Marsupial, insectivore, and chiropteran anesthesia

AN ENDOSCOPY-GUIDED TECHNIQUE FOR THE COLLECTION OF MICROBIOLOGY SAMPLES FROM THE TRACHEA OF COMMON WOMBATS (VOMBATUS URSINUS)

Respiratory infections are common in young wombats and determining the causative agent is critical to establish an appropriate treatment. A group of 12 young, wild common wombats (Vombatus ursinus) ranging from 6 to 10 kg developed a range of respiratory signs after being in care following the severe bushfires in Australia in early 2020. The oral anatomy of wombats makes collection of tracheal samples difficult. An endoscopy-guided technique was established to collect microbiology samples aseptically from the anesthetized patients. A guarded, sterile swab was introduced in the mouth and inserted into the trachea of two wombats, visualizing the procedure with the endoscope. A similar technique is described for endotracheal intubation of small mammals. This approach allowed for a safe and aseptic sampling collection. A pure growth of Escherichia coli was cultured from the samples, and appropriate antibiotic treatment was established according to the antimicrobial sensitivity test.

Evaluation of subcutaneous administration of alfaxalone-midazolam and ketamine-midazolam as sedation protocols in African pygmy hedgehogs (Atelerix albiventris)

OBJECTIVE

To evaluate SC administration of 2 sedation protocols, ketamine-midazolam (KM) and alfaxalone-midazolam (AM), in African pygmy hedgehogs (Atelerix albiventris).

ANIMALS

9 healthy adult hedgehogs (5 males, 4 females).

PROCEDURES

A randomized, blinded, complete crossover study was performed. Sedation was induced by SC administration of either ketamine (30 mg/kg [14 mg/lb]) with midazolam (1 mg/kg [0.45 mg/lb]) or alfaxalone (3 mg/kg [1.4 mg/lb]) with midazolam (1 mg/kg), including a 2-week washout period between treatments. Flumazenil (0.05 mg/kg [0.02 mg/lb], SC) was administered 45 minutes after administration of either protocol to reverse the effects of midazolam. Physiologic variables, reflexes, and behaviors were monitored. Food intake and body weight were measured before and after sedation.

RESULTS

Deep sedation characterized by complete loss of the righting reflex, decreased jaw tone, decreased pelvic limb withdrawal reflex, and preservation of the palpebral reflex was produced in 7 of 9 hedgehogs after KM administration and all 9 hedgehogs after AM administration. Mean ± SD time to loss of righting reflex was 6.4 ± 2.4 minutes after KM administration and 10 ± 4.0 minutes after AM administration. Following flumazenil administration, no significant difference was found in recovery time between sedation with KM (18.8 ± 12.7 minutes) and AM (14.4 ± 7.8 minutes). No significant differences were found in respiratory rate, oxygen saturation, or body temperature between protocols, whereas heart rate was higher for sedation with KM. Both sedation protocols resulted in a transient reduction in food intake.

CONCLUSIONS AND CLINICAL RELEVANCE

Subcutaneous administration of KM and AM provided deep sedation that might be useful to facilitate routine, noninvasive procedures in hedgehogs.

The structural design of the bat wing web and its possible role in gas exchange

The structure of the skin in the epauletted fruit bat (Epomophorus wahlbergi) wing and body trunk was studied with a view to understanding possible adaptations for gas metabolism and thermoregulation. In addition, gas exchange measurements were performed using a respirometer designed for the purpose. The body skin had an epidermis, a dermis with hair follicles and sweat glands and a fat-laden hypodermis. In contrast, the wing web skin was made up of a thin bilayered epidermis separated by a connective tissue core with collagen and elastic fibres and was devoid of hair follicles and sweat glands. The wings spanned 18-24 cm each, with about 753 cm2 of surface exposed to air. The body skin epidermis was thick (61 +/- 3 microm, SEM), the stratum corneum alone taking a third of it (21 +/- 3 microm). In contrast, the wing web skin epidermis was thinner at 9.8 +/- 0.7 microm, with a stratum corneum measuring 4.1 +/- 0.3 microm (41%). The wing capillaries in the wing web skin ran in the middle of the connective tissue core, with a resultant surface-capillary diffusion distance of 26.8 +/- 3.2 microm. The rate of oxygen consumption (VO2) of the wings alone and of the whole animal measured under light anaesthesia at ambient temperatures of 24 masculineC and 33 masculineC, averaged 6% and 10% of the total, respectively. Rate of carbon dioxide production had similar values. The membrane diffusing capacity for the wing web was estimated to be 0.019 ml O2 min(-1) mmHg(-1). We conclude that in Epomophorus wahlbergi, the wing web has structural modifications that permit a substantial contribution to the total gas exchange.

Marsupial care and husbandry

Although startlingly different in anatomy and physiology from the placental mammals common to private veterinary practice, clinical care for marsupial mammals can be approached from similar perspectives. Marsupials remain undomesticated animals with challenging needs in diet and care that must consider their native environment to be successful. As wild animals, veterinary care and clinical problems of marsupials as pets can present from sources of stress, restraint, and husbandry. Veterinary professional scan prevent many of these concerns by advising caretakers on appropriate care and feeding of these species.