Journal of Zoo and Wildlife Medicine最新文献

Multiple species of elephant endotheliotropic herpesvirus (EEHV) have caused fatal hemorrhagic disease in African (Loxodonta africana) and Asian (Elephas maximus) elephants. To date, EEHV7 has been detected only in benign pulmonary and skin nodules and in saliva of African elephants and has not been associated with clinical illness. Low-level viremia due to EEHV7A was detected via qPCR in two subadult African elephants during routine surveillance. Hematologic changes were noted in both elephants, including leukopenia, lymphopenia, monocytopenia, and band heterophilia. Treatment was initiated with famciclovir, antimicrobials, and rectal fluids, and one elephant received plasma transfusions due to a progressive decrease in platelet count. Both elephants remained asymptomatic throughout the viremias, with rapid resolution of hematologic abnormalities. These cases add to the current understanding of the epidemiology of EEHV in African elephants; to the authors' knowledge, they represent the first documentation of clinical disease due to EEHV7 infection in any elephant.

Growing resistance to current antiparasitic medications, both in livestock and in zoological species under human care, makes it imperative to evaluate available drugs on the market, such as eprinomectin. In this prospective study, five males and one female of reticulated (Giraffa reticulata; n = 2), Masai (Giraffa tippelskirchii; n = 1), Nubian (Giraffa camelopardalis; n = 2), and hybrid subspecies (n = 1) of giraffe, received 1.5 mg/kg eprinomectin topically along the dorsum. Using high-performance liquid chromatography, concentrations of eprinomectin in plasma samples collected at 0, 4, 24, and 48 h, and 7, 14, 21, and 28 d were evaluated following drug administration. Complete blood cell counts and biochemistry panels were performed before (n = 6) and after (n = 3) eprinomectin administration. Samples for modified double centrifugal fecal flotation (n = 6) were evaluated prior to eprinomectin administration to evaluate for endoparasites and were repeated after the study (n = 5). Noncompartmental pharmacokinetic analysis was applied to the data. The observed maximum plasma concentration was 11.45 ng/ml and the time of observed maximum concentration was 2.67 d. The mean terminal half-life was 5.16 d. No adverse effects were observed related to eprinomectin administration and no blood work changes were observed. Parasite loads decreased (n = 3) or did not change (n = 2) after eprinomectin administration. The mean peak plasma concentration of eprinomectin in giraffe was similar to that achieved in cattle, despite using three times the dose.

Four green iguanas (Iguana iguana) and one blue iguana (Cyclura lewisi) from five facilities were diagnosed with sodium urate cholelithiasis. One case was diagnosed antemortem via ultrasonography, and the iguana underwent a choledochotomy for treatment. The other four cases were identified at necropsy. Pathologic hepatic and biliary changes were present in four of the five cases at necropsy. Histologically, four iguanas had hepatic fibrosis, three had bile duct hyperplasia, and one had cholangiohepatitis and pancreaticocholedochitis. Two iguanas had pathologic renal changes. This is the first report of sodium urate cholelithiasis in reptiles. This case series highlights the potential significant clinical disease caused by sodium urate cholelithiasis and the importance of biliary system evaluation. Further investigation is recommended to explore the pathogenesis of reptilian sodium urate cholelith formation.

The Houston toad (Anaxyrus houstonensis), a primarily terrestrial amphibian of south-central Texas, has been listed as federally endangered since 1970. Sedation is an important tool for obtaining diagnostics and providing treatment in this species. This prospective, randomized, and blinded study compared the sedative effects of SC alfaxalone (Protocol A) at approximately 12 mg/kg (median [range] = 12.70 [12.09-13.95] mg/kg] to SC alfaxalone-dexmedetomidine (Protocol AD) at approximately 12 mg/kg (median [range] = 12.68 [12.16-13.56] mg/kg) and 0.1 mg/kg (median [range] = 0.1 [0.07-0.13] mg/kg), respectively, in adult Houston toads (n = 26). Toads from Protocol AD received atipamezole SC at approximately 1 mg/kg (median [range] = 0.96 [0.75-1.25] mg/kg) 45 min postinduction, whereas toads from Protocol A received the equivalent volume of SC sterile saline at the same time point. Heart rate, gular rate, and times to first effect, loss of righting reflex, ability to position for radiographs, loss of nociception, return of righting reflex, and full recovery were recorded. A significantly greater number of toads lost righting reflex, positioned for radiographs, and lost nociception with Protocol AD compared with Protocol A. Additionally, time to return of righting reflex and time to full recovery were significantly longer with Protocol AD than with Protocol A. The protocols did not differ significantly in time to first effect, time to radiographic positioning, or time to loss of nociception. Histologic examination of four toads euthanized during the study revealed acute injection site reactions from all administered drugs, including saline. No clinical adverse reactions were observed. This study demonstrates that the combination of SC alfaxalone and dexmedetomidine results in deeper sedation than SC alfaxalone alone, but also correlates with longer recovery times despite antagonist administration.

This case series investigates a cluster of deaths in a captive colony of Leschenault's rousettes (Rousettus leschenaultii). Six of seven bats that died between March and September 2021 were diagnosed postmortem with both iron overload (IO) and neoplasia, neither of which have previously been reported in this species. Iron status was assessed via hepatic histopathological grading, hepatic iron concentration, and, in two cases, serum iron concentration. On histopathological grading, all cases had hemochromatosis except one, which had hemosiderosis. Hepatic iron concentrations did not correlate with histopathological grading. Neoplasms in these six bats included hepatocellular carcinoma (HCC; 4), bronchioloalveolar adenocarcinoma (1), pancreatic adenocarcinoma (1), and sarcoma of the spleen and stomach (1). One bat had two neoplasms (HCC and sarcoma of the spleen and stomach). One additional case of HCC in 2018 was identified on retrospective case review. Etiology was investigated to the extent possible in a clinical setting. Nutritional analysis and drinking water testing found oral iron intake within acceptable bounds; however, dietary vitamin C was potentially excessive and may have contributed to IO. Panhepadnavirus PCR testing of liver tissue was negative for all bats. A species-associated susceptibility to IO, as seen in Egyptian fruit bats (Rousettus aegyptiacus), is possible. The high incidence of HCC is suspected to be related to IO; other differentials include viral infection. Causes or contributing factors were not definitively identified for the other neoplasms seen but could include age, inherited risk (given a high level of inbreeding), or an oncogenic virus. Pending further research in this species, it is recommended that keepers of Leschenault's rousettes offer conservative amounts of vitamin C and iron (as for Egyptian fruit bats), submit for postmortem examination any euthanized or found dead, and share records of similar cases.

Insects are increasingly common in households, zoological collections, research, and food industries. Increased knowledge of insect health parameters is necessary to ensure proper welfare. The study goal was to develop a hemolymph collection technique and report hemolymph serum biochemical parameters for the thorny devil stick insect (Eurycantha calcarata). Clinically healthy adult stick insects (5 males and 14 females, 15.1-24.7 g) were enrolled. Four collection techniques were evaluated. Hemolymph collection was unsuccessful in males, but was successful in females by using a single technique. The insect was manually restrained in an elevated position and an 18-ga × 2.54-cm needle was used to puncture the membrane just caudal to the third pair of legs. With the puncture site directed ventrally, ≤1 ml of hemolymph was collected via gravity and allowed to visibly clot. The sample was then centrifuged, and the serum was separated. Serum samples were individually analyzed (Avian/Reptilian Profile Plus, VetScan VS2, Abaxis, Inc, Union City, CA 94587, USA). Fourteen samples (0.2-1.0 ml) were collected from 14 females. Median (minimum-maximum) parameters included the following: aspartate aminotransferase 12 (0-45) U/L, creatinine kinase 25 (0-76) U/L, uric acid 7.5 (3.1-13.7) mg/dl, glucose 12 (8-22) mg/dl, calcium 18.6 (17.2-19.4) mg/dl, phosphorus 15.0 (n = 1) or >30.0 (n = 13) mg/dL, total protein 2.7 (1.6-2.9) g/dL, albumin 0.9 (0.2-1.2) g/dL, globulin 1.7 (1.6-1.8) g/dL (n = 6) or not quantified (n = 8), potassium 10.6 (9.0-11.8) mmol/L, sodium < 100 mmol/L, and bile acids 0 lmol/L. This is the first report of biochemistry parameters in clinically healthy female stick insects. Larger sample sizes are needed to establish statistically valid reference ranges. Hemolymph collection techniques for male stick insects warrant further investigation.

Heart disease in birds contributes to premature death and is usually detected postmortem. Echocardiography is a sensitive and noninvasive diagnostic modality but reported standard values for many species of birds, including American flamingos (Phoenicopterus ruber), are unavailable. Echocardiography was opportunistically performed on 30 unsedated American flamingos during their annual routine health examination. Structural heart disease was not found in any of the examined birds. However, 18 birds showed varying degrees of dynamic intraventricular obstruction. Echocardiographic parameters are reported. Benign neurocardiogenic weakness or syncopal events during handling were suspected in three birds. Stress combined with an intraventricular obstruction is believed to have triggered a cascade of parasympathetic innervation and sympathetic inhibition, similar to neurally mediated reflex syncope in humans.

Sedation, recovery response, and physiologic outcomes were evaluated in five captive reindeer (Rangifer tarandus) in Minnesota using a completely reversible immobilization protocol. Reindeer were immobilized with butorphanol (0.23-0.32 mg/kg), midazolam (0.23-0.32 mg/kg), and medetomidine (0.15 mg/kg) (BMM) via IM dart. Induction time (IT), recumbency time (DT), and recovery time (RT) were recorded. Temperature (T), respiratory rate (RR), pulse rate (PR), pulse oximetry (SpO₂), arterial blood gas values including oxygen (PaO₂), and carbon dioxide (PaCO₂) tensions and lactate (Lac) were recorded preoxygen supplementation and 15 min postoxygen supplementation. Reversal was done using naltrexone (2.3-3.0 mg/kg), flumazenil (0.008-0.01 mg/kg) and atipamezole (0.62-0.78 mg/kg) (NFA) IM, limiting recumbency to 1 h. Median IT, DT, and RT were 5 min, 46 min, and 7 min, respectively. SpO₂ (92 to 99%, P = 0.125), PaO₂ (45.5 to 97 mmHg, P = 0.25), and PaCO₂ (46.5 to 54.6 mmHg, P = 0.25) all increased, whereas Lac (3.02 to 1.93 mmol/L, P = 0.25) decreased between baseline and 15 min postoxygen supplementation, without statistical significance. BMM immobilization, and reversal with NFA provided rapid and effective immobilization and recovery, respectively. Oxygen supplementation mitigated hypoxemia in all reindeer.

The Rhynonyssid mesostigmatic mite, Sternostoma tracheacolum, is a well-documented endoparasitic hematophagous arthropod of the respiratory tracts of multiple avian species, particularly Estrildid finches and canaries. In this retrospective study, 175 medical and 278 pathology records for the Gouldian finch (Chloebia gouldiae) population (N = 377) at the San Diego Zoo between 2013 and 2021 were analyzed to evaluate the effectiveness of ivermectin-based prophylaxis. A multivariable negative binomial regression model was constructed to evaluate the population effects of monthly treatments on morbidity or mortality associated with respiratory mites. While controlling for other factors in the model, the prophylactic treatment did not significantly reduce the monthly rate of mite-associated morbidity or mortality (IRR = 1.017, 95% CI: 0.997-1.036, P = 0.0759); however, low proportions of the population were prophylactically treated over time. Different factors were significant when separately evaluating adjusted associations with respiratory morbidity and mortality. The findings suggest increased rates of respiratory morbidity for each successive year of the study period (IRR = 1.180, 95% CI: 1.046-1.342, P = 0.0090) and increased rates of mite-associated mortality occurring annually between May and October (IRR = 1.697, 95% CI: 1.034-2.855, P = 0.0404) compared to the wet winter season. Our findings highlight the need to continually evaluate and optimize treatment regimens in zoological collections. Further investigations into this host-parasite relationship and potential treatments and preventive therapies are warranted.

The maned sloth (Bradypus torquatus) is an endemic and endangered species of two Brazilian states, with much unknown biological information needed to direct conservation actions. Other sloth species have been studied regarding anesthesia; however, there is a lack of anesthesia research for the maned sloth. Anesthetic data were collected from 12 free-range maned sloths that were immobilized for a field examination. Individuals were anesthetized using a combination of ketamine (4.0 mg/kg) and medetomidine (0.03 mg/kg), and antagonized with atipamezole (0.1 mg/kg). Time to induction and recovery were recorded and compared with sex and age classes. After the induction and until antagonist administration, physiological parameters (rectal temperature, heart rate, respiratory rate, and oxygen saturation) were recorded every 10 min during anesthesia and were statistically evaluated over time. Induction was fast (3.21 ± 0.76), but recovery was longer (113.3 ± 18) when compared to other studies. Induction and recovery times were not different across sex or age classes. Rectal temperature, heart rate, and oxygen saturation remained stable throughout the procedure. Respiratory rate significantly decreased over time, from 18.25 ± 7.03 to 13.17 ± 3.66 movements per minute. Our results indicate that the described combination of ketamine and medetomidine is a safe and effective choice for anesthesia of maned sloths.