Ketamine-medetomidine compared to tiletamine-zolazepam-medetomidine for immobilisation of semi-captive cheetahs (Acinonyx jubatus).

ABSTRACT: The immobilisation time and cardiopulmonary effects of ketamine-medetomidine (KM) and tiletamine-zolazepam-medetomidine (TZM) were compared in semi-captive cheetahs (Acinonyx jubatus). Seven healthy adult cheetahs were included in a randomised prospective crossover study. Each cheetah was immobilised on two occasions by remote injection, once with a combination of ketamine (4.93 ± 0.75 mg/kg) and medetomidine (0.038 ± 0.003 mg/kg) (KM) and once with tiletamine-zolazepam (1.16 ± 0.12 mg/kg) and medetomidine (0.039 ± 0.002 mg/kg) (TZM). Time to safe approach, characterised by absent responses to an ear flick and tail tug, was recorded as the immobilisation time. Following immobilisation, cardiopulmonary parameters were recorded, and an arterial blood gas sample analysed. Data is reported as mean ± SD and compared using a general linear mixed model (p < 0.05). Immobilisation times were no different between combinations, 11.4 ± 5.7 minutes for KM and 13.2 ± 4.6 minutes for TZM (p = 0.528). Systolic blood pressure was 218 ± 22 mmHg for KM and 210 ± 28 mmHg for TZM (p = 0.594). There was moderate hypoxaemia with both combinations with arterial oxygen partial pressure of 58.4 ± 6.6 mmHg for KM and 61.3 ± 4.2 mmHg for TZM (p = 0.368). Haematocrit was higher with KM (40.7 ± 2.5) than TZM (35.8 ± 2.8, p = 0.007). There were differences in electrolytes, with TZM resulting in higher serum potassium (4.3 ± 0.2 mmol/L, p < 0.001) and glucose (11.8 ± 2.9 mmol/L, p = 0.039) than KM. Both combinations provided acceptable immobilisation for field use, although severe hypertension was a consistent finding. Supplementation with oxygen is recommended with both combinations.

Development of a Gene Expression Assay for the Diagnosis of Mycobacterium bovis Infection in African Lions (Panthera leo).

Mycobacterium bovis infection, the cause of bovine tuberculosis (BTB), is endemic in wildlife in the Kruger National Park (KNP), South Africa. In lions, a high infection prevalence and BTB mortalities have been documented in the KNP; however, the ecological consequences of this disease are currently unknown. Sensitive assays for the detection of this infection in this species are therefore required. Blood from M. bovis-exposed, M. bovis-unexposed, M. tuberculosis-exposed and M. bovis-infected lions was incubated in QuantiFERON® -TB Gold (QFT) tubes containing either saline or ESAT-6/CFP-10 peptides. Using qPCR, selected reference genes were evaluated for expression stability in these samples and selected target genes were evaluated as markers of antigen-dependent immune activation. The abundance of monokine induced by gamma interferon (MIG/CXCL9) mRNA, measured in relation to that of YWHAZ, was used as a marker of ESAT-6/CFP-10 sensitization. The gene expression assay results were compared between lion groups, and lenient and stringent diagnostic cut-off values were calculated. This CXCL9 gene expression assay combines a highly specific stimulation platform with a sensitive diagnostic marker that allows for discrimination between M. bovis-infected and M. bovis-uninfected lions.

Ultrasonographic and laparoscopic evaluation of the reproductive tract in older captive female cheetahs (Acinonyx jubatus).

The study uniquely described the clinical value of transabdominal ultrasonography for monitoring features characterizing the estrous cycle in female cheetahs (Acinonyx jubatus). The reproductive tracts of 21 female, nulliparous, and relatively aged (median: 11 and interquartile range: 9.25-14 years) captive cheetahs resident on two sites in Namibia were assessed by transabdominal ultrasound. Subsequently, the ovarian findings on ultrasound were compared with direct visualization while performing laparoscopic sterilization. A combination of these observations supported by concurrent sampling for vaginal cytology and serum progesterone concentrations defined the estrous status of individual animals. At one site, six cheetahs had been implanted with the GnRH agonist, deslorelin as a contraceptive at least once within the preceding 11 years. On ultrasound, 31 uterine horns and 35 ovaries with discernible structures on 28 (86%) were visualized in the 21 cheetahs. The uterine body was difficult to visualize because of its intrapelvic location. Eleven of 19 uteri (58%) visualized showed endometrial edema suggestive of estrogenization. The uteri of four cheetahs (19%) showed evidence of mild cystic endometrial hyperplasia. Paraovarian cysts were seen on ultrasound (n = 21) and laparoscopy (n = 26) in 16 (76.2%) and 18 (85.7%) cheetahs, respectively. Ovarian volumes obtained from ultrasonographically determined dimensions predicted cyclic activity. Laparoscopy showed that 19 ovaries had discernible follicular structures. In the study population, 10 (47.6%) cheetahs were in proestrus or estrus; none in the luteal phase; and 11 (52.4%) in anestrus. Transabdominal ultrasound, in combination with serum progesterone concentrations and vaginal cytology, was used with acceptable accuracy to assess cyclic ovarian activity in captive cheetahs. A considerable proportion of this aged population showed ovarian activity and the prevalence of paraovarian cysts was notable. A history of prior deslorelin treatment was not associated with either reproductive activity or uterine pathology.