Low Usutu virus seroprevalence in four zoological gardens in central Europe.

BACKGROUND: Usutu virus (USUV), a mosquito-borne flavivirus of the Japanese encephalitis virus antigenic group, caused bird die-offs in Austria, Hungary and Switzerland between 2001 and 2009. While the zoological gardens of Vienna and Zurich recorded USUV-associated mortality in different species of birds during this period, incidences in Budapest were limited to areas outside the zoo, and in the greater Basel area avian mortality due to USUV infection was not observed at all. The objectives of this investigation were to gain insight into USUV infection dynamics in captive birds in zoos with varying degrees of virus exposure and to study differences in susceptibility to USUV of different species of birds. RESULTS: 372 bird sera were collected between October 2006 and August 2007. The samples were tested in parallel by hemagglutination inhibition (HI) and 90% plaque reduction neutralization tests (PRNT-90). 8.75%, 5.3% and 6.59% of birds in the zoos of Vienna, Zurich and Basel, respectively, showed USUV-specific antibodies by PRNT-90. No antibodies to USUV were detected in birds of the Budapest zoo. The order Strigiformes (owls) exhibited the highest USUV-seroprevalence, compared to other orders of birds. CONCLUSIONS: USUV seems not to pose an imminent threat to zoo bird populations in central Europe at the moment. Depending on a variety of especially environmental factors, however, this may change at any time in the (near) future, as experienced with West Nile virus (WNV). It is therefore strongly suggested to continue with combined WNV and USUV surveillance activities in affected areas.

Total intravenous anesthesia with midazolam, ketamine, and xylazine or detomidine following induction with tiletamine, zolazepam, and xylazine in red deer (Cervus elaphus hippelaphus) undergoing surgery.

Sixteen captive female red deer were successfully anesthetized to surgically implant a telemetry system. The deer were immobilized with (mean±SD) 1.79±0.29 mg/kg xylazine and 1.79±0.29 mg/kg tiletamine/zolazepam given intramuscularly with a dart gun. Anesthesia was maintained for 69±2 min using a total intravenous protocol with a catheter placed in the jugular vein. Group X received xylazine (0.5±0.055 mg/kg/hr) and group D, detomidine (2±0.22 µg/kg/hr), both in combination with ketamine (2±0.02 mg/kg/hr) and midazolam (0.03±0.0033 mg/kg/hr), as a constant rate infusion. Anesthesia was reversed with 0.09±0.01 mg/kg atipamezole and 8.7±1.21 µg/kg sarmazenil given intravenously in both groups. These drug combinations provided smooth induction, stable anesthesia for surgery, and rapid recovery. Respiratory depression and mild hypoxemia were seen, and we, therefore, recommend using supplemental intranasal oxygen.

Microscopic morphology of the elephant's hoof.

As a result of the lack of basic microscopic anatomy of the elephants' foot, this study deals with the normal microscopic morphology of both the Asian (Elephas maximus) and African (Loxodonta africana) elephant foot with consideration of pathologic changes. A total of 727 histologic samples from defined locations of 24 hooves of both species (17 Asian and seven African species) were studied, measured, and evaluated. Minor differences between the feet and species are seen histologically. Poor horn quality in captive elephants' hooves and loci of minor resistance in captive and wild animals are detected. The thickness of the weight-bearing surface of the captive elephants' hooves is histologically measured as "very thin" (about 10 mm). The normal histologic findings provide a basis for assessing histopathologic changes and especially horn quality. The histologic findings might explain some of the foot problems, but they also give rise to questions about the quality and correctness of current husbandry techniques.

Evaluation of three combinations of anesthetics for use in free-ranging alpine marmots (Marmota marmota).

From April 1998 to September 2000, 241 free-ranging alpine marmots (Marmota marmota) were anesthetized in the course of a field project using either xylazine plus ketamine (XK), medetomidine plus ketamine (MK), or xylazine plus a 1:1 mixture of zolazepam and tiletamine (XZT). For each of the combinations, the respective doses for short term and long-term surgery were established and seasonal variations in the amount of drugs needed were assessed. No fatalities occurred, and doses for efficient and safe anesthesia in spring were as follows (XK, MK, and XZT, respectively, in mg/kg body mass): short term surgery 3 + 40, 0.25 + 35, and 3 + 15; long term surgery 20 + 80, 0.5 + 70, and 10 + 20. In late summer/autumn, higher doses (20 + 60, 0.2 + 60, and 10 + 15 for short term surgery) had to be administered, probably due to increase of marmots' body fat content. Heart rate, respiratory rate, rectal temperature, palpebral reflex, muscle relaxation, and analgesia were monitored to evaluate the animals' responses to each of the drug combinations. Hypothermia was induced by all combinations and heart rate significantly decreased during anesthesia, especially in marmots receiving MK. Respiratory rate was highly variable and no significant differences between the drugs were found. Muscle relaxation was rather poor in marmots anesthetized with XK. The XZT combination tended to have a longer induction period but was found to subsequently depress the palpebral reflex and induce muscle relaxation and analgesia very efficiently. We conclude that, regardless of the anesthetics used, doses should always be adjusted to the planned manipulations, the marmots' nutritional state, and to the time of year. Furthermore, close monitoring of physiologic parameters, especially body temperature, should be guaranteed. On the basis of physiologic and behavioral responses, XZT is the most effective drug combination for anesthetizing alpine marmots, especially for long term, potentially painful procedures.