Disease Surveillance of California Ground Squirrels ( Spermophilus beecheyi ) in a Drive-through Zoo in Oregon, USA.

Rodents and other small wild mammals are often considered to be pests and vectors for disease in zoos that house small populations of valuable threatened and endangered animals. In 2005, three nonhuman primates at a drive-through zoo in Oregon, US, acquired tularemia from an unknown source. Due to an abundance of California ground squirrels ( Spermophilus beecheyi ) on zoo grounds, we instituted serosurveillance of this species from July through September 2008 to determine the prevalence of antibodies against pathogens considered to be potentially transmissible to collection animals. Serologic testing was performed for Francisella tularensis ; Leptospira interrogans serovars Canicola, Grippotyphosa, Hardjo, Icterohemorrhagiae, and Pomona; Toxoplasma gondii ; and Yersinia pestis . All squirrels were seronegative for Yersinia pestis (0%; 0/45) and Toxoplasma gondii (0%; 0/20); there was a prevalence of 2% (1/45) for Francisella tularensis antibodies and 57% (24/42) were positive for various Leptospira serovars. Although it remains unclear whether ground squirrels present a significant risk for transmission of disease to zoo animals, vaccination of high-risk zoo animals against leptospirosis warrants consideration. Beyond this, continued vigilance and persistence with various forms of pest control may reduce the likelihood of disease transmission from wildlife hosts to animals in human care.

The electrocardiogram of anesthetized captive adult emus (Dromaius novaehollandiae).

OBJECTIVE: To characterize the electrocardiogram (ECG) of anesthetized adult emus (Dromaius novaehollandiae). ANIMALS: Ten clinically healthy adult emus anesthetised for routine physical examination and an electrocardiogram, for both monitoring and investigation into any evidence of cardiac disease. METHODS: The ECGs for each emu were obtained in right lateral recumbency, using a modified electrode placement that replicated the standard bipolar leads used in small mammals. Lead II was used for waveform analysis. RESULTS: Median P wave amplitude was 0.55 mV (range: 0.2-0.92 mV) and P wave duration was 0.06 s (0.04-0.09 s). S wave amplitude measured 1.42 mV (0.92-2.12 mV), T wave amplitude 0.67 mV (0.16-0.83 mV) and QRS duration was 0.07 s (0.07-0.12 s). Ninety percent of the QRS complexes were of rS type. CONCLUSION: Our study provides electrocardiographic baseline data for anesthetized adult emus.

Thiafentanil-dexmedetomidine-telazol anesthesia in greater rheas (Rhea americana).

Ratite anesthetic events are often dangerous because these birds use their powerful legs and clawed feet as a defense, and physical restraint can result in self-trauma or injury to handlers. Although various combinations of opioids, alpha-2 adrenergic agonists, and dissociative agents have been employed in ratites, few effective chemical immobilization protocols have been documented for rheas (Rhea spp.). An intramuscular, remote-delivered combination of thiafentanil (0.30 +/- 0.08 mg/kg), dexmedetomidine (7.31 +/- 2.72 microg/kg), and tiletamine-zolazepam (5.09 +/- 2.31 mg/kg) was utilized in eight adult (four male, four female) greater rheas (Rhea americana). Smooth inductions were observed. During clinical procedures, birds were intubated and maintained on isoflurane gas, and atipamezole was administered to antagonize the dexmedetomidine. At recovery, naltrexone was administered to antagonize the thiafentanil, and midazolam was administered to smooth crate recoveries until release. This low-volume, high-potency, reversible drug combination demonstrated safe inductions and smooth recoveries and proved to be a reliable anesthetic regimen for greater rheas.

Anesthesia of Tibetan yak (Bos grunniens) using thiafentanil - xylazine and carfentanil - xylazine.

The use of 0.025 +/- 0.012 mg/kg (median +/- interquartile range) thiafentanil with 0.15 +/- 0.03 mg/kg xylazine (TX) and 0.011 +/- 0.0015 mg/kg carfentanil with 0.25 +/- 0.093 mg/kg xylazine (CX), with dosages based on estimated bodyweight, was used in the anesthesia of 37 Tibetan yak (Bos grunniens) housed within a drive-through animal park setting. The median time to lateral recumbency was 5 and 7 min for each group, respectively. With the addition of propofol in 8 CX animals and 17 TX animals, the anesthetic plane was suitable for a wide range of procedures. The median time to standing recovery following administration of naltrexone was 4 +/- 3.5 min with TX and 7 +/- 1.5 min with CX. There was one fatality and one case of renarcotization in the TX group. Overall, the dosages used in the study provided a reliable and useful anesthetic induction protocol, with TX animals demonstrating a more rapid induction and recovery with less cardiac depression than CX animals.

Use of thiafentanil-medetomidine for the induction of anesthesia in emus (Dromaius novaehollandiae) within a wild animal park.

Fifteen adult emu (Dromaius novaehollandiae) anesthetic events were successfully undertaken with the use of thiafentanil oxalate (A3080) 0.175 mg/kg i.m. (SD 0.026) and medetomidine 0.092 mg/kg i.m. (SD 0.009) via remote injection. Following induction, the birds were transported to the clinic, where a venous blood gas sample was taken for analysis, which indicated a respiratory acidosis, with a mean arterial pCO2 of 54.46 mmHg (SD 9.31) and venous pH of 7.135 (SD 0.11), most likely due to moderate bradypnoea. Atipamezole 0.2 mg/kg i.v. (SD 0.02) was administered, immediately followed by orotracheal intubation initiating 2-3% isoflurane with 2 L/min oxygen flow. Parameters evaluated during anesthesia included heart rate, respiratory rate, anesthetic depth, and electrocardiogram readings. Physical exams plus any required procedures were performed in addition to venous blood samples for biochemistry and full blood counts. The birds were then recovered in a crate padded with grass hay with administration of 8.75 mg/kg (SD 1.36) naltrexone (50 mg/mg A3080) administered in equal doses i.v. and i.m. along with 5 mg midazolam i.m. to reduce excitement. Emus were placed in a lateral position and given 4 L/min oxygen via the endotracheal tube, until movement of the head and neck necessitated extubation. Recovery was rapid and smooth in each case with a mean time of 3.1 min from antagonist administration to sternal recovery. On the basis of rapid, smooth, and successful inductions and recoveries, the described dosage of thiafentanil and medetomidine, with administration of midazolam prior to recovery, is recommended for immobilization of adult emus. Due to evidence of respiratory acidosis and bradypnoea, careful monitoring should be instituted throughout and oxygen provision recommended from initial contact.

Surveillance for selected bacterial and toxicologic contaminants in donated carcass meat fed to carnivores.

Wildlife Safari, a zoo located in Winston, Oregon, has fed donated carcass meat as a diet to carnivores for over 30 yr. Carcass meat is an alternative to commercially prepared meat. Donated meat arrives at Wildlife Safari as an entire animal. Cattle (Bos taurus), horse (Equus caballus), deer (Odocoileus hemionus), and elk (Cervus elaphus roosevelti) have been donated. Bacterial testing was performed on site with the use of Neogen Reveal immunosorbent assays. Testing focused on Salmonella spp., Listeria spp., and Escherichia coli 0157:H7. Twenty-five meat samples were randomly selected from 50 meat samples for the bacterial detection tests. Twenty-eight percent of the meat samples were positive for Salmonella spp. (n = 25). One sample was positive for Listeria spp. None of the meat samples were positive for Escherichia coli O157:H7 (n - 25). Thirty-two meat samples were analyzed off site for organic contaminants with the use of gas chromatography/mass spectrometry at Michigan State University's Diagnostic Center for Population and Animal Health. Specific organic contaminants tested for were barbiturates, phenylbutazone, flunixin meglumine, and xylazine. None of the meat samples were found to have evidence of these or any other common organic toxicants. As monitored, carcass meat appears to be a reasonably safe food source for carnivores.

Enrofloxacin-induced retinopathy in a guanaco (Lama guanicoe).

A 4-yr-old male guanaco (Lama guanicoe) in a multispecies exhibit presented with a laceration in the axillary region. The laceration was surgically repaired. Medical treatment was initiated with penicillin G procaine and benzathine (1920 IU/kg, i.m., s.i.d. for 14 days), and enrofloxacin (2.4 mg/kg, i.m., s.i.d. for 14 days). The animal was later treated with trimethoprim-sulfadiazine (24 mg/kg, p.o., s.i.d. for 10 days). Twenty-six days after initial presentation, the guanaco was suspected to be blind. An ophthalmic examination confirmed retinal damage. On postmortem histological evaluation, there was outer retinal atrophy that was most severe in the central retina with localized foci of complete retinal atrophy; lesions were similar to those observed in enrofloxacin retinal toxicity in cats.