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International audience; Assessing the relationship between grassland plant diversity and agronomic value is a major challenge to reconcile nature conservation and agricultural use of extensive grassland habitats. To do this, multiple facets of forage production must be considered such as the quantity produced and its nutritive value, commonly assessed through its digestibility, energy content, and nutrient content. The aim of this study was to analyse the effects of plant diversity and functional traits on forage productivity and nutritive value in a wide set of semi-natural grassland habitats.Forage was sampled in 202 plots located across 68 permanent extensive grasslands in eight regions of France. Species and functional diversity indices, community-weighted means (CWM) of plant functional traits, and the relative cover of main plant functional types (PFT; graminoids, forbs, and legumes) were used to describe plant communities. Forage production was evaluated by recording early standing biomass (SB), and nutritive value parameters, namely digestibility (DMD), crude protein content (CP), and average mineral content (MinAv) at the beginning of the vegetation growing season.Species richness was negatively associated with SB and MinAv. Species evenness was positively correlated with CP, DMD, and MinAv, while PFT evenness was positively correlated with CP and DMD. Forage standing biomass increased with increasing graminoid cover and decreased with increasing forb cover. A higher legume cover and specific leaf area CWM as well as a lower leaf dry matter content CWM was associated with improved forage nutritive value and had no effect on SB. Our results highlight that a better forage nutritive value can be obtained with a higher plant species evenness in permanent grassland habitats. Furthermore, in grasslands with an even distribution of plant functional types, forage nutritive value may be improved with no loss in early standing biomass.

Dès lors que le collapsus trachéal est diagnostiqué chez le chien, une prise en charge médicale et conservatrice peut être envisagée dans la plupart des cas, fondée sur des traitements symptomatiques (antitussifs, anti-inflammatoires) et des mesures hygiéniques (contrôle du poids entre autres). Une approche interventionnelle doit toutefois être considérée pour les collapsus graves ou les cas réfractaires. Afin de pallier les nombreuses complications initialement associées à la pose chirurgicale d’anneaux extratrachéaux, le développement de stents endotrachéaux, il y a une vingtaine d’années, a constitué une véritable révolution thérapeutique associée à de bons résultats cliniques. Les complications de cette technique restent toutefois nombreuses, bien que de plus en plus limitées par la bonne sélection du patient, le choix du stent idéal et l’expérience croissante des manipulateurs. Toutefois, des données récentes suggèrent que le traitement chirurgical demeure une technique intéressante, moins onéreuse et alternative à la pose des stents, au moins dans les collapsus extrathoraciques. Dans tous les cas, le choix du type de traitement dépend de l’ensemble du tableau clinique du patient, des comorbidités, du type et de l’étendue du collapsus, et de la préférence du clinicien.

A dog was examined because of acute onset of respiratory distress following a cervical dog bite. Physical examination revealed a deep ventral cervical bite wound associated with localized mild subcutaneous emphysema. Thoracic radiographs showed moderate pneumomediastinum. Medical management consisting of oxygen therapy, antibiotics, and anti-inflammatories was initiated. After 2 days, respiratory distress suddenly worsened. Tracheoscopy showed a discontinuity between the tracheal rings of the cervical trachea; however, the inner tracheal wall appeared intact. Computed tomography scan revealed a ~3-cm complete rupture of all layers of the trachea. Surgical resection and anastomosis of the trachea were performed successfully. Follow-up 15 days after surgery showed complete resolution of respiratory signs, as well as subcutaneous emphysema. A mild ventral angulation of the trachea at the surgical site was noticed on thoracic radiographs. This is the first case report of a pseudotrachea in a dog. Persistence of a pseudotrachea may initially result in only minor clinical signs responsive to medical therapy despite tracheal rupture. In the presence of a pseudotrachea, tracheal rupture may be difficult to identify with tracheoscopy alone. Therefore, CT scan should be proposed in every patient with suspected tracheal trauma. Key clinical message: This case report highlights the importance of including a tracheal rupture in the differential diagnosis of cervical subcutaneous emphysema, even if the amount is small and not associated with significant respiratory signs. The presence of a pseudotrachea may result in less severe clinical signs than expected based on the actual degree of tracheal injury; however, the clinical status may rapidly deteriorate and become life-threatening. This case report also underlines the importance of a CT scan as a complement to tracheoscopy, which may not be sufficient to identify a tracheal rupture in the presence of a pseudotrachea.

International audience

International audience

Wildlife species are harvested for a variety of purposes. This is known to drive phenotypic change, particularly in the context of exploitative harvesting. As the impact of invasive alien species grows, and new conflicts with nuisance species arise, management of these problematic species has emerged as a key topic. Yet there is little to no attention directed to whether and how species are changing as a consequence of lethal control, particularly in terms of their behavior. In this synthesis, we draw attention to the fact that nuisance and invasive species undergoing control are likely to exhibit behavioral change. First, we highlight the potential consequences of behavioral responses to control on species’ management and ecological impact. Second, we provide a framework of mechanisms that can lead to behavioral responses to lethal control. Three categories are described: evolutionary mechanisms, cognitive mechanisms, and stress mechanisms. Understanding which mechanism underlies a behavioral response is paramount as it allows to predict how prevalent the response will be in the population. We argue for increased monitoring of behavior by managers and more research efforts into the mechanisms of behavioral responses to novel threats in order to better predict and mitigate unforeseen and unwanted behavioral change.

5G will provide a flexible and programmable infrastructure, allowing different networks to share the same access network. A way to respond to the diverse service requirements of 5G while reducing both CAPEX and OPEX is to adopt cloud-native architectures. In this context, micro-services software design, the corner stone of cloud-native architecture, seems to be ideal for 5G. However, despite its several advantages, micro-services raise new challenges which slow its adoption down in the NFV ecosystem. Indeed, steering the expected 5G traffic between cloud-native network function is extremely challenging and is still under-investigated. In this paper, we address the service function chaining (SFC) in micro-service based network function virtualization (NFV) ecosystem from the view of the traffic steering. Specifically, we design and implement a cloud-native SFC framework offering efficient traffic steering mechanisms while considering the network state of the underlying NFV infrastructure. In this context, an optimized network-aware load balancing strategy is proposed. Based on extensive experiments, the results obtained show that our strategy achieved good results in terms of i) end-to-end latency and ii) deployment time.

Ahstract-5G stakeholders make every effort to efficiently handle the unprecedented services and traffic demand. Particularly, Telco operators aim to deploy a cost effective network services within their next generation mobile networks. By leveraging cloud-native architectures, the stringent 5G services requirements can be satisfied while reducing both CAPEX and OPEX. Concretely, the adoption of microservice software design enables the disaggregation of Telco applications into small independent cloud-native network functions. Theses microservices, deployed as containers, are lightweight and perform in an independent way. However, in spite of its various benefits, microservice architecture raises new challenges to deal with in the network function virtualization (NFV) ecosystem. Typically, the service function chaining (SFC) of cloud-native network functions becomes extremely complex and error-prone due to the high number of microservices. In this paper, we address the problem of 5G traffic steering for cloud-native SFC in microservice based NFV ecosystem. Specifically, we envision and deploy an SDNless SFC framework ensuring efficient traffic steering between cloud-native network functions. Besides, we propose an optimized network-aware load balancing algorithm capable of carrying efficiently the traffic while considering the underlying infrastructure network state. Based on robust experiments conducted in the deployed Kubernetes-based platform, the results show the efficiency of our strategy in terms of deployment time and network performance.

Harvesting of wildlife by humans is commonly known to impact target species’ demography, life history and behaviour. Yet in the context of invasive and pest species control, behavioural shifts have received very little attention. The introduced common myna, Acridotheres tristis, is undergoing intensive control efforts in some areas of its Australian distribution. In order to investigate whether myna populations respond to harvesting, we compared the behaviour of free-ranging common mynas in areas of high and low trapping pressure. Behavioural analyses revealed that mynas in high trapping risk areas stayed closer to refuges, tended to form smaller groups, and were overall less detectable. Behavioural differences between high and lowly trapped areas were not attributable to variation in population density. Overall, these results are consistent with the hypothesis that common mynas have the potential to adjust their behaviour in response to heightened anthropic risk in the environment. Behavioural shifts in invasive alien species could modify their ecological impact and may interfere not only with the effectiveness of control measures, but also with how their effectiveness is assessed. Future research should aim to isolate behavioural mechanisms underpinning compensatory responses to control so that any potential effects can be mitigated.

Social learning of novel threats coupled with adaptive generalization from learned to novel cues together provide the cognitive mechanisms by which adaptive avoidance of threats can spread rapidly both within and across generations. Whereas attention to effects of fishing and hunting on prey is increasing, nothing is known about how human predation can alter the behavior of invasive animals. Here, we examined whether common (Indian) mynas, Acridotheres tristis, one of the most widespread invasive birds in Australia and invasive to many other parts of the world, are learning to respond to anthropogenic predation. We analyzed behavior at an experimental food patch provisioned by 2 distinctly clothed persons both before and after mynas had observed one of the 2 persons seemingly capture conspecifics inside a trap placed at the food patch. After the demonstration, mynas landed in smaller numbers at the food patch and took longer to land. Further, mynas alarm called more when provisioned by the person who had been involved in trapping. Future work will determine whether narrow generalization gradients are a consistent feature of synanthropic species or whether they broaden as a function of human predation threat level as is predicted by the Predator Recognition Continuum Hypothesis. Practical implications for control are discussed. Can common mynas, one of the World's most invasive birds and target of much control effort, learn to avoid trapping? After watching mynas being captured by a person who had previously fed them, observer mynas alarm called specifically to that person. They also learned the place where trapping occurred and showed generalized changes in risk-awareness. Mynas show a remarkable capacity to learn socially, which explains why they are becoming more risk-averse in areas where they are trapped.

The capacity to behave innovatively facilitates adaptation to changing environmental conditions and accelerates speciation rates. Innovation tendencies show substantial variation both among and within species, but the sources of this variation remain poorly understood. There has been much debate on the role of cognition and significant amounts of empirical research on the influence of motivational and state-dependent processes, but the prediction that innovation might also be facilitated by motor processes has only recently begun to gain traction. Here, we measured innovative foraging in 7 common urban avian species under free-ranging conditions and explored the role of motor flexibility as well as several potential other predictors of innovation such as motivation and morphology. Species differed significantly in their tendency to forage innovatively, with a true corvid, the Australian raven, Corvus coronoides, outperforming all other species. Across species, motor flexibility was the strongest predictor of the capacity to forage innovatively. Our results extend previous work demonstrating the role of motor diversity in individual differences in the tendency to forage innovatively and provide the impetus for future research on links between motor and cognitive flexibility.

Macro-ecological comparisons have repeatedly demonstrated that the taxonomic distribution of foraging innovations coincides with the ability to adjust to novel and changing environments. We sought to obtain experimental support for the link between innovative foraging and opportunism by measuring the innovation abilities of two highly successful passerines on the east coast of Australia with very different success strategies. The ecological success of the introduced Indian myna, Acridotheres tristis, has been linked to its ability to occupy opportunistically an ecological niche that most natives cannot, whereas the native noisy miner, Manorina melanocephala, owes its success to its ability to aggressively outcompete other avian species. Indian mynas were significantly more neophobic than noisy miners. Yet, when tested on a range of innovative foraging tasks, Indian mynas consistently outperformed noisy miners. The ability to use the beak in a greater range of ways, and more flexibly, was highly repeatable in Indian mynas, and underpinned their superior problem-solving performance. We discuss the results in the light of potential methodological influences, but also the idea that necessity may facilitate innovation not only in less competitive individuals, as is documented in the literature, but also in species with less competitive lifestyles.

Foraging innovations are increasingly viewed as a key source of phenotypic plasticity and evolutionary change. Often thought to be associated with increased cognitive abilities, innovative foraging behaviour could potentially emerge as a simple consequence of being able to use a greater variety of motor actions in the foraging context. Here, we explored the role of motor diversity in the innovative problem-solving abilities of a highly successful ecological invader, the Indian myna, Sturnus tristis, using an extractive foraging task with multiple compartments. Consistent with findings from several other species, persistence predicted the latency to solve the first compartment. However, motor diversity was the strongest predictor of both solving latency of all further compartments and number of compartments solved. We suggest that motor diversity may facilitate innovation by increasing the ways in which objects can be handled, which in turn would allow for associative learning processes to enhance the expression of successful foraging behaviours.