Metagenomic analysis of gut microbiome and resistome of Whooper and Black Swans: a one health perspective

BACKGROUND

With the promotion of "One Health," the health of animals and their impact on the environment have become major concerns recently. Widely distributed in China, the whooper swans (Cygnus cygnus) and black swans (Cygnus atratus) are not only important to the ecological environment, but they may also potentially influence public health security. The metagenomic approach was adopted to uncover the impacts of the gut microbiota of swans on host and public health.

RESULTS

In this study, the intestinal microbiome and resistome of migratory whooper swans and captive-bred black swans were identified. The results revealed similar gut microbes and functional compositions in whooper and black swans. Interestingly, different bacteria and probiotics were enriched by overwintering whooper swans. We also found that Acinetobacter and Escherichia were significantly enriched in early wintering period swans and that clinically important pathogens were more abundant in black swans. Whooper swans and black swans are potential reservoirs of antibiotic resistance genes (ARGs) and novel ARGs, and the abundance of novel ARGs in whooper swans was significantly higher than that in black swans. Metagenomic assembly-based host tracking revealed that most ARG-carrying contigs originated from Proteobacteria (mainly Gammaproteobacteria).

CONCLUSIONS

The results revealed spatiotemporal changes in microbiome and resistome in swans, providing a reference for safeguarding public health security and preventing animal epidemics.

Emerging markets equities' response to geopolitical risk: Time-frequency evidence from the Russian-Ukrainian conflict era

This study investigates the asymmetric interdependence between geopolitical risk (GPR) and the stock markets of the top-seven emerging (E7) countries (i.e., Mexico, Russia, Turkey, India, China, Indonesia, and Brazil) in the ongoing geopolitical conflict between Russia and Ukraine. With daily datasets covering the period 01-Feb-2022 to 25-July-2022, the squared wavelet coherence (SWC) and wavelet coherence phase difference (WCPD) techniques are employed. The results underscore heterogeneous and asymmetric market-specific coherence and lead-lag patterns regarding E7 stocks' interdependence with geopolitical risk. The findings imply high comovements between Black Swan events like the Russian-Ukrainian conflict and financial markets' volatility, highlighting the essence of alternative assets or asset classes for hedging geopolitical risks in the ongoing military actions. The heterogeneous and asymmetric responses offered by E7 stocks against GPR render emerging markets equities suitable for diversification and downside hedging strategies against GPR-induced shocks. The findings are robust to the time-varying parameter vector autoregression (TVP-VAR) connectedness approach. The results' implications for portfolio managers, investors, and policymakers are discussed.

The swan genome and transcriptome, it is not all black and white

BACKGROUND

The Australian black swan (Cygnus atratus) is an iconic species with contrasting plumage to that of the closely related northern hemisphere white swans. The relative geographic isolation of the black swan may have resulted in a limited immune repertoire and increased susceptibility to infectious diseases, notably infectious diseases from which Australia has been largely shielded. Unlike mallard ducks and the mute swan (Cygnus olor), the black swan is extremely sensitive to highly pathogenic avian influenza. Understanding this susceptibility has been impaired by the absence of any available swan genome and transcriptome information.

RESULTS

Here, we generate the first chromosome-length black and mute swan genomes annotated with transcriptome data, all using long-read based pipelines generated for vertebrate species. We use these genomes and transcriptomes to show that unlike other wild waterfowl, black swans lack an expanded immune gene repertoire, lack a key viral pattern-recognition receptor in endothelial cells and mount a poorly controlled inflammatory response to highly pathogenic avian influenza. We also implicate genetic differences in SLC45A2 gene in the iconic plumage of the black swan.

CONCLUSION

Together, these data suggest that the immune system of the black swan is such that should any avian viral infection become established in its native habitat, the black swan would be in a significant peril.

Disaster Risk Planning With Fuzzy Goal Programming

The uncertainty in the timing and severity of disaster events makes the long-term planning of mitigation and recovery actions both critical and extremely difficult. Planners often use expected values for hazard occurrences, leaving communities vulnerable to worse-than-usual and even so-called "black swan" events. This research models disasters in terms of their best-case, most-likely, and worst-case damage estimates. These values are then embedded in a fuzzy goal programming model to provide community planners and stakeholders with the ability to strategize for any range of events from best-case to worst-case by adjusting goal weights. Examples are given illustrating the modeling approach, and an analysis is provided to illustrate how planners might use the model as a planning tool.

Risking Everything in Obsessive-Compulsive Disorder: An Analogue Decision-Making Study

An experiment examined decision-making processes among nonclinical participants with low or high levels of OCD symptomatology (N = 303). To better simulate the decision environments that are most likely to be problematic for clients with OCD, we employed decision tasks that incorporated "black swan" options that have a very low probability but involve substantial loss. When faced with a choice between a safer option that involved no risk of loss or a riskier alternative with a very low probability of substantial loss, most participants chose the safer option regardless of OCD symptom level. However, when faced with choices between options that had similar expected values to the previous choices, but where each option had some low risk of a substantial loss, there was a significant shift towards riskier decisions. These effects were stronger when the task involved a contamination based, health-relevant decision task as compared to one with financial outcomes. The results suggest that both low and high symptom OC participants approach decisions involving risk-free options and decisions involving risky alternatives in qualitatively different ways. There was some evidence that measures of impulsivity were better predictors of the shift to risky decision making than OCD symptomatology.

Lethal infection caused by Tetratrichomonas gallinarum in black swans (Cygnus atratus)

BACKGROUND

Tetratrichomonas gallinarum is parasitic protozoa with a wide host range. However, its lethal infection is rare reported.

CASE PRESENTATION

Here, we described the first lethal cases of T. gallinarum infection in black swans in China. Five black swans died within a week in succession without obvious symptoms except mild diarrhea. At necropsy, severe lesions were observed in caeca with thickened caecal walls and hemorrhages in the mucosa. A large number of moving trophozoites were found in the contents of the cecum by microscopic examination. The livers were enlarged with multiple bleeding spots on the surface. Histopathology of the livers showed mononuclear cell infiltration and moderate hyperplasia of fibrous tissue. The histopathology of the cecum showed that the villi of the cecum were edematous. Finally, the presence of T. gallinarum was determined by specific PCR andin-situ hybridization assay. Additionally, common pathogens that can cause similar symptoms were excluded.

CONCLUSIONS

The death of the black swan was caused by T. gallinarum, suggesting that the parasite might be a new threat to the Cygnus birds.

Swans and elephants: A typology to capture the challenges of food supply chain risk assessment

As a result of internal or external shocks, food supply chains can transition between existing regimes of assembly and planned activity to situations that are unexpected or unknown. These events can occur without warning, causing stress, shift, even collapse, and impact on business/supply chain viability.

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Black elephants and black swans are of concern in food supply chains.

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Black swans can evolve to grey and white swans with appropriate risk mitigation.

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If supply chain controls become lax, white swans can revert to grey swans.

Dragons, black swans and decisions

Since Nassim Taleb coined black swan as an event that occurred as a complete surprise for everybody, the metaphor of the black swan has been applied to a much wider variety of events. Black swan events now comprise events that are a surprise for some but not for others, events that have a low likelihood, events that were not believed to be possible but still proved to be possible, events that were dismissed as being too improbable to worry about but happened anyway. For a decision maker the black swan problem is choosing where to put effort to prevent, or mitigate events for which there are warnings, or for which the possibility has been put forward. Does the fact that there are thousands of books written about fire breathing dragons warrant the development of an Anti-Dragon Defense Shield? The black swan may have been a surprise for Willem de Vlamingh in 1697, it was not a surprise for the inhabitants of Australia, for which the appearance of tall white humans was their "black swan event". In this paper we explore the options available to decision makers when confronted with the various sorts of swan (or dragon) events.

First sporadic case of pathogenic Escherichia coli infection in Black swan in China

A strain of bacteria was isolated from the diseased black swan (Cygnus atratus) died from enteritis diarrhea, and designated tentatively as B-1 strain. Morphological and biochemical tests, as well as phylogenetic analysis derived from 16S rRNA and fimC gene sequencing both strongly indicated that B-1 strain is identical to Escherichia coli. Furthermore, the polymerase chain reaction single-strand conformation polymorphism (PCR-SSCP) profile of the isolate was different from that of two reference strains. Antibiotic sensitivity testing of B-1 strain was carried out by the standard Kirby-Bauer disc diffusion method. Animal experiments demonstrated that B-1 strain is pathogenic to mice and chickens. This is first sporadic case of pathogenic E. coli infection in Black swan in China.

Respiratory tract infection caused by Mycobacterium bovis in a black swan (Cygnus atratus)

A 3-year-old male black swan (Cygnus atratus), belonging to a private collection, died suddenly and was subjected to post mortem examination. At necropsy, caseous exudate was observed in the lungs and air sacs; granulomatous lesions characterized by epithelioid macrophages and abundant mycobacteria were observed microscopically. Avian tuberculosis associated with Mycobacterium bovis was confirmed by bacteriologic isolation, biochemical tests and molecular methods. The organism was identified as spoligotype SB0140, which is frequently found in cattle and people in North America. In this case, interspecies transmission could have been the source of infection because the swan cohabited with cattle.