional doses of morphine administered was not significantly different between groups. Bupivacaine was not detected in the plasma of any of the dogs that received the local bupivacaine infusion. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that addition of a continuous, local infusion of bupivacaine did not significantly increase the degree of postoperative analgesia in dogs that underwent total ear canal ablation and were given morphine at the end of surgery.     

Multiple dose pharmacokinetics and acute safety of piroxicam and cimetidine in the cat

The purpose of this study was to evaluate the multiple dose pharmacokinetics and acute safety of piroxicam and cimetidine alone and in combination in cats. Seven healthy cats were included in this randomized-crossover study. The cats were assigned to groups designated to receive cimetidine alone (15 mg/kg, p.o., q12 h), piroxicam alone (0.3 mg/kg, p.o., q24 h), and piroxicam combined with cimetidine (both at aforementioned doses). The cats were dosed for 10 days followed by at least a 2-week washout period between trials. Serial blood samples were collected following the first and last doses and analyzed utilizing a high-performance liquid chromatography with mass spectrometry detection (LC/MS) assay. Pharmacokinetic parameters were determined using noncompartmental analysis. Endoscopic evaluation of the gastric mucosa was performed and serum urea nitrogen (SUN), creatinine, alkaline phosphatase (ALP), and alanine transaminase (ALT) activities were evaluated. There were not a clinically relevant difference between the pharmacokinetic parameters of piroxicam administered alone or in combination with cimetidine after either the first or last dose. Gastric ulcers were not observed in any cats although gastric erosions were. The SUN, creatinine, ALP, and ALT activities remained within reference ranges for all cats. It appears that once daily, short-term use of piroxicam alone and in combination with cimetidine in cats is relatively safe based on the parameters evaluated in this study. However, further studies are necessary to determine the long-term gastrointestinal safety of piroxicam.     

RADIOGRAPHIC AND ULTRASONOGRAPHIC FINDINGS OF LIVER LOBE TORSION IN A DOG

A twelve-year-old neutered male beagle presented for a cranial abdominal mass. The results of physical examination, laboratory tests, radiography, and ultrasonography are presented. A torsion of the quadrate lobe of the liver was diagnosed at surgery and confirmed by histopathology. A brief discussion of liver lobe torsion is presented.     

Thoracoscopic visualization and ligation of the thoracic duct in dogs

OBJECTIVE: To develop a technique for thoracoscopic visualization and ligation of the thoracic duct in dogs. STUDY DESIGN: In vivo experimental study. ANIMALS: Five mature, healthy dogs. METHODS: Dogs were normal based on physical examination, negative occult heartworm test, normal complete blood count and biochemical profile, and normal thoracic radiographs. The dogs were anesthetized, and a ventral midline laparotomy was performed for catheterization of a mesenteric lymphatic. Lymphangiography was performed to determine thoracic duct anatomy. Thoracoscopy was performed in the caudal, right hemithorax after single lung intubation or bronchial blockade. At least two 10-mm clips were placed across the thoracic duct in each dog. Lymphangiography was repeated to assess duct ligation. If complete duct occlusion was not achieved, thoracoscopy was repeated for additional clip placement. After surgery the dogs were euthanatized, and necropsies were performed. RESULTS: Lymphangiography showed that multiple branches of the thoracic duct were present in every dog; bilateral thoracic duct branches were most common. Thoracoscopic identification and ligation of the thoracic duct was successful in all five dogs. Two dogs required a second thoracoscopic procedure to completely occlude flow of contrast through the thoracic duct. Surgery time for thoracoscopy averaged 59 plus minus 9.6 minutes. Retroperitoneal contrast accumulation after thoracic duct ligation occurred in two dogs. One dog required bilateral pulmonary ventilation. CONCLUSION: Thoracoscopy can be used to visualize the thoracic duct for ligation in normal dogs. CLINICAL RELEVANCE: Thoracoscopic ligation of the thoracic duct may be a therapeutic option for management of chylothorax in dogs.     

Transnasal laryngoscopy for the diagnosis of laryngeal paralysis in dogs

Four dogs with clinical signs of laryngeal paralysis and three normal dogs were evaluated with transnasal laryngoscopy. Six of these dogs subsequently underwent standard laryngoscopy. For transnasal laryngoscopy, a video endoscope was passed through the left nasal passage after intramuscular sedation and topical anesthesia. The laryngeal opening was observed during spontaneous ventilation. Laryngeal paralysis was diagnosed in four dogs and was confirmed with traditional laryngoscopy in three dogs. Normal motion of the arytenoid cartilages was present in the other three dogs; however, two required mechanical stimulation of the laryngeal mucosa for full evaluation. Transnasal laryngoscopy provided a means for diagnosing laryngeal paralysis in dogs without general anesthesia.