Resumo
Background: The Brazilian tapir (Tapirus terrestris), considered the largest land mammal in South America, is a vulnerable species in terms of its degree of conservation. In captivity, its health is evaluated through behavioral and physical observation and laboratory exams, and in some cases, chemical restraint, to reduce stress. Dissociative anesthetics and sedatives are used for the sedation of these animals, and few studies have reported the use of dexmedetomidine and its effects when associated with other drugs in chemical containment protocols; therefore, this work reports its use, in conjunction with ketamine and midazolam, in a young Brazilian tapir. Case: A male Brazilian tapir, male, weighing 89 kg, 1 and a half year old, housed at CETAS in Rio Branco, Acre, was chemically restrained with dexmedetomidine (7 µg/kg), ketamine (1.5 mg/kg), and midazolam (0.2 mg/kg) for venous blood collection, oral and rectal mucosal swabs, and microchipping. The protocol was administered intramuscularly to the right triceps brachii, after physical restraint. After 5 min of application, the animal assumed sternal recumbency and presented reflux. After 15 min, the patient was placed in the right lateral decubitus position. During collection, heart rate (48 ± 10 bpm), respiratory frequency (29 ± 1 mpm), rectal temperature (38.1 ± 0.18°C), oxyhemoglobin saturation (97 ± 1%), and electrocardiographic tracing were recorded. The tapir showed deep sedation, immobility, good muscle relaxation, discreet medial palpebral reflex, and bilateral rotation of the eyeball. After 40 min of protocol administration, sedative reversal was performed intramuscularly with 14 µg/kg atipamezole. Five min after administration, the tapir showed signs of mild sedation. After 10 min, he assumed the quadrupedal position, remained in this position for 8 min, and gently resumed the sternal decubitus. After only 20 min, he resumed the quadrupedal position, with mild ataxia and good muscular and conscious tone. After 50 min, the patient was discharged from anesthesia. Discussion: Domestic horses are phylogenetically close to tapirs, so the choice of drugs and doses of the protocol used was based on their use in horses, and on studies carried out with tapirs as well. Despite being docile and passive, the tapir was not conditioned and did not allow the manipulation and collection of samples collaboratively; therefore, it was chemically contained. The physical restraint performed did not generate satisfactory immobilization of the tapir, resulting in agitation and stress and causing the needle to break. The reflux presented by the tapir minutes after sedation and at recovery was induced by dexmedetomidine, and only the undigested banana pieces were offered to the animal. Reflux plus stress from extensive fasting and suboptimal physical restraint was responsible for the change in the tapir's eating behavior, with possible stress gastritis 24 h after chemical restraint. Only one study reported the use of dexmedetomidine in tapirs, associated with continuous infusions of ketamine, midazolam and guaiacol glyceryl ether for moderate to long-term field procedures. Sedative reversal of dexmedetomidine by atipamezole reduced the recovery time and the risk of death from cardiorespiratory depression. The anesthetic combination used was effective, promoting immobility, muscle relaxation, and stability of the physical parameters evaluated, with rapid and gentle induction and an adequate level of sedation for the objective, good sedative reversal, and anesthetic recovery.
Assuntos
Animais , Masculino , Perissodáctilos/fisiologia , Dexmedetomidina/administração & dosagem , Dexmedetomidina/análise , Animais Selvagens/fisiologiaResumo
Background: The brown bear (Ursus arctos) is considered one of the largest terrestrial carnivores, native from temperate forest regions of North America, Europe and Asia. In Brazil, they are founded in captivity and their safe capture and immobilization are obtained with one effective anesthesia for management and surgical and diagnostic procedures. Some anesthetic protocols are described for these purposes, however, there is a lack for data on the anesthetic and adverse effects they have on bears when used. The aim of this case is to report the use and effects of the association of dexmedetomidine with tiletamine and zolazepam in the chemical containment of a captive adult brown bear. Case: A 33-year-old female brown bear, weighing 100 kg, belonging to the Zoobotanic Park of Teresina, Piauí, Brazil, was chemically immobilized for an incisional biopsy of a cutaneous nodule with 1.0 cm diameter in the right face region. The anesthetic protocol included 6 µg/kg of dexmedetomidine associated with 3 mg/kg of tiletamine and zolazepam, administered intramuscularly by dart into the gluteal region of the right pelvic limb. The animal showed moderate ataxia at 5 min and assumed sternal decubitus 7 min after anesthetic administration. The bear's degree of sedation was considered adequate and safe to perform the biopsy at 10 min after administration. Heart rate (47 ± 3 bpm), respiratory rate (17 ± 2 mpm) and rectal temperature (38.7 ± 0.1ºC) were monitored. The bear remained immobile and unconscious throughout the procedure, with intense muscle relaxation, bilateral eyeball rotation, absent lateral palpebral reflex and mild medial reflex and without nystagmus. Complementary sedative doses were not necessary. At the beginning of anesthetic recovery, the bear received 6 µg/kg of atipamezole, intramuscularly. After 25 min of administration of atipamezole, the animal showed signs of recovery in the level of consciousness and reactivity to external stimuli, and assumed the quadrupedal position at 60 min after reverser application. Discussion: Even in captivity, the bears behavior is unpredictable and attack can occur, causing trauma or death to people. For this, the chemical immobilization is important to keep safety of everyone. This procedure was performed using blowgunassisted darts thrown by a staff member who had experience in using this method, who darted accurately and effectively. The latency time observed after administration of the anesthetic protocol used is similar to reported in other studies with bears that also received intramuscular dexmedetomidine and tiletamine and zolazepam and showed intense muscle relaxation and immobility. The doses used contributed to the absence of bradycardia and hypoventilation and, performing the procedure in the morning, when the temperature is milder in the city, minimized the chance of hyperthermia and thermal stress in the animal, not requiring body cooling. The use of dexmedetomidine in chemical containment protocols for short and minimally invasive procedures allows the subsequent use of its antagonist, atipamezole, contributing to a shorter recovery time, return of the animal's degree of consciousness and lower incidence of ataxia after assuming a quadrupedal position. The anesthetic protocol used was considered efficient, providing a quick and gentle chemical containment, adequate anesthetic plan and good anesthetic recovery in an adult brown bear from captivity.
Assuntos
Animais , Feminino , Tiletamina/administração & dosagem , Ursidae , Zolazepam/administração & dosagem , Dexmedetomidina/administração & dosagem , Imobilização/veterinária , Biópsia/veterinária , Anestésicos Combinados/análise , Animais SelvagensResumo
Background: Osteochondral knee failures are among the most common causes of disability among the elderly human population and animal athletes. The xenogeneic transplantation of mesenchymal stem cells is a questionable therapeutic alternative that, despite the low expression of Major Histocompatibility Complex type II by these cells, still has relevant uncertainties about the safety and clinical efficacy. The main objective of the present study was to investigate whether the xenogeneic transplantation of mesenchymal stem cells induces hyaline cartilage formation, without histopathological evidence of rejection, in osteochondral failures of goats.Materials, Methods & Results: Five female goats were used, submitted to three surgical osteocondral failures in the right knee, treated with xenogenic mesenchymal stem cells of dental pulp, xenogenic platelet-rich plasma and hemostatic sponge of hydrolyzed collagen, respectively. The lesions were evaluated after 60 days of treatment, aiming to identify the presence of hyaline cartilage or fibrocartilage and the subchondral bone pattern (regenerated or disorganized). Transplantation of xenogenic mesenchymal stem cells induced predominant formation of hyaline cartilage (P 0.05). Macroscopically, the lesions of the stem cell treated group showed formation of firm repair tissue, opaque staining, integrated with adjacent cartilage and with the failure filling almost completely. The groups treated with PRP and hemostatic sponge of hydrolyzed collagen presented, on average, partial filling of the lesion, with irregular shape and darkened coloration.[...]
Assuntos
Feminino , Animais , Cartilagem Articular/lesões , Cartilagem Hialina , Transplante de Células-Tronco Mesenquimais , Traumatismos do Joelho/induzido quimicamente , Traumatismos do Joelho/terapia , Cabras , Dasyproctidae , Modelos Animais de Doenças , Transplante Heterólogo/métodosResumo
Background: Osteochondral knee failures are among the most common causes of disability among the elderly human population and animal athletes. The xenogeneic transplantation of mesenchymal stem cells is a questionable therapeutic alternative that, despite the low expression of Major Histocompatibility Complex type II by these cells, still has relevant uncertainties about the safety and clinical efficacy. The main objective of the present study was to investigate whether the xenogeneic transplantation of mesenchymal stem cells induces hyaline cartilage formation, without histopathological evidence of rejection, in osteochondral failures of goats.Materials, Methods & Results: Five female goats were used, submitted to three surgical osteocondral failures in the right knee, treated with xenogenic mesenchymal stem cells of dental pulp, xenogenic platelet-rich plasma and hemostatic sponge of hydrolyzed collagen, respectively. The lesions were evaluated after 60 days of treatment, aiming to identify the presence of hyaline cartilage or fibrocartilage and the subchondral bone pattern (regenerated or disorganized). Transplantation of xenogenic mesenchymal stem cells induced predominant formation of hyaline cartilage (P < 0.05), with no histopathological evidence of inflammation when compared to the other treatments. Therapies with xenogeneic platelet-rich plasma and hemostatic sponge of hydrolyzed collagen induced greater formation of fibrocartilaginous cartilage, with no significant difference between them (P > 0.05). Macroscopically, the lesions of the stem cell treated group showed formation of firm repair tissue, opaque staining, integrated with adjacent cartilage and with the failure filling almost completely. The groups treated with PRP and hemostatic sponge of hydrolyzed collagen presented, on average, partial filling of the lesion, with irregular shape and darkened coloration.[...](AU)