Several animal species, including ferrets, hamsters, monkeys, and raccoon dogs, have been shown to be susceptible to experimental infection by the human severe acute respiratory syndrome ...coronaviruses, such as SARS-CoV and SARS-CoV-2, which were responsible for the 2003 SARS outbreak and the 2019 coronavirus disease (COVID-19) pandemic, respectively. Emerging studies have shown that SARS-CoV-2 natural infection of pet dogs and cats is also possible, but its prevalence is not fully understood. Experimentally, it has been demonstrated that SARS-CoV-2 replicates more efficiently in cats than in dogs and that cats can transmit the virus through aerosols. With approximately 470 million pet dogs and 370 million pet cats cohabitating with their human owners worldwide, the finding of natural SARS-CoV-2 infection in these household pets has important implications for potential zoonotic transmission events during the COVID-19 pandemic as well as future SARS-related outbreaks. Here, we describe some of the ongoing worldwide surveillance efforts to assess the prevalence of SARS-CoV-2 exposure in companion, captive, wild, and farmed animals, as well as provide some perspectives on these efforts including the intra- and inter-species coronavirus transmissions, evolution, and their implications on the human-animal interface along with public health. Some ongoing efforts to develop and implement a new COVID-19 vaccine for animals are also discussed. Surveillance initiatives to track SARS-CoV-2 exposures in animals are necessary to accurately determine their impact on veterinary and human health, as well as define potential reservoir sources of the virus and its evolutionary and transmission dynamics.
Lassa fever (LF) is a deadly viral hemorrhagic disease that is endemic to West Africa. The causative agent of LF is Lassa virus (LASV), which causes approximately 300,000 infections and 5,000 deaths ...annually. There are currently no approved therapeutics or FDA-approved vaccines against LASV. The high genetic variability between LASV strains and immune evasion mediated by the virus complicate the development of effective therapeutics and vaccines. Here, we aim to provide a comprehensive review of the basic biology of LASV and its mechanisms of disease pathogenesis and virulence in various animal models, as well as an update on prospective vaccines, therapeutics, and diagnostics for LF. Until effective vaccines and/or therapeutics are available for use to prevent or treat LF, a better level of understanding of the basic biology of LASV, its natural genetic variations and immune evasion mechanisms as potential pathogenicity factors, and of the rodent reservoir-vector populations and their geographical distributions, is necessary for the development of accurate diagnostics and effective therapeutics and vaccines against this deadly human viral pathogen.
Management areas are used in marine spatial planning to conserve biodiversity of marine ecosystems and to protect fish from fishing pressure. To evaluate the effectiveness of these protected areas, ...observational techniques are used to determine densities, sizes, biomass, habitat types and distribution of fish species in and around management areas. Two types of observational techniques are used in spatial monitoring: (1) fishery-independent techniques, which include underwater visual census (UVC), underwater video, remote sensing, acoustics, and experimental catch and effort data; and (2) fishery-dependent techniques, which include catch, effort and catch per unit effort data from commercial and recreational fisheries. This review summarises the applications, advantages, disadvantages and biases of each of these observational categories and highlights emerging technologies. The main finding from this review was that a combination of observational techniques, rather than a single method, was the most effective approach to marine spatial monitoring. For example, a combination of hydroacoustics for habitat mapping and UVC or video for fish surveys was one of the most cost-effective and efficient means of obtaining fish-habitat linkages and fish assemblage data. There are also emerging technologies that could increase the precision and efficiency of monitoring surveys. There is a need for continued development of non-intrusive technology for marine monitoring studies.
Abstract Fish species with high mortality during early life may maximize fitness using adaptive strategies to time hatching to match favorable environmental conditions (match/mismatch) or extending ...spawning/hatching to disperse risk (bet-hedging). We examined support for these strategies in a collapsed forage fish, capelin (Mallotus villosus), in coastal Newfoundland (2018–2021). Capelin shift from spawning at warm, intertidal to cool, subtidal (15–40 m) habitats in warmer years, with unknown recruitment consequences. We hypothesized that match/mismatch (specifically, Coastal Water Mass Replacement Hypothesis) would be supported if densities of recently hatched larvae showed pulses that overlapped with high prey and low predator densities. Generalized additive models revealed that larval densities increased with zooplankton prey biomass, but were not influenced by predator biomass or temperature, contrasting with pre-collapse studies and providing equivocal support for match/mismatch. Protracted larval emergence and previously documented high variability in larval traits supported a bet-hedging strategy. Larval condition (i.e. length, yolk-sac diameter) did not differ between habitats but varied among years, where the highest proportion of larvae in poor condition was from the intertidal site in the warmest year (2018). Findings suggest that spawning habitat shifts may have limited impact on stock recovery relative to year-specific environmental conditions that influence larval condition.
Abstract
Spawning timing in fish is generally cyclical in temperate regions in order to increase the probability of matching larval occurrence with ideal environmental conditions. The capelin stock ...in Northwest Atlantic Fisheries Organization Divisions 2J3KL collapsed in 1990–1991 and has not recovered. This collapse was concomitant with collapses in groundfish stocks and cold oceanographic conditions. Using citizen science data, newspaper archives, grey and primary literature, and monitoring data, a century of capelin beach spawning times were compiled. Capelin beach spawning has been persistently 3 weeks later since the stock collapse. To identify potential predictors of capelin spawning timing, an exploratory analysis was conducted using environmental and biological variables and a period factor that categorized a year as either pre-collapse (1990 and earlier) or post-collapse (post-1990) in a step-wise multiple regression model. Spawning timing was predicted to be delayed in the post-collapse period when there were negative anomalies in the Newfoundland and Labrador Climate Index and summer (June–August) North Atlantic Oscillation, and when there was a decrease in mean length of the spawning population. The production of weak year-classes is predicted when spawning is delayed, suggesting that late spawning is severely inhibiting the recovery of the stock.
Despite 100 years of research testing the link between prey availability during the larval stage and year-class strength, field-based evidence for Hjort's "critical period" hypothesis remains ...equivocal. Here, we argue that a minority of past studies have relied on sufficient taxonomical knowledge of larval fish prey preference to reveal the potential effects of variability in zooplankton prey production on larval vital rates and year-class strength. In contrast to the juvenile and adult stages, larval fish diet and prey field are often poorly resolved, resulting in the inclusion of zooplankton taxa that do not actually contribute to the diet as part of the prey field considered by fisheries scientists. Recent studies have demonstrated that when accounting for prey selectivity, the expected positive relationships between preferred prey availability and larval feeding success, growth and survival are revealed. We strongly recommend that laboratories conducting research on larval fish trophodynamics take prey selectivity into account and acquire the necessary taxonomic expertise for providing valid assessments of the influence of prey availability on larval vital rates. We make the prediction that the proportion of studies supporting the existence of a "critical period" will increase proportionally to the progress of knowledge on prey preference during the early larval stage.
The sixteenth century saw an unprecedented growth in the number of educated physicians practicing in German cities. Concentrating on Nuremberg,A New Order of Medicine follows the intertwined careers ...of municipal physicians as they encountered the challenges of the Reformation city for the first time. Although conservative in their professed Galenism, these men were eclectic in their practices, which ranged from book collecting to botany to subversive anatomical experimentations. Their interests and ambitions lead to local controversy. Over a twenty-year campaign, apothecaries were wrested from their place at the forefront of medical practice, no longer able to innovate remedies, while physicians, recent arrivals in the city, established themselves as the leading authorities. Examining archives, manuscript records, printed texts, and material and visual sources, and considering a wide range of diseases, Hannah Murphy offers the first systematic interpretation of the growth of elite medical "practice," its relationship to Galenic theory, and the emergence of medical order in the contested world of the German city.
Atlantic herring (Clupea harengus; hereafter herring) is a forage fish that transfers energy from lower to higher trophic levels and sustains high-volume fisheries in the North Atlantic. This study ...aims to improve our understanding of the ecology of Newfoundland herring and its vulnerability to climate change by identifying key prey items and describing adult herring feeding strategies. We compared plankton assemblages to stomach content and stable isotope analyses from herring collected in Trinity Bay, Newfoundland, in late summer and autumn 2017–2019. Six distinct zooplankton communities were identified across all years, with a shift in community structure in September 2018. This shift coincided with a change from fresher, warmer waters (12–17 °C) to more saline, cooler waters (10.5 °C). The most frequently consumed prey items were amphipods (Themisto spp.) and calanoid copepods (primarily Calanus and Temora spp.). Fish eggs, larvae, and juveniles, primarily identified as capelin, were observed in stomach contents in all years. Fish contributed most to diets in 2017, which corresponded with the peak year for larval densities in Trinity Bay, suggesting that piscivory may increase at higher larval densities. Herring were opportunistic feeders, although some individuals exhibited selective feeding on copepods, amphipods, euphausiids, and the early life stages of fishes. Stable isotope analyses supported the finding that herring piscivory is prevalent in eastern Newfoundland. Given its adaptive feeding strategy and wide range of consumed prey, we conclude that adult Newfoundland herring is resilient to bottom-up changes observed in the environment.
Lassa fever (LF) is a deadly viral hemorrhagic fever disease that is endemic in several countries in West Africa. It is caused by Lassa virus (LASV), which has been estimated to be responsible for ...approximately 300,000 infections and 5000 deaths annually. LASV is a highly pathogenic human pathogen without effective therapeutics or FDA-approved vaccines. Here, we aim to provide a literature review of the current understanding of the basic mechanism of immune responses to LASV infection in animal models and patients, as well as to several of its candidate vaccines.
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