DIFFUSIBLE IODINE-BASED CONTRAST-ENHANCED COMPUTED TOMOGRAPHY AS A NECROPSY AID: A CASE REPORT EVALUATING RESPIRATORY DISEASE IN MACROCEPHALON MALEO.

This study describes the novel use of diffusible iodine-based contrast-enhanced computed tomography (diceCT) as a digital necropsy aid. DiceCT was used postmortem to evaluate the cause of progressive respiratory disease in a juvenile maleo (Macrocephalon maleo). The technique facilitated soft-tissue contrast and a three-dimensional investigation of sinus and choanal anatomy as a means to identify normal and pathologic morphologies. Results showed right-sided narial occlusion by mucoid debris, along with left-sided choanal stenosis caused by osteomyelitis and reactive bone formation. The high spatial resolution afforded by diceCT enabled targeted histology and quantification of the clinical impact of pathologies, which contributed to an effective 60% loss in nasal airway aperture for this individual. This study demonstrates how adding diceCT to traditional necropsy can proffer additional understanding of an individual's pathology, and the resulting data can enhance research programs in vertebrate anatomy, evolution, and health.

PHARMACOKINETICS OF A SINGLE ORAL DOSE OF PONAZURIL IN THE INDIAN PEAFOWL (PAVO CRISTATUS).

Ponazuril, a novel coccidiocidal triazinetrione, has shown promise in addressing apicomplexan diseases in mammals and birds. This study describes the pharmacokinetics of ponazuril in healthy adult Indian peafowl (Pavo cristatus) following a single oral dose administered at two different dosages. Peafowl (four males and four females) were administered compounded ponazuril at 20 or 40 mg/kg orally in a double crossover design, with a 2-wk washout period. Blood was collected from each bird at 2, 4, 8, 24, 48, 72, 96, and 120 h after administration for plasma concentration of ponazuril using high-pressure liquid chromatography. Fecals were evaluated for coccidial shedding for 3 consecutive d prior to the ponazuril trial, 1 wk after the first dose of ponazuril, and 1 wk after the second dose of the trial. After the first trial, one peafowl administered 20 mg/kg ponazuril was shedding coccidia, but no coccidia were detected by the end of the second trial. Ponazuril reached peak concentrations (Tmax) at 21.38 h + 5.25 and 22.04 h + 7.39, and peak concentration (Cmax) were 11.82 µg/ml + 3.01 and 18.42 µg/ml + 4.13, for 20 and 40 mg/kg doses, respectively. Ponazuril was detected at 120 h with a concentration of 9.48 µg/ml + 2.59 and 12.25 µg/ml + 2.89 and a half-life of 219.4 + 58.7 h and 186.7 + 58.7 h, for and 40 mg/kg doses, respectively. Ponazuril in peafowl was well absorbed orally, plasma concentrations increased with dose, and elimination was slower than current dosages for birds would suggest. No obvious adverse effects were observed at either dosage.

Phylogeography, Population Structure, and Species Delimitation in Rockhopper Penguins (Eudyptes chrysocome and Eudyptes moseleyi).

Rockhopper penguins are delimited as 2 species, the northern rockhopper (Eudyptes moseleyi) and the southern rockhopper (Eudyptes chrysocome), with the latter comprising 2 subspecies, the western rockhopper (Eudyptes chrysocome chrysocome) and the eastern rockhopper (Eudyptes chrysocome filholi). We conducted a phylogeographic study using multilocus data from 114 individuals sampled across 12 colonies from the entire range of the northern/southern rockhopper complex to assess potential population structure, gene flow, and species limits. Bayesian and likelihood methods with nuclear and mitochondrial DNA, including model testing and heuristic approaches, support E. moseleyi and E. chrysocome as distinct species lineages with a divergence time of 0.97 Ma. However, these analyses also indicated the presence of gene flow between these species. Among southern rockhopper subspecies, we found evidence of significant gene flow and heuristic approaches to species delimitation based on the genealogical diversity index failed to delimit them as species. The best-supported population models for the southern rockhoppers were those where E. c. chrysocome and E. c. filholi were combined into a single lineage or 2 lineages with bidirectional gene flow. Additionally, we found that E. c. filholi has the highest effective population size while E. c. chrysocome showed similar effective population size to that of the endangered E. moseleyi. We suggest that the current taxonomic definitions within rockhopper penguins be upheld and that E. chrysocome populations, all found south of the subtropical front, should be treated as a single taxon with distinct management units for E. c. chrysocome and E. c. filholi.

DIAGNOSIS AND MANAGEMENT OF MYCOBACTERIOSIS IN A COLONY OF LITTLE PENGUINS (EUDYPTULA MINOR).

A group of zoo-housed little penguins (Eudyptula minor) was diagnosed with mycobacteriosis. While undergoing multidetector computed tomography (MDCT) imaging for an unrelated research project, pulmonary lesions were detected in multiple individuals. In general, birds appeared healthy and free of outward signs of disease. After the loss of three individuals, polyclonal mycobacterial disease due to Mycobacterium avium-intracellulare complex was confirmed. Surviving birds were treated with rifampin (45 mg/kg), ethambutol (30 mg/kg), clarithromycin (10 mg/kg), and enrofloxacin (30 mg/kg) compounded into a single capsule administered once a day in food. After 3 mo of therapy, MDCT imaging documented a decrease in nodule size and number in all remaining birds, with further improvement documented after 13 mo of treatment. MDCT imaging was invaluable for diagnosing disease, documenting disease progression over time, and assessing response to therapy. Early initiation of therapy before the development of outward signs of disease led to resolution of mycobacterial pulmonary lesions in multiple penguins. Mycobacterial disease in this group of little penguins, as well as previously published reports, suggests that the species is at increased risk for developing mycobacteriosis.

STANDING COMPUTED TOMOGRAPHY IN NONANESTHETIZED LITTLE PENGUINS (EUDYPTULA MINOR) TO ASSESS RESPIRATORY SYSTEM ANATOMY AND MONITOR DISEASE.

Multidetector computed tomography (MDCT) scans were performed in clinically healthy, nonanesthetized, standing little penguins (Eudyptula minor) to determine reference ranges for air-sac and lung volumes, as well as lung density. Five of 15 clinically healthy birds were diagnosed with pulmonary granulomas on initial MDCT scans. Granulomas were not readily apparent on radiographs, even in cases where the entire normal pulmonary parenchymal architecture was effaced on the MDCT scan. Serial MDCT scans after antifungal and antimycobacterial therapies demonstrated a response to treatment. MDCT scanning in nonanesthetized little penguins proved to be a well-tolerated, non-invasive imaging modality for respiratory diseases that are otherwise difficult to diagnose, including aspergillosis and mycobacteriosis.

Husbandry protocols for the Band-tailed pigeon, Patagioenas fasciata albilinea, at the WCS, Bronx Zoo for future conservation management programs.

From 2015 to 2016 we determined the husbandry protocols involved in the captive rearing of the Band-tailed Pigeon (BTPI), Patagioenas fascinate albilinea, for use as a tool in the future management of like extant and extinct avian taxa. Current and historical ex-situ conservation management of BTPIs and the closely related Passenger Pigeon, Ectopistes migratorius, is limited in scope and required further examination. Focus on the BTPI within zoos and private aviculture facilities is currently lacking. New pressures on the wild populations and future examination of the parameters involved in the possible restoration of the Passenger Pigeon may rely on a complete understanding of these conservation management techniques. Here we report on the establishment of a colony of BTPIs, at the Wildlife Conservation Society (WCS), and detail the progress attained. A confiscated group of BTPIs was presented to WCS and allowed us to set up the colony, document the husbandry involved, and monitor neonatal development and the factors that influence that development. The information has provided a better understanding of the BTPI and has implications for the future conservation management of this and like species.

Genomic Analysis of Demographic History and Ecological Niche Modeling in the Endangered Sumatran Rhinoceros Dicerorhinus sumatrensis.

The vertebrate extinction rate over the past century is approximately 22-100 times greater than background extinction rates [1], and large mammals are particularly at risk [2, 3]. Quaternary megafaunal extinctions have been attributed to climate change [4], overexploitation [5], or a combination of the two [6]. Rhinoceroses (Family: Rhinocerotidae) have a rich fossil history replete with iconic examples of climate-induced extinctions [7], but current pressures threaten to eliminate this group entirely. The Sumatran rhinoceros (Dicerorhinus sumatrensis) is among the most imperiled mammals on earth. The 2011 population was estimated at ≤216 wild individuals [8], and currently the species is extirpated, or nearly so, throughout the majority of its former range [8-12]. Understanding demographic history is important in placing current population status into a broader ecological and evolutionary context. Analysis of the Sumatran rhinoceros genome reveals extreme changes in effective population size throughout the Pleistocene. Population expansion during the early to middle Pleistocene was followed by decline. Ecological niche modeling indicated that changing climate most likely played a role in the decline of the Sumatran rhinoceros, as less suitable habitat on an emergent Sundaland corridor isolated Sumatran rhinoceros populations. By the end of the Pleistocene, the Sundaland corridor was submerged, and populations were fragmented and consequently reduced to low Holocene levels from which they would never recover. Past events denuded the Sumatran rhinoceros of genetic diversity through population decline, fragmentation, or some combination of the two and most likely made the species even more susceptible to later exploitation and habitat loss. VIDEO ABSTRACT.