EVALUATION OF A PARTIALLY REVERSIBLE IMMOBILIZATION PROTOCOL USING MEDETOMIDINE, BUTORPHANOL, ZOLAZEPAM-TILETAMINE, AND KETAMINE IN FREE-RANGING WARTHOGS (PHACOCHOERUS AFRICANUS) IN KRUGER NATIONAL PARK, SOUTH AFRICA.

Twenty-one free-ranging warthogs (Phacochoerus africanus) in the Kruger National Park, South Africa, were immobilized with a combination of medetomidine (0.07 ± 0.01 mg/kg), butorphanol (0.26 ± 0.04 mg/kg), tiletamine-zolazepam (0.69 ± 0.15 mg/kg), and ketamine (1.43 ± 0.21 mg/kg) administered intramuscularly by dart. Induction, immobilization, and recovery characteristics were evaluated using a standardized scoring system. In the immobilized warthogs, physiological variables were measured every 5 min and arterial blood gases were analyzed at 15-min intervals. At 45 min after initial drug administration, atipamezole (0.34 ± 0.050 mg/kg) and naltrexone (0.53 ± 0.079 mg/kg) were administered intravenously. Overall, induction quality after darting was scored as excellent and the mean time to safe handling was 5.9 ± 2.0 min. Based on muscle relaxation, and loss of palpebral and pedal reflexes, most subjects (17 out of 21) reached a plane of surgical anesthesia by 10 and 15 min; 20 out of 21 warthogs were in this plane for the duration of the monitoring period. In the immobilized warthogs the overall mean heart rate was 65 ± 15.3 beats per minute, mean respiratory rate was 14.7 ± 5.6 breaths per minute, and the mean rectal temperature was 37.9 ± 1.4°C during the 40 min. Arterial blood gas results showed hypoxemia (mean PaO2 62.1 ± 16.2 mmHg), hypercapnia (mean PaCO2 47.1 ± 5.1 mmHg), and acidemia (mean pH = 7.36 ± 0.04). Values for PaO2 and pH improved over the immobilization period. After antagonist administration, overall recovery quality from immobilization was scored as good, with animals standing at a mean time of 7.3 ± 4.9 min. The drug combination proved to be effective in the immobilization of free-ranging warthogs with rapid induction, good anesthesia, and limited cardiorespiratory changes. This anesthetic protocol produces effective, safe, and partially reversible immobilization in warthogs.

MYCOBACTERIUM BOVIS IN FREE-RANGING LIONS (PANTHERA LEO) - EVALUATION OF SEROLOGICAL AND TUBERCULIN SKIN TESTS FOR DETECTION OF INFECTION AND DISEASE.

Bovine tuberculosis (bTB), caused by Mycobacterium bovis infection, causes morbidity and mortality in free-ranging lions in bTB-endemic areas of South Africa. However, the only currently used diagnostic test is the tuberculin skin test (TST). This test is logistically challenging to perform because it requires immobilization of lions twice in a 72-hr period. Blood-based diagnostic tests, such as serological assays, have been previously reported for M. bovis detection in lion populations, and have the advantage of only requiring a single immobilization. In addition, serological assays can be used for retrospective testing. Therefore, the aim of this study was to test free-ranging lions with the STAT-PAKt (Chembio Diagnostics Systems, Medford, NY 11763, USA) and DPPt VetTB (Chembio Diagnostics Systems) serological assays and compare those results with the tuberculin skin test. The serological assays were also used to determine prevalence in bTB-endemic and uninfected lion populations. The results showed that the serological assays could distinguish between M. bovis culture-positive and -negative lions. In addition, antigen-specific humoral responses were present in lions that had clinical signs of bTB disease or were shedding M. bovis antemortem. Although the seroprevalence of M. bovis infection in Kruger National Park lions was similar to that obtained from antemortem mycobacterial culture (4.8 and 3.3%, respectively), it was less than that estimated by the TST (72%). These findings support the hypothesis that assays based on cell-mediated immune responses are more sensitive than serology is in detecting M. bovis infection in lions. However, serological assays can have a role in bTB disease detection in lions and are especially useful for retrospective studies.

CLINICAL CONDITIONS FOUND RADIOGRAPHICALLY IN THE FRONT FEET OF RETICULATED GIRAFFE (GIRAFFA CAMELOPARDALIS RETICULATA) IN A SINGLE ZOO.

Front foot radiographs from 22 giraffe (Giraffa camelopardalis reticulata) at one zoo were analyzed to better understand causes of lameness in this giraffe population. The herd had a history of front hoof overgrowth and intermittent lameness. Radiographic findings included distal interphalangeal joint osteoarthritis (OA), distal phalangeal bone (P3) osteitis, P3 fractures, P3 rotation, and sesamoid bone cysts. OA of the distal interphalangeal joint occurred in at least one front foot of 73% (16/22 giraffe) of the herd, and all giraffe had OA by 7 yr of age. Pedal osteitis was present in at least one front foot in 86% (19/22) of the giraffe, starting in animals as young as 1 yr old. P3 fractures were present in 36% (8/22) of the herd. These fractures were near the site of the deep digital flexor attachment and were diagnosed in giraffe as young as 10 yr old. The presence of severe osteitis was associated with the presence of P3 fractures. This study is unique in that a large herd was trained to participate in voluntary front foot radiographs so multiple causes of foot disease could be diagnosed antemortem and without anesthesia. Although the underlying causes of these lesions are likely multifactorial and currently unknown to us, the high prevalence of foot disease in relatively young animals warrants further investigation across zoos. In this study, OA, osteitis, and P3 fractures were common radiographic findings among giraffe that were limping. Subsequent monitoring and management changes suggest that proactive management of foot health can decrease morbidity and mortality in zoo giraffe.

Postinduction butorphanol administration alters oxygen consumption to improve blood gases in etorphine-immobilized white rhinoceros.

OBJECTIVE: To investigate the effects of postinduction butorphanol administration in etorphine-immobilized white rhinoceros on respiration and blood gases. STUDY DESIGN: Randomized crossover study. ANIMALS: A group of six sub-adult male white rhinoceros. METHODS: Etorphine, or etorphine followed by butorphanol 12 minutes after recumbency, was administered intramuscularly [2.5 mg etorphine, 25 mg butorphanol (1000-1250 kg), or 3.0 mg etorphine, 30 mg butorphanol (1250-1500 kg)]. Sampling started at 10 minutes after initial recumbency, and was repeated at 5 minute intervals for 25 minutes. Arterial blood gases, limb muscle tremors, expired minute ventilation and respiratory frequency were measured at each sampling point. Calculated values included alveolar-arterial oxygen gradient [ [Formula: see text] ], expected respiratory minute volume (V˙e), tidal volume (Vt), oxygen consumption ( [Formula: see text] ) and carbon dioxide production ( [Formula: see text] ). RESULTS: Etorphine administration resulted in an initial median (range) hypoxaemia [arterial partial pressure of oxygen 25.0 (23.0-28.0) mmHg], hypercapnia [arterial partial pressure of carbon dioxide 76.2 (67.2-81.2) mmHg], increased [Formula: see text] [41.7 (36.6-45.1) mmHg, [Formula: see text] [11.1 (10.0-12.0) L minute-1] and muscle tremors. Butorphanol administration was followed by rapid, although moderate, improvements in arterial partial pressure of oxygen [48.5 (42.0-51.0) mmHg] and arterial partial pressure of carbon dioxide [62.8 (57.9-75.2) mmHg]. In rhinoceros administered butorphanol, [Formula: see text] [4.4 (3.6-5.1) L minute-1] and [Formula: see text] [4.2 (3.8-4.4) L minute-1] were lower than in those not administered butorphanol. Increased arterial oxygen tension was associated with lower oxygen consumption (p=0.002) which was positively associated with lower muscle tremor scores (p<0.0001). CONCLUSIONS AND CLINICAL RELEVANCE: Hypoxaemia and hypercapnia in etorphine-immobilized rhinoceros resulted from an increased [ [Formula: see text] ] and increased [Formula: see text] and [Formula: see text] associated with muscle tremors. Rather than being associated with changes in V˙e, it appears that improved blood gases following butorphanol administration were a consequence of decreased [Formula: see text] associated with reduced muscle tremoring.