ANESTHESIA AND SURGERY PROTOCOLS FOR INTRA-ABDOMINAL TRANSMITTER PLACEMENT IN FOUR SPECIES OF WILD ARMADILLO.

The anatomy and physiology of armadillos make anesthetic procedures and the placement of telemetry devices challenging. From June 2011 to November 2019, a total of 73 free-living armadillos were captured and anesthetized in the Pantanal, Brazil. Giant (Priodontes maximus), six-banded (Euphractus sexcinctus), southern naked-tailed (Cabassous unicinctus), and nine-banded (Dasypus novemcinctus) armadillos were divided into two groups. In group 1, 30 armadillos were anesthetized for collection of biological samples, body measurements, and placement of a microchip tag. Anesthetic combination BDM was applied: butorphanol tartrate, detomidine hydrochloride, and midazolam hydrochloride, each at 0.1 mg/kg. In group 2, 43 armadillos received ketamine hydrochloride at 10 mg/kg 20 min after BDM injection, and intra-abdominal radio transmitters were surgically implanted. The transmitter was inserted freely into the abdominal cavity. Vital signs were monitored during anesthesia every 10 min and varied within species and between groups. Rectal temperature varied from 33.1 ± 1.36 to 35.34 ± 1.21°C, heart rate (beats/min) from 19 ± 2.14 to 84.71 ± 9.25, respiratory rate (breaths/min) from 11 ± 4.16 to 31 ± 2.82, and oxygen saturation values (SPO2%) from 84.17% ± 2.39 to 98% ± 1.20. Both groups received the antagonist combination NYF: naloxone hydrochloride (0.02 mg/kg), yohimbine hydrochloride (0.125 mg/kg), and flumazenil (0.01 mg/kg). Recovery varied according to intravenous or intramuscular injection from 2 ± 4 to 8.08 ± 2.93 min respectively. BDM protocol was considered satisfactory and provided enough time to complete the procedures (60 ± 85 to 133.20 ± 9.12 min) according to the species and group. Ketamine added to the BDM provided enough time and a surgical plane of anesthesia (97 ± 22 to 137 ± 39.5 min). The surgical procedure technique chosen did not appear to have a negative impact on armadillos studied. Implantable transmitters provide a cost-effective method for long-term monitoring of wild individuals.

Chemical Immobilization of Free-ranging Yellow Armadillos (Euphractus sexcinctus) for Implantation of Intra-abdominal Transmitters.

Free-ranging yellow armadillos (Euphractus sexcinctus) from the Brazilian Pantanal were captured for surgical implantation of intra-abdominal radio transmitters. During March 2014, 11 animals were chemically immobilized with a combination of intramuscular ketamine hydrochloride, xylazine hydrochloride, midazolam maleate, and atropine sulfate. The mean induction time and initial heart rate in males was higher than in females. The sex of armadillos did not affect the respiratory rate, which increased from the beginning to end of the monitoring time. The rectal temperatures of females remained almost unchanged, whereas the rectal temperatures of males suffered a slight drop through the procedure. The mean (±SD) total surgical time was 50±6.5 min, and the total anesthetic recovery time was 2.5±0.5 h. The armadillos were monitored for 24 h after surgery and released at their capture site. The anesthetic association was effective, promoting muscle relaxation and analgesia that allowed the performance of surgical procedures.