Larry Vogelnest

Afternoon shedding of a new species of Isospora (Apicomplexa) in the endangered Regent Honeyeater (Xanthomyza phrygia).

The Regent Honeyeater (Xanthomyza phyrigia) is an endangered Australian bird species. Breeding populations have been established at Australian zoos in support of re-introduction programmes. This species is the host of a new species of Isospora (Apicomplexa). Oocysts are spherical, 25·8 (22·5-28·75) by 23·8 (20-26·25) μm with a colourless to pale yellow smooth wall undergoing rapid exogenous sporulation, 90% sporulated oocysts in 8 h at 20°C. Each oocyst contains 1 polar granule. Sporocysts are ovoid, 18·67 (17-19) by 9·49 (9-10) μm with a flat Stieda body and spherical substieda body devoid of a hyaline body. The asexual stages and sexual phase is within the enterocytes of the duodenum and jejunum. Faeces collected in the morning (AM, n=84) and in the afternoon (PM, n=90) revealed significant diurnal periodicity in oocyst shedding; 21% (18 of 84) of the AM were positive with the mean of 499 oocysts.g-1 compared to the PM with 91% (82 of 90) bird faeces positive with the mean of 129 723 oocysts.g-1. Therefore, parasite checks for these birds should be carried out in the afternoon to obtain an accurate result. The ecological significance of the high parasite burden in captive birds requires further investigation and comparison to the wild counterparts.

COMPARISON OF ETORPHINE–DETOMIDINE AND MEDETOMIDINE–KETAMINE ANESTHESIA IN CAPTIVE ADDAX (ADDAX NASOMACULATUS)

Abstract Thirty-five anesthetic events involving 15 captive addax (Addax nasomaculatus) were performed between August 1998 and February 2002 using a combination of etorphine (33.7 ± 7.9 μg/kg) and detomidine (21.9 ± 4.6 μg/kg) or a combination of medetomidine (57.4 ± 8.6 μg/kg) and ketamine (1.22 ± 0.3 μg/kg), with or without supplemental injectable or inhalant anesthetic agents. Etorphine–detomidine anesthesia was antagonized with diprenorphine (107.1 ± 16.4 μg/kg) and atipamezole (100.9 ± 42.4 μg/kg). Medetomidine–ketamine anesthesia was antagonized with atipamezole (245.3 ± 63.4 μg/kg). Animals became recumbent within 5 min when the combination of etorphine and detomidine was used and within 11 min when the combination of medetomidine and ketamine was used. Both drug combinations were suitable for use as primary immobilizing agents producing short-duration restraint and analgesia. Bradycardia was noted with both combinations. Further investigation of the cardiopulmonary effects of both combinations is warranted.

A retrospective study of Babesia macropus associated with morbidity and mortality in eastern grey kangaroos (Macropus giganteus) and agile wallabies (Macropus agilis)

Highlights • Detailed description of novel Babesia infection causing mortality in macropods.• First report of this infection in agile wallabies.• Information on the geographical incidence of this disease in the eastern states of Australia.• Comprehensive review of the clinical signs and pathology of the disease.

AN UNDESCRIBED DEMODEX SP. AND DEMODICOSIS IN A CAPTIVE KOALA (PHASCOLARCTOS CINEREUS)

Abstract A 12-yr-old male koala (Phascolarctos cinereus) in a zoo collection developed bilateral, noninflammatory, periocular alopecia. Deep periocular skin scrapings yielded multiple adult, nymphal, and larval mites of a previously undescribed Demodex species. Skin biopsies from affected areas revealed multiple mites in superficial keratin and within hair follicles, associated with a mild intramural lymphocytic folliculitis. Treatment with daily oral ivermectin was safe and effective. Although Demodex sp. are previously reported from skin scrapings in another koala with periocular alopecia, this is the first confirmed case of koala demodicosis.

Diagnosis and management of tuberculosis (Mycobacterium tuberculosis) in an Asian elephant (Elephas maximus) with a newborn calf.

Abstract:  In 2006, five Asian elephants (Elephas maximus) were imported to Taronga Zoo, Australia, from Thailand. Pre-import and initial postarrival tuberculosis screening was performed by trunk wash (TW) culture and was negative for Mycobacterium tuberculosis. In April 2009, the ElephantTB STAT-PAK® (SP) assay was used to test the elephants. A 15.5-yr-old pregnant cow was reactive. TW frequency for this cow was increased from annually to quarterly. TW cultures remained negative on all other elephants. In February 2010, the Dual Path Platform® (DPP) VetTB assay was used for the first time, and the SP-reactive cow also reacted on the DPP. A SP was run concurrently and was reactive. All other elephants were nonreactive on both assays. Treatment was not initiated due to concern about the effect of antituberculous drugs on the fetus. Quarterly TW cultures continued. The cow gave birth on 2 November 2010. A routine TW on 24 November 2010 was culture positive for M. tuberculosis. Although previous shedding could not be ruled out, reactivation of latent infection or exacerbation of subclinical disease due to parturition was suspected. Treatment with isoniazid, pyrazinamide, rifampicin, and ethambutol commenced. A 12-mo treatment course was completed within a 15-mo period. The isolate was susceptible to these drugs and genotyped as a Beijing strain. Stored serum samples from 2004 and 2006 were tested retrospectively and were reactive on SP and DPP. TW, SP, and DPP screening frequency increased to monthly for the positive cow on commencement of treatment in January 2011. Monthly serum biochemistry indicated drug-induced hepatitis. Therapeutic drug monitoring was conducted to ensure therapeutic levels were achieved. The infant calf was reactive on DPP, but TW culture negative, and was not treated. Serial DPP results for the cow and calf during and after treatment indicated that the antibody levels were declining, suggesting a favorable response to therapy in the dam, and that the origin of the antibodies in the calf were maternal, rather than a response to infection.

Year-Long Presence of Eimeria echidnae and Absence of Eimeria tachyglossi In Captive Short-Beaked Echidnas (Tachyglossus aculeatus)

Abstract: The short-beaked echidna (Tachyglossus aculeatus) is 1 of 5 extant species of monotreme, found only in Australia and Papua New Guinea. The aim of this study was to identify the species of coccidia present and establish a range of subclinical Eimeria spp. (Coccidia: Apicomplexa) oocyst shedding in echidnas from eastern Australia over 18 mo. The coccidia were detected in 89% (49/55) of fecal samples from 12 long-term monitored and healthy captive echidnas, 75% (3/4) of 4 healthy long-term captive echidnas, 83% (5/6) of 6 short-term captive echidnas, and 60% (6/10) of 10 wild echidnas. Echidnas captive for 4 to 23 yr shed 100–46,000 oocysts g−1 of E. echidnae and remained clinically healthy during this study. Sub-adult and adult wild, and short-term captive, echidnas shed oocysts of both E. echidnae and E. tachyglossi. The lack of coccidia in juvenile short-beaked echidnas suggests these animals are probably non-immune and should not be placed in environments heavily contaminated with oocysts. In addition, no oocysts were found in captive long-beaked echidnas (Zaglossus bartoni bartoni, n  =  2) housed at Taronga Zoo. This study represents an important step in understanding the host–parasite interaction between coccidia and short-beaked echidnas.

ACUTE LYMPHOBLASTIC LEUKEMIA IN A PYGMY HIPPOPOTAMUS (HEXAPROTODON LIBERIENSIS)

Abstract:  A captive, 31-yr-old, intact male pygmy hippopotamus presented with nonspecific signs of weight loss, inappetence, diarrhea, and lethargy. After 5 wk of diagnostic investigation and symptomatic treatment, an acute leukemic process with concurrent polycystic kidney disease was suspected. The animals condition continued to deteriorate prompting euthanasia. Necropsy, histopathologic, and immunohistochemical examination confirmed acute T-cell lymphoblastic leukemia and polycystic kidneys. Acute T-cell lymphoblastic leukemia has not previously been documented in this species; however, polycystic kidney disease has been reported. This case report adds to the increasing number of pygmy hippopotamuses diagnosed with polycystic kidney disease and describes acute T-cell lymphoblastic leukemia, a previously unreported disease of this species.

Intercontinental distribution of a new trypanosome species from Australian endemic Regent Honeyeater ( Anthochaera phrygia )

Establishing a health screening protocol is fundamental for successful captive breeding and release of wildlife. The aim of this study was to undertake a parasitological survey focusing on the presence of trypanosomes in a cohort of Regent Honeyeaters, Anthochaera phrygia, syn. Xanthomyza phrygia (Aves: Passeriformes) that are part of the breeding and reintroduction programme carried out in Australia. We describe a new blood parasite, Trypanosoma thomasbancrofti sp. n. (Kinetoplastida: Trypanosomatidae) with prevalence of 24·4% (20/81) in a captive population in 2015. The sequence of the small subunit rRNA gene (SSU rDNA) and kinetoplast ultrastructure of T. thomasbancrofti sp. n. are the key differentiating characteristics from other Trypanosoma spp. T. thomasbancrofti sp. n. is distinct from Trypanosoma cf. avium found in sympatric Noisy Miners (Manorina melanocephala). The SSU rDNA comparison suggests an intercontinental distribution of T. thomasbancrofti sp. n. and Culex mosquitoes as a suspected vector. Currently, no information exists on the effect of T. thomasbancrofti sp. n. on its hosts; however, all trypanosome-positive birds remain clinically healthy. This information is useful in establishing baseline health data and screening protocols, particularly prior to release to the wild.

Dilated cardiomyopathy in a De Brazza's monkey (Cercopithecus neglectus)

Cardiomyopathies have been reported in many primates. They may result from an inflammatory response to an infectious agent, nutritional deficiency, familial‐genetic inheritance or toxic agents, but in many cases they are idiopathic.

Tuberculosis: an emerging zoonosis

Tuberculosis (TB) caused by Mycobacterium tuberculosis is primarily a disease of humans who are considered the primary reservoir host for this pathogen. It is an ancient disease, with descriptions dating back thousands of years. It is currently estimated that one-third of the global human population is infected, 1 and TB accounts for millions of