Electrical impedance tomography in anaesthetised chickens (Gallus domesticus).

The applicability of electrical impedance tomography (EIT) in birds is unknown. This study aimed to evaluate the use of EIT in anaesthetised chickens in four recumbency positions. Four adult Hyline chickens were anaesthetised with isoflurane in oxygen, and intubated endotracheally for computed tomography (CT). A rubber belt was placed around the coelom caudal to the shoulder joint. A chicken-specific finite element (FE) model, which is essential to generate anatomically accurate functional EIT images for analysis, was constructed based on the CT images obtained at the belt level. Ten additional chickens were anaesthetised with the same protocol. An EIT electrode belt was placed at the same location. The chickens were breathing spontaneously and positioned in dorsal, ventral, right and left lateral recumbency in a randomised order. For each recumbency, raw EIT data were collected over 2 min after 13 min of stabilisation. The data were reconstructed into functional EIT images. EIT variables including tidal impedance variation (TIV), centre of ventilation right to left (CoVRL) and ventral to dorsal (CoVVD), right to left (RL) ratio, impedance change (ΔZ) and eight regional impedance changes including the dorsal, central-dorsal, central-ventral and ventral regions of the right and left regions were analysed. Four breathing patterns (BrP) were observed and categorised based on the expiratory curve. A linear mixed model was used to compare EIT variables between recumbencies. Fisher's exact test was used to compare the frequencies of breathing patterns for each recumbency. The ΔZ observed was synchronous to ventilation, and represented tidal volume of the cranial air sacs as confirmed by CT. Significant differences were found in CoVVD and regional impedance changes between dorsal and ventral recumbencies (P < 0.05), and in CoVRL, RL ratio and regional impedance changes between right and left recumbencies (P < 0.05), which suggested a tendency for the distribution of ventilation to shift towards non-dependent air sacs. No differences were found for TIV and respiratory rate between recumbencies. Recumbency had a significant effect on the frequencies of each of the four BrPs (P = 0.001). EIT can monitor the magnitude and distribution of ventilation of the cranial air sacs in different recumbencies in anaesthetised chickens.

Uncontrolled pain: a call for better study design.

Studies assessing animal pain in veterinary research are often performed primarily for the benefit of animals. Frequently, the goal of these studies is to determine whether the analgesic effect of a novel treatment is clinically meaningful, and therefore has the capacity to improve the welfare of treated animals. To determine the treatment effect of a potential analgesic, control groups are necessary to allow comparison. There are negative control groups (where pain is unattenuated) and positive control groups (where pain is attenuated). Arising out of animal welfare concerns, there is growing reluctance to use negative control groups in pain studies. But for studies where pain is experimentally induced, the absence of a negative control group removes the opportunity to demonstrate that the study methods could differentiate a positive control intervention from doing nothing at all. For studies that are controlled by a single comparison group, the capacity to distinguish treatment effects from experimental noise is more difficult; especially considering that pain studies often involve small sample sizes, small and variable treatment effects, systematic error and use pain assessment measures that are unreliable. Due to these limitations, and with a focus on farm animals, we argue that many pain studies would be enhanced by the simultaneous inclusion of positive and negative control groups. This would help provide study-specific definitions of pain and pain attenuation, thereby permitting more reliable estimates of treatment effects. Adoption of our suggested refinements could improve animal welfare outcomes for millions of animals globally.

Biological Variation in Biochemistry Analytes in Laboratory Guinea Pigs (Cavia porcellus).

Biological variation (BV) describes the physiological random fluctuation around a homeostatic set point, which is a characteristic of all blood measurands (analytes). That variation may impact the clinical relevance of the changes that are observed in the serial results for an individual. Biological variation is represented mathematically by the coefficient of variation (CV) and occurs within each individual (CVI) and between individuals in a population (CVG). Biological variation data can be used to assess whether population-based reference or subject-based reference intervals should be used for the interpretation of laboratory results through the calculation of the index of individuality (IoI). This study aimed to determine the biological variations, calculate the IoI and reference change values (RCV) of clinical chemistry analytes in an outbred strain colony of Hartley guinea pigs (GPs), and set the quality specifications for clinical chemistry analytes. Blood was collected from 16 healthy adult laboratory colony GPs via jugular venipuncture at weekly intervals over six weeks. All the samples were frozen and analyzed in a single run. Analytical, CVI, and CVG biological variations, together with the IoI and RCV, were calculated for each measurand. Based on the estimated BV, the calculated IoI was low for glucose, so individual reference intervals (RCV) should be used. The majority of the measurands should be interpreted using both population-based and subject-based reference intervals as the IoIs were intermediate.

ICTV Virus Taxonomy Profile: Sunviridae 2023.

Sunviridae is a family of negative-sense RNA viruses with genomes of about 17.2 kb that have been found in snakes. The sunvirid genome comprises nonsegmented RNA with six open reading frames (ORFs) >1 kb that are predicted to encode six proteins. This is a summary of the International Committee on Taxonomy of Viruses (ICTV) Report on the family Sunviridae, which is available at ictv.global/report/sunviridae.

The effect of doxapram on survival and APGAR score in newborn puppies delivered by elective caesarean: A randomized controlled trial.

Doxapram is marketed as a respiratory stimulant and is used by some veterinarians to help with neonatal apnoea, especially in puppies delivered by caesarean. There is a lack of consensus as to whether the drug is effective and data on its safety are limited. Doxapram was compared to placebo (saline) in newborn puppies in a randomized, double-blinded clinical trial using two outcome measures: 7-day mortality rate and repeated APGAR score measurements. Higher APGAR scores have been positively correlated with survival and other health outcomes in newborns. Puppies were delivered by caesarean and a baseline APGAR score was measured. This was immediately followed by a randomly allocated intralingual injection of either doxapram or isotonic saline (of the same volume). Injection volumes were determined by the weight of the puppy and each injection was administered within a minute of birth. The mean dose of doxapram administered was 10.65 mg/kg. APGAR scores were measured again at 2, 5, 10 and 20 min. One hundred and seventy-one puppies from 45 elective caesareans were recruited into this study. Five out of 85 puppies died after receiving saline and 7 out of 86 died after receiving doxapram. Adjusting for the baseline APGAR score, the age of the mother and whether the puppy was a brachycephalic breed, there was insufficient evidence to conclude a difference in the odds of 7-day survival for puppies that received doxapram compared to those that received saline (p = .634). Adjusting for the baseline APGAR score, the weight of the mother, the litter size, the mother's parity number, the weight of the puppy and whether the puppy was a brachycephalic breed, there was insufficient evidence to conclude a difference in the probability of a puppy having an APGAR score of ten (the maximum APGAR score) between those that received doxapram compared to those that received saline (p = .631). Being a brachycephalic breed was not associated with an increased odds of 7-day mortality (p = .156) but the effect of the baseline APGAR score on the probability of having an APGAR score of ten was higher for brachycephalic than non-brachycephalic breeds (p = .01). There was insufficient evidence that intralingual doxapram provided an advantage (or disadvantage) compared to intralingual saline when used routinely in puppies delivered by elective caesarean and that were not apnoeic.

A review of reptile virus experimental infection studies.

Despite recent advances in molecular techniques, infection studies remain an important tool for biosecurity, veterinary and conservation medicines. Experimental infection studies are performed for many reasons: to investigate causal links between pathogens and disease, to study host species susceptibility, to study immune response to inoculation, to investigate pathogen transmission and to investigate methods for infection control. Experimental infection studies using viruses in reptiles have been conducted sporadically since at least the 1930s and this continues to be a fertile area of research. This review catalogues previously published research in the field. The key parameters of each study are tabulated, providing a summary of more than 100 experiments linked to their original publications. Common themes and trends within the data are discussed.

Use of a Low-calorie Flavored Gel to Facilitate Oral Self-administration of Analgesics in Mice.

The goals of this study were to determine whether mice would adapt to a low-calorie flavored water gel as their sole source of hydration and whether the addition of acetaminophen, tramadol, meloxicam, or buprenorphine to the gel would affect their intake. Water and gel intakes were measured during a 4-phase study, each of which lasted 1 wk: phase 1, standard water bottle only; phase 2, standard water bottle and a separate tube containing water gel; phase 3, water gel only; and phase 4, water gel containing an analgesic drug. Water consumption, corrected for body mass, was not different between male and female mice when water was available (phases 1 and 2). However, the total consumption of water and water gel was higher for females than males during phase 2, and female mice consumed more gel than males during phase 3. When male and female data were combined, total corrected water intake was not different among the first 3 phases of the study. Gel intake did not change significantly after the addition of acetaminophen, meloxicam, buprenorphine or tramadol as compared with untreated water gel. These data suggest that drugs presented in the low-calorie flavored water gel may be a viable alternative to injection or gavage for the administration of analgesic drugs.

Elevated lead exposure in Australian hunting dogs during a deer hunting season.

There is growing recognition of the threat posed by toxic lead-based ammunition. One group of domestic animals known to be susceptible to harmful lead exposure via this route is hunting dogs. Scent-trailing dogs ('hounds') are used to hunt introduced sambar deer (Cervus unicolor) during a prescribed eight-month (April-November) annual hunting season, during which they are fed fresh venison, in Victoria, south-eastern Australia. We used this annual season as a natural experiment to undertake longitudinal sampling of dogs for lead exposure. Blood was collected from 27 dogs owned by four different deer hunters and comprising three different breeds just prior to the start of the hound hunting season (March 2022) and in the middle of the season (August 2022), and blood lead levels (BLLs) (µg/dL) were determined via inductively coupled plasma mass spectrometry (ICP-MS). Using Tobit regression, the expected BLLs across all dogs were significantly lower before the season (0.50 µg/dL, standard error [SE] = 0.32 µg/dL) than during the season (1.39 µg/dL, SE = 0.35 µg/dL) (p = 0.01). However, when the breed of dog was included in the analyses, this effect was only significant in beagles (P < 0.001), not bloodhounds (p = 0.73) or harriers (p = 0.43). For 32% of the dogs before the season, and 56% during the season, BLLs exceeded the established threshold concentration for developmental neurotoxicity in humans (1.2 µg/dL). Time since most recent venison feeding, sex of dog and owner were not associated with BLLs. The finding that BLLs more than doubled during the hunting season indicates that lead exposure is a risk in this context. These results expand the sphere of impact from environmental lead in Australia from wild animals and humans, to include some groups of domestic animals, a textbook example of a One Health issue.

Rethinking the utility of the Five Domains model.

The Five Domains model is influential in contemporary studies of animal welfare. It was originally presented as a conceptual model to understand the types of impact that procedures may impose on experimental animals. Its application has since broadened to cover a wide range of animal species and forms of animal use. However, it has also increasingly been applied as an animal welfare assessment tool, which is the focus of this paper. Several critical limitations associated with this approach have not been widely acknowledged, including that: (1) it relies upon expert or stakeholder opinion, with little transparency around the selection of these individuals; (2) quantitative scoring is typically attempted despite the absence of clear principles for aggregation of welfare measures and few attempts to account for uncertainty; (3) there have been few efforts to measure the repeatability of findings; and (4) it does not consider indirect and unintentional impacts such as those imposed on non-target animals. These deficiencies lead to concerns surrounding testability, repeatability and the potential for manipulation. We provide suggestions for refinement of how the Five Domains model is applied to partially address these limitations. We argue that the Five Domains model is useful for systematic consideration of all sources of possible welfare compromise and enhancement, but is not, in its current state, fit-for-purpose as an assessment tool. We argue for wider acknowledgment of the operational limits of using the model as an assessment tool, prioritisation of the studies needed for its validation, and encourage improvements to this approach.

Metal(loid) pollution, not urbanisation nor parasites predicts low body condition in a wetland bioindicator snake.

Urban ecosystems and remnant habitat 'islands' therein, provide important strongholds for many wildlife species including those of conservation significance. However, the persistence of these habitats can be undermined if their structure and function are too severely disrupted. Urban wetlands, specifically, are usually degraded by a monoculture of invasive vegetation, disrupted hydrology, and chronic-contamination from a suite of anthropogenic pollutants. Top predators-as bioindicators-can be used to assess and monitor the health of these ecosystems. We measured eight health parameters (e.g., parasites, wounds and scars, tail loss and body condition) in a wetland top predator, the western tiger snake, Notechis scutatus occidentalis. For three years, snakes were sampled across four wetlands along an urban gradient. For each site, we used GIS software to measure the area of different landscapes and calculate an urbanisation-landscape score. Previously published research on snake contamination informed our calculations of a metal-pollution index for each site. We used generalised linear mixed models to assess the relationship between all health parameters and site variables. We found the metal-pollution index to have the most significant association with poor body condition. Although parasitism, tail loss and wounds differed among sites, none of these parameters influenced body condition. Additionally, the suite of health parameters suggested differing health status among sites; however, our measure of contemporary landscape urbanisation was never a significant predictor variable. Our results suggest that the health of wetland predators surrounding a rapidly growing city may be offset by higher levels of environmental pollution.

ICTV Virus Taxonomy Profile: Bornaviridae.

Members of the family Bornaviridae produce enveloped virions containing a linear negative-sense non-segmented RNA genome of about 9 kb. Bornaviruses are found in mammals, birds, reptiles and fish. The most-studied viruses with public health and veterinary impact are Borna disease virus 1 and variegated squirrel bornavirus 1, both of which cause fatal encephalitis in humans. Several orthobornaviruses cause neurological and intestinal disorders in birds, mostly parrots. Endogenous bornavirus-like sequences occur in the genomes of various animals. This is a summary of the International Committee on Taxonomy of Viruses (ICTV) Report on the family Bornaviridae, which is available at ictv.global/report/bornaviridae.

A WIDESPREAD NOVEL GAMMAHERPESVIRUS IN APPARENTLY HEALTHY WILD QUOKKAS (SETONIX BRACHYURUS): A THREATENED AND ENDEMIC WALLABY OF WESTERN AUSTRALIA.

Five genetically distinct macropodid marsupial herpesviruses have been reported [Macropodid alphaherpesviruses 1 and 2 (MaHV-1 and -2); Macropodid herpesviruses 3 to 5 (MaHV-3 to -5)]. MaHV-2 was originally isolated from an outbreak of fatal disease in captive quokkas (Setonix brachyurus) that were in contact with other macropodid species. This warranted a survey of the presence of herpesviruses in this threatened and endemic Western Australian (WA) wallaby. Blood samples from 142 apparently healthy quokkas were tested for exposure to MaHV-1 and -2 by serology. Of these 142, 121 [Rottnest Island (RI), n = 93; mainland WA, n = 28] were tested for herpesvirus infection by polymerase chain reaction (PCR). Antibodies to MaHV-1 and -2 were detected in one individual [prevalence, 0.7%; 95% confidence interval (CI), 0.1%-3.2%] from the mainland and none from RI. However, a novel gammaherpesvirus [designated Macropodid herpesvirus 6 (MaHV-6)] was detected by PCR in the blood of 13 of 121 individuals (11%; 95% CI, 6.2-17.2). Infection with MaHV-6 was significantly more prevalent on the mainland (7/28; i.e., 25%) compared with RI (6/93; i.e., 6.45%; difference in sample proportions, 95% CI, 6%-32%; P = 0.015). There was no association (P > 0.05) between infection with MaHV-6 and differences in hematology, blood chemistry, peripheral blood cell morphologies, or on clinical status. There was a significant association between infection with MaHV-6 and the presence of Theileria spp. in blood [odds ratio (OR) = 11.0; 95% CI, 2.31-52.3; P = 0.001] and yeast in the nasal lining (OR = 7.0; 95% CI, 1.54-31.8; P = 0.021), suggesting that quokkas may be more susceptible to infection with these microorganisms if also infected with MaHV-6. MaHV-6 infection may be a catalyst for vulnerability to disease with other infectious agents and may pose a significant threat to other macropods. These findings have implications for in situ and ex situ management programs of quokkas.

MICROSPORIDIA-ASSOCIATED GRANULOMATOUS DISEASE IN TWO AUSTRALIAN COLLECTIONS OF CAPTIVE INLAND BEARDED DRAGONS (POGONA VITTICEPS).

Microsporidia are obligate, intracellular fungi. In reptiles, they are most commonly reported in squamates. We report the first detection of microsporidiosis in inland bearded dragons (Pogona vitticeps) from Australia, and for the first time, mixed infections of microsporidium and adenovirus in asymptomatic inland bearded dragons. In one collection there were five individuals, one of which was lethargic, inappetent, and had lost weight. Two large ovarian granulomas were palpated (42 × 23 mm and 26 × 19 mm) and were surgically removed. This animal died shortly after surgery. Histological evaluation of these granulomas revealed granulomatous inflammation within or adjacent to ovarian tissue, containing numerous aggregates of microorganisms consistent with microsporidia. The organisms were confirmed as Encephalitozoon pogonae by polymerase chain reaction (PCR) and sequencing. Agamid adenovirus-1 was also detected. These two infectious agents were also detected by PCR in all the other bearded dragons in this collection (n = 5), all of which were asymptomatic. A single dragon from a second collection presented for a routine wellness examination after the sudden death of another dragon in the collection. This dragon had similar intracelomic masses to the dragon from the first collection. These were removed surgically, but the dragon died 5 wk later following 3 wk of treatment with 25 mg/kg fenbendazole PO q7 days. Necropsy samples were collected and the microsporidian Encephalitozoon pogonae was detected in oral-cloacal swabs, blood, and multiple tissues by PCR and sequencing. Agamid adenovirus-1 was not detected in this dragon.

Animal Harms and Food Production: Informing Ethical Choices.

Ethical food choices have become an important societal theme in post-industrial countries. Many consumers are particularly interested in the animal welfare implications of the various foods they may choose to consume. However, concepts in animal welfare are rapidly evolving towards consideration of all animals (including wildlife) in contemporary approaches such as "One Welfare". This approach requires recognition that negative impacts (harms) may be intentional and obvious (e.g., slaughter of livestock) but also include the under-appreciated indirect or unintentional harms that often impact wildlife (e.g., land clearing). This is especially true in the Anthropocene, where impacts on non-human life are almost ubiquitous across all human activities. We applied the "harms" model of animal welfare assessment to several common food production systems and provide a framework for assessing the breadth (not intensity) of harms imposed. We considered all harms caused to wild as well as domestic animals, both direct effects and indirect effects. We described 21 forms of harm and considered how they applied to 16 forms of food production. Our analysis suggests that all food production systems harm animals to some degree and that the majority of these harms affect wildlife, not livestock. We conclude that the food production systems likely to impose the greatest overall breadth of harms to animals are intensive animal agriculture industries (e.g., dairy) that rely on a secondary food production system (e.g., cropping), while harvesting of locally available wild plants, mushrooms or seaweed is likely to impose the least harms. We present this conceptual analysis as a resource for those who want to begin considering the complex animal welfare trade-offs involved in their food choices.

Meta-Transcriptomic Discovery of a Divergent Circovirus and a Chaphamaparvovirus in Captive Reptiles with Proliferative Respiratory Syndrome.

Viral pathogens are being increasingly described in association with mass morbidity and mortality events in reptiles. However, our knowledge of reptile viruses remains limited. Herein, we describe the meta-transcriptomic investigation of a mass morbidity and mortality event in a colony of central bearded dragons (Pogona vitticeps) in 2014. Severe, extensive proliferation of the respiratory epithelium was consistently found in affected dragons. Similar proliferative lung lesions were identified in bearded dragons from the same colony in 2020 in association with increased intermittent mortality. Total RNA sequencing identified two divergent DNA viruses: a reptile-infecting circovirus, denoted bearded dragon circovirus (BDCV), and the first exogeneous reptilian chaphamaparvovirus-bearded dragon chaphamaparvovirus (BDchPV). Phylogenetic analysis revealed that BDCV was most closely related to bat-associated circoviruses, exhibiting 70% amino acid sequence identity in the Replicase (Rep) protein. In contrast, in the nonstructural (NS) protein, the newly discovered BDchPV showed approximately 31%-35% identity to parvoviruses obtained from tilapia fish and crocodiles in China. Subsequent specific PCR assays revealed BDCV and BDchPV in both diseased and apparently normal captive reptiles, although only BDCV was found in those animals with proliferative pulmonary lesions and respiratory disease. This study expands our understanding of viral diversity in captive reptiles.

Haematology and blood chemistry in free-ranging quokkas (Setonix brachyurus): Reference intervals and assessing the effects of site, sampling time, and infectious agents.

Quokkas (Setonix brachyurus) are small macropodid marsupials from Western Australia, which are identified as of conservation concern. Studies on their blood analytes exist but involve small sample sizes and are associated with very little information concerning the health of the animals. Blood was collected from free-ranging quokkas from Rottnest Island (n = 113) and mainland (n = 37) Western Australia, between September 2010 and December 2011, to establish haematology and blood chemistry reference intervals. Differences in haematology and blood chemistry between sites (Rottnest Island v mainland) were significant for haematology (HMT, p = 0.003), blood chemistry (BLC, p = 0.001) and peripheral blood cell morphology (PBCM, p = 0.001). Except for alkaline phosphatase, all blood chemistry analytes were higher in mainland animals. There were also differences with time of year in HMT (p = 0.001), BLC (p = 0.001) and PBCM (p = 0.001) for Rottnest Island quokkas. A small sample of captive animals (n = 8) were opportunistically sampled for plasma concentrations of vitamin E and were found to be deficient compared with wild-caught animals. Fifty-eight of the 150 quokkas were also tested for the presence of Salmonella, microfilariae, Macropodid herpesvirus-6, Theileria spp., Babesia spp., trypanosomes, Cryptococcus spp. and other saprophytic fungi. All eight infectious agents were detected in this study. Infectious agents were detected in 24 of these 58 quokkas (41%), with more than one infectious agent detected for all 24 individuals. Salmonella were detected concurrently with microfilariae in 8 of these 24 quokkas, and this mixed infection was associated with lower values across all haematological analytes, with Salmonella having the greater involvement in the decreased haematological values (p < 0.05). There was no evidence for an effect of sex on HMT, BLC and PBCM. Our data provide important haematological and blood chemistry reference intervals for free-ranging quokkas. We applied novel methods of analyses to HMT and BLC that can be used more broadly, aiding identification of potential disease in wildlife.

Estradiol-17ß Pharmacokinetics and Histological Assessment of the Ovaries and Uterine Horns following Intramuscular Administration of Estradiol Cypionate in Feral Cats.

The control of feral cats (Felis catus) in Australia is a key biological conservation issue. Male cats are more difficult to control than female cats. Collared and tagged female cats displaying estrous behavior have been considered as a way to lure male cats and reveal their locations. As female cats are seasonal breeders, artificial induction of estrous behavior following the administration of a long-acting estrogen could improve their use for this purpose. Estradiol cypionate was intramuscularly administered to nine entire non-pregnant female feral cats, of unknown estrous status, at 0.1, 0.3, or 0.5 mg/kg. Mean peak serum concentrations of estradiol-17ß were 365 pg/mL (0.1 mg/kg), 1281 pg/mL (0.3 mg/kg), and 1447 pg/mL (0.5 mg/kg). The time-course of estradiol-17ß concentrations after various doses of estradiol cypionate was assessed using non-compartmental and non-linear mixed-effects methods. At the highest-studied dose (0.5 mg/kg), the 50th percentile of estradiol-17ß concentrations exceeded 0.1 ng/mL for 11.8 days, and 0.05 ng/mL for 14.6 days. The duration increased with increasing dose. No signs of toxicity were noticed in any cat during the study. This information will be useful to ongoing studies that are investigating ways to reduce the abundance of feral cats in Australia, especially adult male cats.

The Pharmacokinetics of Medetomidine Administered Subcutaneously during Isoflurane Anaesthesia in Sprague-Dawley Rats.

Anaesthetic protocols involving the combined use of a sedative agent, medetomidine, and an anaesthetic agent, isoflurane, are increasingly being used in functional magnetic resonance imaging (fMRI) studies of the rodent brain. Despite the popularity of this combination, a standardised protocol for the combined use of medetomidine and isoflurane has not been established, resulting in inconsistencies in the reported use of these drugs. This study investigated the pharmacokinetic detail required to standardise the use of medetomidine and isoflurane in rat brain fMRI studies. Using mass spectrometry, serum concentrations of medetomidine were determined in Sprague-Dawley rats during medetomidine and isoflurane anaesthesia. The serum concentration of medetomidine for administration with 0.5% (vapouriser setting) isoflurane was found to be 14.4 ng/mL (±3.0 ng/mL). The data suggests that a steady state serum concentration of medetomidine when administered with 0.5% (vapouriser setting) isoflurane can be achieved with an initial subcutaneous (SC) dose of 0.12 mg/kg of medetomidine followed by a 0.08 mg/kg/h SC infusion of medetomidine. Consideration of these results for future studies will facilitate standardisation of medetomidine and isoflurane anaesthetic protocols during fMRI data acquisition.

Salmonella in Free-Ranging Quokkas (Setonix brachyurus) from Rottnest Island and the Mainland of Western Australia.

Salmonella is a genus of Gram-negative, motile, and facultative anaerobic bacteria with a worldwide distribution that contaminates multiple substrates (vegetation, food, soil, and water) and inhabits the gastrointestinal tract of birds, reptiles, and mammals, including humans. Rottnest Island is a popular tourist destination and is abundantly inhabited by quokkas (Setonix brachyurus), a charismatic small wallaby. Current data on the association between Salmonella and quokkas on Rottnest Island are outdated by approximately 30 years. Additionally, previous studies on quokkas on this island and mainland Western Australia did not perform physical examinations or any diagnostic tests. The aim of the project was to assess the prevalence of Salmonella spp. in quokkas from Rottnest Island and mainland Western Australia and correlate the presence of the bacterium with the health of the animal. Ninety-two quokkas from Rottnest Island (n = 71) and populations on the mainland (n = 21) were screened for Salmonella, and a prevalence of 47.9% and 4.8%, respectively, was determined. A total of 16 serovars were identified from 37 isolates; five of these serovars had previously not been described in the quokka. Salmonella appeared to have an effect on the haematology and blood chemistry of quokkas on Rottnest Island consistent with subclinical salmonellosis. The health of Rottnest Island quokkas, and their potential impact on the health of the visitors to the island, should continue to be monitored carefully.

Comparison of three different PCR protocols for the detection of ferlaviruses.

BACKGROUND: Ferlaviruses are important pathogens in snakes often associated with respiratory and neurological disease. The detection of ferlaviral RNA by PCR is considered to be the most reliable method for the diagnosis of infection. The PCRs that have been used most commonly for this purpose have not been properly assessed to determine their sensitivity, specificity and ability to detect the known genetic diversity of this group of viruses. The aim of this study was to compare three published PCR protocols so that a single method could be recommended to laboratories that perform this testing. RESULTS: Comparisons were carried out using cell culture isolates and tissues from snakes infected with specific virus genotypes. A single round PCR targeting a short segment of the viral polymerase (L) gene provided the highest sensitivity and specificity, and detected isolated ferlaviruses from all four described genogroups, as well as from tissues of infected snakes. CONCLUSION: A broadly-reactive PCR for the detection of all known ferlaviruses was found to provide a good combination of detection limit, specificity and speed. Based on these criteria, this method is recommended for the diagnosis of ferlavirus infections.