Sustained reduction in numbers of Australian fur seal pups: Implications for future population monitoring

PLoS ONE, Journal Year: 2022, Volume and Issue: 17(3), P. e0265610 - e0265610

Published: March 18, 2022

Fur seal populations in the Southern Hemisphere were plundered late 1700s and early 1800s to provide fur for a clothing industry. Millions of seals killed resulting potentially major ecosystem changes across Hemisphere, consequences which are unknown today. Following more than century population suppression, partly through on-going harvesting, many started recover 1900s. Australian ( Arctocephalus pusillus doriferus ), one most geographically constrained species, followed this trend. From 1940s 1986, pup production remained at approximately 10,000 per year, then significant growth commenced. By 2007, live abundance had recovered 21,400 year recovery was expected continue However, species-wide survey 2013 recorded 20% decline, 16,500 pups. It not known if decline due being poor breeding or true reduction. Here we report results population-wide conducted 2017 annual monitoring productive colony, Seal Rocks, Victoria that large (-28%). Sustained lower numbers Rocks from counts between 2012–2017 (mean = 2908 ± 372 SD), as well estimate 16,903 pups 2017, suggest total have level observed 5-yearly census anomalies representative seasons. Potential reasons did occur range-wide but predominantly populated long-standing sites, discussed. To enhance adaptive management methods future also presented. occupy several distinct regions influenced by different currents upwellings: enables comparisons status these regions. Forces driving change likely play other marine ecosystems, particularly where live.

Language: Английский

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Dynamics of Antimicrobial Resistance Carriage in Koalas (Phascolarctos Cinereus) and Pteropid Bats (Pteropus Poliocephalus) Before, During and After Wildfires

Microbial Ecology, Journal Year: 2024, Volume and Issue: 87(1)

Published: Feb. 9, 2024

Abstract In the 2019–2020 summer, wildfires decimated Australian bush environment and impacted wildlife species, including koalas ( Phascolarctos cinereus ) grey headed flying fox pups (Pteropid bats, Pteropus poliocephalus ). Consequently, hundreds of thousands bat entered hospitals with fire-related injuries/illness, where some individuals received antimicrobial therapy. This study investigated dynamics resistance (AMR) in pre-fire, fire-affected post-fire Pteropid pups. PCR DNA sequencing were used to screen samples extracted from faeces (koalas bats) cloacal swabs (koalas) for class 1 integrons, a genetic determinant AMR, identify integron-associated antibiotic genes. Class integrons detected 25.5% (68 267) 59.4% bats (92 155). Integrons contained genes conferring aminoglycosides, trimethoprim beta-lactams. Samples also screened bla TEM (beta-lactam) genes, which 2.6% (7 25.2% (39 Integron occurrence was significantly higher in-care compared wild pre-fire P < 0.0001). not different > 0.05), however, their 0.0001 = 0.0488 respectively). The observed shifts AMR wildfire-impacted species flags need judicious use when treating minimise unwanted selective pressure negative treatment outcomes associated carriage resistant bacteria.

Language: Английский

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High Prevalence of Beta-Lactam-Resistant Escherichia coli in South Australian Grey-Headed Flying Fox Pups (Pteropus poliocephalus)

Microorganisms, Journal Year: 2022, Volume and Issue: 10(8), P. 1589 - 1589

Published: Aug. 7, 2022

The emergence of antimicrobial-resistant Escherichia coli in wildlife is concerning-especially resistance to clinically important beta-lactam antibiotics. Wildlife closer proximity humans, including captivity and rescue/rehabilitation centres, typically have a higher prevalence E. compared their free-living counterparts. Each year, several thousand Australian fruit bat pups, the grey-headed flying fox (GHFF; Pteropus poliocephalus), require rescuing are taken into care by rescue rehabilitation groups. To determine beta-lactam-resistant rescued GHFF pups from South Australia, faecal samples were collected 53 care. A combination selective culture, PCR, antimicrobial susceptibility testing, whole-genome sequencing, phylogenetic analysis was used identify genetically characterise isolates. amoxicillin-, amoxicillin-plus-clavulanic-acid-, cephalosporin-resistant 77.4% (n = 41), 24.5% 13), 11.3% 6), respectively. also carried genes aminoglycosides, trimethoprim plus sulphonamide, tetracyclines 37.7% 20), 35.8% 19), 26.4% 14) respectively, 50.9% 27) multidrug-resistant coli. Twelve strain types identified with six strains having extraintestinal pathogenic traits, indicating that they potential cause blood, lung, or wound infections GHFFs. Two lineages-E. ST963 ST58 O8:H25-were associated human infections. Phylogenetic analyses determined all 12 lineages humans and/or domestic animals. This study demonstrates high transmission anthropogenic-associated entering Importantly, we health risks zoonotic for carers, highlighting need improved antibiotic stewardship biosafety measures

Language: Английский

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Impacts of Domestication and Veterinary Treatment on Mobile Genetic Elements and Resistance Genes in Equine Fecal Bacteria

Applied and Environmental Microbiology, Journal Year: 2023, Volume and Issue: 89(3)

Published: March 7, 2023

Antimicrobial resistance in bacteria is a threat to both human and animal health. We aimed understand the impact of domestication antimicrobial treatment on types numbers resistant bacteria, antibiotic genes (ARGs), class 1 integrons (C1I) equine gut microbiome. Antibiotic-resistant fecal were isolated from wild horses, healthy farm horses undergoing veterinary treatment, isolates (9,083 colonies) screened by PCR for C1I; these found at frequencies 9.8% (vet horses), 0.31% (farm 0.05% (wild horses). A collection 71 unique C1I+ (17 Actinobacteria 54 Proteobacteria) was subjected profiling genome sequencing. Farm yielded mostly C1I+Actinobacteria (Rhodococcus, Micrococcus, Microbacterium, Arthrobacter, Glutamicibacter, Kocuria), while vet primarily C1I+Proteobacteria (Escherichia, Klebsiella, Enterobacter, Pantoea, Acinetobacter, Leclercia, Ochrobactrum); had more extensive stronger PC promoters C1Is. All flanked copies IS6100, except where novel IS5 family element (ISMcte1) implicated mobilization. In Proteobacteria, C1Is predominantly associated with IS26 also IS1, Tn21, Tn1721, Tn512, putative formaldehyde-resistance transposon (Tn7489). Several large C1I-containing plasmid contigs retrieved; two (plasmid Y F) sets metal genes, including copper-resistance (Tn7519). Both increase frequency microflora, each anthropogenic factors selects distinct group integron-containing bacteria. IMPORTANCE There increasing acknowledgment that "one health" approach required tackle growing problem resistance. This requires issue examined not only perspective medicine but includes consideration roles antimicrobials agriculture recognizes importance other ecological compartments dissemination ARGs mobile genetic elements such as C1I. have shown occurrence microflora that, C1I are unexpectedly Actinobacteria, receiving treatments, taxonomic shift occurs, typical Proteobacteria found. identified several new (plasmids, insertion sequences [IS], transposons) genomic

Language: Английский

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Carriage of antibiotic resistance genes to treatments for chlamydial disease in koalas (Phascolarctos cinereus): A comparison of occurrence before and during catastrophic wildfires

One Health, Journal Year: 2023, Volume and Issue: 17, P. 100652 - 100652

Published: Nov. 10, 2023

Growing reports of diverse antibiotic resistance genes in wildlife species around the world symbolises extent this global One Health issue. The health is threatened by antimicrobial situations where develop disease and require antibiotics. Chlamydial a key threat for koalas Australia, with infected frequently entering hospitals requiring therapy, typically chloramphenicol or doxycycline. This study investigated occurrence diversity target doxycycline (cat tet respectively) koala urogenital faecal microbiomes. DNA was extracted from 394 swabs 91 collected mainland Australia on Kangaroo Island (KI) located 14 km off mainland, before (n = 145) during 340) 2019-2020 wildfires. PCR screening sequencing determined 9.9% samples (95%CI: 7.5% to 12.9%) carried cat and/or genes, highest frequency fire-affected KI (16.8%) lowest wild sampled prior fires (6.5%). greater (seven variants detected), compared pre-fire (two detected). Fire-affected care that received antibiotics had significantly higher proportion (p < 0.05) (37.5%) did not receive (9.8%). Of positive koalas, 50.0% were Chlamydia-positive qPCR test. Chloramphenicol microbiomes may contribute negative treatment outcomes receiving anti-chlamydial Thus secondary outcome wildfires increased risk acquisition enter care, potentially exacerbating already significant chlamydial Australia's koalas. highlights importance considering impacts within approach AMR identifies need understanding ecology wildlife.

Language: Английский

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Variations in antimicrobial resistance genes present in the rectal faeces of seals in Scottish and Liverpool Bay coastal waters

Environmental Pollution, Journal Year: 2024, Volume and Issue: 349, P. 123936 - 123936

Published: April 6, 2024

Antibiotic resistance genes originating from human activity are considered important environmental pollutants. Wildlife species can act as sentinels for coastal contamination and in this study we used qPCR array technology to investigate the variety abundance of antimicrobial (ARGs), mobile genetic elements (MGEs) integrons circulating within seal populations both near far large located around Scottish northwest English coast. Rectal swabs were taken 50 live grey seals nine harbour seals. Nucleic acids stabilised upon collection, enabling extraction sufficient quality quantity DNA downstream analysis. 78 ARG targets, including clinical significance, four MGE targets three integron monitor 22 sample pools. 30 ARGs detected, well intl1 intl2 tnpA transposase. Four β-lactam, tetracycline, two phenicol, one trimethoprim, aminoglycoside ten multidrug detected mcr-1 which confers colistin, an drug last resort. No sulphonamide, vancomycin, macrolide, lincosamide or streptogramin B (MLSB) detected. Resistance all sites but highest number (n=29) was samples derived on Isle May, Scotland during breeding season, these also had average relation 16S rRNA gene. This pilot demonstrates effectiveness a culture-independent workflow global analysis microbiota live, free-ranging, wild animals habitats close remote habitation, highlights valuable indicator monitoring presence, land-sea transference between ecosystems.

Language: Английский

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Behavioural Response of Australian Fur Seals (Arctocephalus Pusillus Doriferus) to Vessel Noise During Peak and Off-Peak Human Visitation

Published: Jan. 1, 2024

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Language: Английский

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Behavioural response of Australian fur seals (Arctocephalus pusillus doriferus) to vessel noise during peak and off-peak human visitation

Marine Pollution Bulletin, Journal Year: 2024, Volume and Issue: 208, P. 116947 - 116947

Published: Sept. 14, 2024

Language: Английский

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Contribution of disease to Australian sea lion (Neophoca cinerea) pup mortality at Seal Bay, Kangaroo Island, 2016–2022

Marine Mammal Science, Journal Year: 2024, Volume and Issue: unknown

Published: Nov. 11, 2024

Abstract The endangered Australian sea lion ( Neophoca cinerea ) population is declining, and its conservation threatened by the species' low fecundity high pup mortality. This study details reasons for deaths quantifies impacts of disease comorbidity. Of 284 dead pups reported from five breeding seasons (2016–2022) at Seal Bay colony, Kangaroo Island, gross necropsy was conducted on 122, with fecal analysis hookworm Uncinaria sanguinis detection, tissue histology, bacterial culture performed subsets. Determinable primary causes mortality were conspecific trauma (± comorbidity, 41.0%), starvation (24.6%), infectious (hookworm‐associated hemorrhagic enteritis [HAHE] ± infection, 19.7%). Allowing 37.7% died an disease, including 44.0% 41.5% starvation. In higher summer‐autumn seasons, greater risk p = .001) subsequent infection < .001). Parasiticide treatment significantly reduced HAHE‐associated .005) overall risk, suggesting increases susceptibility to other Although exact causal pathways this treatment‐related benefit remain be confirmed, intervention appears highly impactful could species efforts.

Language: Английский

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Implications of Escherichia coli community diversity in free-ranging Australian pinniped pups

Infection Genetics and Evolution, Journal Year: 2022, Volume and Issue: 104, P. 105351 - 105351

Published: Aug. 17, 2022

Escherichia coli is a widely studied bacterium, commonly used as an indicator of faecal contamination. Investigations into the structure and diversity E. in free-ranging wildlife species has been limited. The objective this study was to characterise intra-individual inter-species phylotype B2 sub-type Australian pinniped pups, determine whether single colony representative these hosts. Faecal samples were collected from fur seal (Arctocephalus pusillus doriferus), sea lion (Neophoca cinerea) long-nosed forsteri) pups three breeding colonies between 2018 2021. swabs thirty randomly selected (n = 10 each species) cultured ten culture based on morphology separation agar plates. Molecular screening techniques utilised assign isolates phylotypes sub-types. There no significant difference (p > 0.05) either or diversity. most dominant, with 78% 234) assigned phylotype. Host factors (species, weight [kg] standard length [cm]) did not significantly affect absence differences at level suggests that could be overall A. p. doriferus, N. cinerea forsteri pups. These findings can simplify improve efficiency sampling protocols for ongoing monitoring human-associated populations.

Language: Английский

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