Wayne Boardman

Parthenogenesis in Komodo dragons

Parthenogenesis, the production of offspring without fertilization by a male, is rare in vertebrate species, which usually reproduce after fusion of male and female gametes. Here we use genetic fingerprinting to identify parthenogenetic offspring produced by two female Komodo dragons (Varanus komodoensis) that had been kept at separate institutions and isolated from males; one of these females subsequently produced additional offspring sexually. This reproductive plasticity indicates that female Komodo dragons may switch between asexual and sexual reproduction, depending on the availability of a mate — a finding that has implications for the breeding of this threatened species in captivity. Most zoos keep only females, with males being moved between zoos for mating, but perhaps they should be kept together to avoid triggering parthenogenesis and thereby decreasing genetic diversity.

THE CARDIOPULMONARY EFFECTS OF ETORPHINE, AZAPERONE, DETOMIDINE, AND BUTORPHANOL IN FIELD-ANESTHETIZED WHITE RHINOCEROSES (CERATOTHERIUM SIMUM)

Abstract White rhinoceroses (Ceratotherium simum) anesthetized with etorphine combinations develop severe pathophysiologic changes, including hypoventilation, hypoxemia and metabolic acidosis. The aim of this study was to evaluate the addition of butorphanol to the immobilizing mixture on the cardiopulmonary effects in free-ranging white rhinoceroses darted from the helicopter. In the control group (n = 15), the rhinoceroses were anesthetized with etorphine, azaperone, detomidine, and hyaluronidase administered intramuscularly. In the treatment group (n = 16), 10–20 mg of butorphanol was added to the combination. Within 10 min of becoming immobile, vital parameters (heart rate, respiratory rate, and temperature) and blood gas analyses were taken, and measurements were repeated after 10 (treatment group) and 20 min (control group). Both groups showed respiratory and metabolic acidosis, hypoxemia, and hypercapnia. In the control group, the arterial partial pressure of oxygen was significantly higher and the alveolar-to-arterial oxygen pressure gradients were significantly lower in all body positions compared with the butorphanol group. Oxygen hemoglobin saturation in the control group was higher than in the butorphanol group only in the lateral position. Improvements in arterial oxygen levels were observed in all animals when placed in sternal recumbency. There were no significant differences in the mean induction times between groups, but the distance the butorphanol group ran was significantly less after darting than in the control group. By adding butorphanol to the immobilizing mixture, no benefits in ventilation were seen; although, size differences make comparisons difficult. Running for a shorter distance during induction could be beneficial in the prevention of severe acid-base imbalances and capture myopathy.

Emerging infectious diseases in free-ranging wildlife-Australian zoo based wildlife hospitals contribute to national surveillance.

Emerging infectious diseases are increasingly originating from wildlife. Many of these diseases have significant impacts on human health, domestic animal health, and biodiversity. Surveillance is the key to early detection of emerging diseases. A zoo based wildlife disease surveillance program developed in Australia incorporates disease information from free-ranging wildlife into the existing national wildlife health information system. This program uses a collaborative approach and provides a strong model for a disease surveillance program for free-ranging wildlife that enhances the national capacity for early detection of emerging diseases.

Pathological Features of Oxalate Nephrosis in a Population of Koalas (Phascolarctos cinereus) in South Australia

The wild and captive koala population of the Mt Lofty Ranges in South Australia has a high level of renal dysfunction in which crystals consistent with calcium oxalate have been observed in the kidneys. This study aimed to describe the pathological features of the renal disease in this population, confirm the composition of renal crystals as calcium oxalate, and determine whether any age or sex predispositions exist for this disease. A total of 51 koalas (28 wild rescues, 23 captive) were examined at necropsy, of which 28 (55%) were found to have gross and/or histological evidence of oxalate nephrosis. Histopathological features included intratubular and interstitial inflammation, tubule dilation, glomerular atrophy, tubule loss, and cortical fibrosis. Calcium oxalate crystals were demonstrated using a combination of polarization microscopy, alizarin red S staining, infrared spectroscopy, and energy-dispersive X-ray analysis with scanning electron microscopy. Uric acid and phosphate deposits were also shown to be present but were associated with minimal histopathological changes. No significant differences were found between the numbers of affected captive and wild rescued koalas; also, there were no sex or age predispositions identified, but it was found that oxalate nephrosis may affect koalas <2 years of age. The findings of this study suggest that oxalate nephrosis is a leading disease in this koala population. Possible causes of this disease are currently under investigation.

Capillaria hepatica (syn Calodium hepaticum) in primates in a zoological collection in the UK

Capillaria hepatica (syn Calodium hepaticum ), first described by [Bancroft (1893)][1] is a zoonotic liver nematode of mammals with a worldwide distribution. Its primary hosts are rodents, and there is a high prevalence of infection in the brown rat ( Rattus norvegicus ) ([Lloyd and others 2002][2

A molecular survey of a captive wallaby population for periodontopathogens and the co-incidence of Fusobacterium necrophorum subspecies necrophorum with periodontal diseases

Periodontal diseases (PD) are diseases of polymicrobial aetiology and constitute major health problems in captive macropods. Increasing knowledge of the causal pathogens is therefore crucial for effective management and prevention of these diseases. PCR survey and sequence analyses of potential periodontopathogens in captive wallaby populations revealed a co-incidence of the diseases with the detection of Fusobacterium necrophorum subsp. necrophorum (Fnn) and its encoded leukotoxin (lktA) gene. Sequence analyses showed that the outer membrane protein of Fnn in the GenBank database shared significant homology (99%) with the Fnn encoded haemagglutinin-related-protein gene fragment identified in this study. In addition, this report suggests the existence of a variant of Fnn with no detectable lktA gene and thus warrants further studies. In contrast to reports associating Porphyromonas gingivalis and F. nucleatum with PD, this study revealed that PD in macropods are associated with Porphyromonas gulae and Fnn and raises the question: is there a possible host pathogen co-evolution in the pathogenesis of PD in animals and humans? These findings contribute to the understanding of the aetiology of periodontal disease in macropods as well as opening up a new direction of research into the microbial interactions involved in the pathogenesis of PD in macropods.

Symmetry: the key to diagnosing propeller strike injuries in sea mammals

The fresh carcass of a neonatal Indo-Pacific bottlenose dolphin (Tursiops aduncus) was recovered from a suburban beach near Adelaide, South Australia, by officers of the Australian Marine Wildlife Research and Rescue Organisation (AMWRO). The carcass was incomplete with loss of the tail and three deep parallel incised/chop wounds to the torso and tail (Fig. 1). At necropsy the carcass was that of an otherwise healthy Indo-Pacific bottlenose dolphin neonate of around 1–2 weeks of age. The animal was normally formed and well nourished, with milk in its mouth and stomach indicating that recent breast feeding had occurred. Frothy white foam was present in the upper airway. The most significant findings consisted of a series of four curvilinear parallel incised/chop wounds predominately to the right side of the body (Fig. 2). The most rostral injury was a clean incised wound of the upper back and right side of the chest which shelved into paraspinal muscles (Fig. 3). No major vessels had been damaged and the chest cavity had not been opened. Within the chest cavity, however, the deepest part of the chop wound was associated with fracture-dislocation of the midthoracic spine (Fig. 4) with spinal cord transaction. There were also fractures of the posterior aspects of the first to sixth ribs on the right side with fresh paravertebal soft tissue hemorrhage bilaterally. Thoracic organs and vessels were intact. Fifty-nine centimeters caudal to this was a second incised/chop wound which passed from the right side through the anterior aspect of the dorsal fin (Figs. 1, 2). Although no body cavities or major vessels had been opened the wound shelved caudally with fracturing of the underlying spine and adjacent fresh interstitial hemorrhage. Caudal to this was a deep curved incised wound that also shelved caudally and extended into paravertebral muscles with a chopping injury to the lateral aspect of the vertebral bodies, with underlying fractures. The final injury consisted of amputation of the tail (Fig. 5). There were no congenital defects, underlying organic diseases or parasitic infestations identified that could have caused or contributed to death. Death was, therefore, due to multiple incised/chop wounds typical of boat propeller injuries with subsequent exsanguination. Amputation of the tail and transaction of the mid thoracic spinal cord would have also have prevented the animal from swimming.

Retrospective Study of Campylobacter Infection in a Zoological Collection

ABSTRACT Little is known about the epidemiology of Campylobacter spp. in wild animal populations. However, zoological collections can provide valuable insights. Using records from the Zoological Society of London Whipsnade Zoo compiled between 1990 and 2003, the roles of a range of biotic and abiotic factors associated with the occurrence of campylobacteriosis were investigated. The occurrence of campylobacteriosis varied widely across host taxonomic orders. Furthermore, in mammals, a combination of changes in both rainfall and temperature in the week preceding the onset of gastroenteritis were associated with isolation of Campylobacter from feces. In birds, there was a weak negative correlation between mean weekly rainfall and isolation of Campylobacter from feces. Importantly, in birds we found that the mean weekly rainfall 3 to 4 weeks before symptoms of gastroenteritis appeared was the best predictor of Campylobacter infection. Campylobacter-related gastroenteritis cases with mixed concurrent infections were positively associated with the presence of parasites (helminths and protozoans) in mammals, while in birds Campylobacter was associated with other concurrent bacterial infections rather than with the presence of helminths and protozoans. This study suggests that climatic elements are important factors associated with Campylobacter-related gastroenteritis. Further investigations are required to improve our understanding of Campylobacter epidemiology in captive wild animal populations.

FIELD IMMOBILIZATION OF FERAL ‘JUDAS’ DONKEYS (EQUUS ASINUS) BY REMOTE INJECTION OF MEDETOMIDINE AND KETAMINE AND ANTAGONISM WITH ATIPAMEZOLE

The Judas technique is a method used for landscape control of feral donkeys (Equus asinus) in northern Australia. Central to the success of any Judas program is the safe, efficient, and humane attachment of the telemetry device. For feral donkeys, this involves the use of field immobilization. We examine the replacement of the current chemical capture agent, succinylcholine, with contemporary immobilization agents to achieve positive animal welfare outcomes. A combination of medetomidine and ketamine delivered by remote injection from a helicopter was used to capture 14 free-ranging feral donkeys for the fitting of telemetry collars in Western Australia in November 2010. Dose rates of 0.14 mg/kg medetomidine and 4.1 mg/kg ketamine were appropriate to immobilize animals in 9 min (±SD=3). Mean recovery time (total time in recumbency) was 21 min (±14). All animals recovered uneventfully after being administered atipamezole, a specific antagonist of medetomidine, intramuscularly at 0.35 mg/kg. Physiologic parameters were recorded during recumbency, with environment-related hyperthermia being the only abnormality recognized. No significant complications were encountered, and this drug combination represents an efficient approach to capturing wild donkeys. This new method allows a rapid, safe, cost-effective approach to the immobilization of feral donkeys for use as Judas animals. This drug combination will replace the relatively inhumane succinylcholine for the field immobilization of feral donkeys.

The potential role of forensic pathologists in veterinary forensic medicine

There has been an increasing awareness over recent years of the field of veterinary forensic medicine, with involvement of veterinarians in a wide range of activities extending from the assessment of possible inflicted injuries in domestic animals to wildlife crime concerning the entrapment, transport and killing of protected and endangered species [1, 2]. More publications are occurring in this area, with for example, a special issue of Forensic Science Medicine and Pathology being recently devoted to wildlife crime, and comprehensive textbooks now emerging [2–4]. The opportunity for forensic pathologists to contribute to this area is also being increasingly recognized [5]. The link between human forensic pathology and that involving animals is obvious and the opportunity to foster collaboration between these two areas of practice should be seized upon, as information and techniques utilized by forensic pathologists may be of great use in veterinary practice. As forensic pathologists are exposed on a daily basis to lethal injuries and processes, they also have a wealth of information that can be shared with veterinary colleagues who may not have such intense exposure to this type of material. It is quite obvious that forensic pathologists with training in human disease and injury have a great deal to learn from veterinary colleagues, and that many of the dissections and conditions encountered will be completely outside their experience. However, certain conditions affecting both humans and animals may show common features, and as lethal episodes in humans may have been studied more extensively than in non-humans, cross-species comparison of cases may provide a useful guide for the possible investigation of nonhuman fatalities. A good example of this was a young adult male Indian Ocean Bottlenose dolphin (Tursiops cf aduncus) that was found dead with a small Cobbler Carpetshark (Sutorectus tentaculatus) wedged firmly within its upper aerodigestive tract. Known as cafe coronary syndrome in humans, this type of death raised the possibility of neurological impairment and prompted a search for intrinsic central nervous system disease, or heavy metal poisoning in the affected animal [6]. The use of human imaging modalities, such as CT scanning, in animals with significant injuries may demonstrate more clearly the nature of the injuries than standard dissection or skeletal defleshing. For example, comminuted fracturing of the midfacial skeleton in a juvenile New Zealand fur seal (Arctocephalus forsteri) was far more clearly shown by CT scanning prior to necropsy than afterwards, as the delicate central facial skeleton had collapsed once supporting fascia and soft tissues had been removed [7]. Unfortunately techniques routinely used in humans, such as immunohistochemical staining of tissues for microscopy using anti-human reagents may not always work in animals [8], although on occasion there may be a surprising degree of cross reactivity [9]. Another area that forensic pathologists can contribute to is in lecturing to veterinary science students on basic injury assessment and evaluation. A patterned abrasion, a stab R. W. Byard (&) Discipline of Anatomy and Pathology, Level 3 Medical School North Building, The University of Adelaide, Frome Road, Adelaide 5005, Australia e-mail: roger.byard@sa.gov.au