EVALUATION OF A COMBINATION OF TILETAMINE-ZOLAZEPAM, MEDETOMIDINE, AND AZAPERONE WITH NASAL OXYGEN SUPPLEMENTATION FOR THE IMMOBILIZATION OF CAPTIVE CHACOAN PECCARIES (CATAGONUS WAGNERI) IN THE CHACO REGION OF PARAGUAY.

A combination of tiletamine-zolazepam, medetomidine, and azaperone was used to immobilize captive Chacoan peccaries (Catagonus wagneri) for health assessments and biological sample collection at the Centro Chaqueño para la Conservación e Investigación (CCCI) in the Paraguayan Chaco during July in 2017 and 2018. In total, 83 peccaries kept in 0.25-1.50 hectare enclosures were immobilized via dart-administered anesthetic. Mean animal weight was 33.89±3.74 kg (standard deviation; n=77). The mean intramuscular (IM) anesthetic drug and dosages were 0.03±0.00 mg/kg of medetomidine, 0.91±0.10 mg/kg of Zoletil 50 (tiletamine-zolazepam), and 0.30±0.03 mg/kg azaperone. The mean time to recumbency after darting was 6.07±2.65 min. The mean time to reach the anesthetic plane postdarting was 10.00±2.00 min. Muscle relaxation was adequate to allow minor veterinary procedures. A mean dosage of 0.15±0.02 mg/kg of atipamezole was given IM to reverse the medetomidine. Recoveries were smooth and animals were standing by 59.17±30.18 min postreversal. Full recovery and release back to enclosures occurred 90±30 min postreversal. A single dose of this drug combination provided adequate anesthesia for 88% of adult Chacoan peccaries; 12% needed a supplemental dose of tiletamine-zolazepam because of failure to receive the full dose from the anesthetic dart. Sex and age did not impact the dosage required to achieve immobilization. Confinement during recovery from anesthesia is required with this protocol. Aside from mild hypoxemia, no adverse effects from anesthesia were observed. However, oxygen supplementation as a part of this protocol is recommended to support circulatory and respiratory capacity.

Semen analysis parameters from a captive population of the endangered Chacoan peccary (Catagonus wagneri) in Paraguay.

Baseline information about the reproductive physiology of an endangered species is vital to captive breeding programs. This study analyzed reproductive parameters from eleven captive Chacoan peccaries (Catagonus wagneri) (mean age: 10.5 ±â€¯1.2 years old) in Paraguay. After immobilization, testis length, width and firmness (hard to flaccid, 1-3) were assessed, followed by electroejaculation and analysis of semen. Samples were examined for percentage and progressive motility, total cell count, percentage live spermatozoa and morphology. Mean (±SEM) testis volume and firmness were 24.7 ±â€¯1.8 cm3 and 2.1 ±â€¯0.1, respectively. Mean ejaculate volume was 2.9 ±â€¯0.7 ml with a pH of 7.7 ±â€¯0.3. Few male peccaries had motile spermatozoa (n = 5/9) with a mean percentage and progressive motility of 18.3 ±â€¯8.5% and 0.6 ±â€¯0.3, respectively. The mean percentage of live spermatozoa was 25.1 ±â€¯5.6%. Male peccaries had a low percentage of normal spermatozoa (12.4 ±â€¯2.5%). The mean total count of spermatozoa per ejaculate was also quite low at 1.58 ±â€¯1.01 million total spermatozoa per ejaculate. Spermatozoa defects were predominantly primary (77.7%) with the most common spermatozoa defects being tapered head (19.0 ±â€¯7.4%), diadem/crater (17.7 ±â€¯2.8%), and excess residual cytoplasm (9.6 ±â€¯2.5%). Male age was not correlated with semen parameters (percent live: r=-0.19; motility percentage: r = 0.01; percent normal spermatozoa: r = 0.38; total count: r = 0.29; p>0.05). Evaluation of additional males from this population as well as other captive populations at various time points during the year is warranted.