Impacts of environmentally relevant concentrations of antibiotic cocktails on the skin microbiome of Eurasian carp (Cyprinus carpio).

Background: The skin surfaces of fish harbour diverse assemblages of microbes (microbiomes) that play critical roles in host health and disruption of these microbiomes can lead to disease conditions. Antibiotics, widely used in medicine for human and animal health treatments, are increasingly found in waterways and this is a growing concern due to their potential to alter the balance of microbial ecosystems and drive antimicrobial resistance (AMR). The effects of antibiotics on skin microbiomes in fish, however, have been little explored.

Working for the environment: farmer attitudes towards sustainable farming actions in rural Wales, UK.

Recognition of land management impacts on water quality and flooding, and climate change-induced increases in storm intensity and flood risk, have led to interest in farmer provision of ecosystem services alongside food production. However, pathways for practical design and funding of agroecological interventions are less well understood. Effective design and implementation of sustainable farming initiatives have been linked to human-centred aspects including stakeholder engagement and provision of social and economic co-benefits.

Toxicity of the water-soluble polymer PVP is dependent on molecular weight and feed concentration for a freshwater model species.

Polyvinylpyrrolidone (PVP) is a synthetic water-soluble polymer (WSP) that does not readily biodegrade and has been detected in rivers in the mg L range. Whilst previous studies have highlighted sublethal impacts of this chemical on freshwater species, cause of this toxicity remains unclear. The current study investigates how polymer molecular weight impacts the freshwater model species, Daphnia magna.

Light and electron microscopy of the pharynx and gastrodermis of the monogenean gill parasite Macrogyrodactylus clarii from the catfish Clarias gariepinus (Burchell, 1822).

The functional morphology of the digestive system in monogeneans is important in understanding feeding behaviour, dietary intake, and metabolic activity of the caecal epithelium. The present study used light and transmission electron microscopy to reveal detailed structure of the pharynx and gastrodermis of the viviparous gill monogenean Macrogyrodactylus clarii to compare with the congeneric skin monogenean Macogyrodactylus congolensis and other gyrodactylids. The basic components of the pharynx and gastrodermis of M.

Epidemiological and genotypic assessment of cystic echinococcosis in ruminant populations of Northern Punjab, Pakistan: a neglected zoonotic disease.

Echinococcus granulosus is a zoonotic dog parasite, which causes cystic echinococcosis in humans and animals, adversely affecting health and food production. The resultant socio-economic impacts in lower-middle-income countries and the paucity of epidemiology data prompted the World Health Organization to classify cystic echinococcosis as a neglected tropical disease. Between November 2019 and December 2020, the prevalence of cystic echinococcosis was assessed from 3600 post-slaughter livestock (1142 sheep, 1258 goats and 1200 buffalo) from three districts, Narowal, Sheikhupura and Sialkot, in Northern Punjab, Pakistan.

Analysis of bamboo fibres and their associated dye on a freshwater fish host-parasite system.

With the growth of the fashion and textile industries into the twenty-first century, associated pollution has become pervasive. Fibre-based microplastics are the most common types of plastics recovered from aquatic ecosystems encouraging the move towards organic fibre usage. Often marketed as biodegradable and 'environmentally friendly', organic textile fibres are seen as less harmful, but their impacts are understudied.

Gyrodactylus in the spotlight: how exposure to light impacts disease and the feeding behavior of the freshwater tropical guppy (Poecilia reticulata).

Artificial light at night (ALAN) negatively impacts organisms in many ways, from their feeding behaviors to their response and ability to deal with disease. Our knowledge of ALAN is focused on hosts, but we must also consider their parasites, which constitute half of all described animal species. Here, we assessed the impact of light exposure on a model host-parasite system (Poecilia reticulata and the ectoparasitic monogenean Gyrodactylus turnbulli).

Detection of polyvinylpyrrolidone in Daphnia magna: Development of a refractive index quantification method for water-soluble polymers in aquatic organisms.

The water-soluble polymer polyvinylpyrrolidone (PVP) is an established ingredient in pharmaceutical and personal care product (PPCP) formulations. Due to its high usage and lack of biodegradability, it has been detected up to 7.0 mg L in wastewater and 0.

Restless nights when sick: ectoparasite infections alter rest-activity cycles of diurnal fish hosts.

Circadian rhythms are timekeeping mechanisms responsible for an array of biological processes. Disruption of such cycles can detrimentally affect animal health. Circadian rhythms are critical in the co-evolution of host–parasite systems, as synchronization of parasite rhythms to the host can influence infection dynamics and transmission potential.

Influence of host phylogeny and water physicochemistry on microbial assemblages of the fish skin microbiome.

The skin of fish contains a diverse microbiota that has symbiotic functions with the host, facilitating pathogen exclusion, immune system priming, and nutrient degradation. The composition of fish skin microbiomes varies across species and in response to a variety of stressors, however, there has been no systematic analysis across these studies to evaluate how these factors shape fish skin microbiomes. Here, we examined 1922 fish skin microbiomes from 36 studies that included 98 species and nine rearing conditions to investigate associations between fish skin microbiome, fish species, and water physiochemical factors.

Colour as a behavioural guide for fish near hydrokinetic turbines.

Hydropower is a traditional and widespread form of renewable energy and vertical axis turbines are an emerging technology suitable for low to medium velocity water bodies such as rivers. Such devices can provide renewable power to remote communities but may also contribute to fragmenting already poorly connected riverine habitats and the impact could be particularly pronounced for migratory diadromous aquatic species such as salmonids by limiting their ability to pass the turbines. Optimising the design of such turbines is therefore essential to mitigate their impact on aquatic fauna.

The impacts of synthetic and cellulose-based fibres and their associated dyes on fish hosts and parasite health.

Plastic pollution is now a ubiquitous feature of freshwater systems and the majority of this is fibrous. Here, we test the effects of plastic and cellulose-based fibres (polyester, cotton, and bamboo from commercial clothing) on fish host-parasite interactions using a freshwater fish host-parasite model system (guppy Poecilia reticulata-Gyrodactylus turnbulli). For uninfected fish, polyester exposure was associated with significantly higher mortality rates compared with the other two fibre types.

A class of their own? Water-soluble polymer pollution impacting a freshwater host-pathogen system.

While the inclusion of synthetic polymers such as primary microplastics within personal care products have been widely restricted under EU/UK Law, water-soluble polymers (WSPs) have so far slipped the net of global chemical regulation despite evidence that these could be polluting wastewater effluents at concentrations greatly exceeding those of microplastics. Polyvinyl alcohol (PVA) and polyvinylpyrrolidone (PVP) represent WSPs with common industry and household uses, down-the-drain disposal and a direct route to wastewater treatment plants, conveying high risk of environmental leaching into freshwater ecosystems. The current study is the first investigating the impacts of predicted environmental concentrations of these WSPs on life-history traits of two freshwater species also constituting a disease model (fish - Poecilia reticulata and parasite - Gyrodactylus turnbulli).

The occurrence and zoonotic potential of Cryptosporidium species in freshwater biota.

Background: Protozoan pathogens from the genus Cryptosporidium cause the diarrhoeal disease cryptosporidiosis in humans and animals globally. Freshwater biota could act as potential reservoirs or zoonotic sources of Cryptosporidium infections for livestock and people, but Cryptosporidium occurrence in aquatic biota is largely unexplored. The aim of this study was to investigate the occurrence of Cryptosporidium in a range of freshwater organisms in upland rivers across England and Wales.

The presence of territorial damselfish predicts choosy client species richness at cleaning stations.

Mutualisms are driven by partners deciding to interact with one another to gain specific services or rewards. As predicted by biological market theory, partners should be selected based on the likelihood, quality, reward level, and or services each partner can offer. Third-party species that are not directly involved in the interaction, however, may indirectly affect the occurrence and or quality of the services provided, thereby affecting which partners are selected or avoided.

Microplastic exposure and consumption increases susceptibility to gyrodactylosis and host mortality for a freshwater fish.

Microplastics have been found in all surveyed ecosystems and in the diet of multiple species. Detrimental health impacts of microplastic consumption include reduced growth and fecundity, metabolic stress and immune alterations for both invertebrates and vertebrates. Limited information exists, however, on how disease resistance may be affected by microplastic exposure and consumption.

IEg67 kDa Bovine Hydatid Cyst Antigen: A Candidate for Developing Sero-Diagnostic Assays for Cystic Echinococcosis, a Disease of One Health Importance.

Cystic echinococcosis (hydatidosis) is a world-wide zoonotic disease of mainly humans, livestock and dogs, caused by . The disease can negatively impact food production and animal welfare and causes socio-economic hardship. Here, we aimed to identify the local bovine hydatid cyst fluid (BHCF) antigen for developing a sero-diagnostic assay to be used for the pre-slaughter screening of food animals.

The microscopic five of the big five: Managing zoonotic diseases within and beyond African wildlife protected areas.

African protected areas strive to conserve the continent's great biodiversity with a targeted focus on the flagship 'Big Five' megafauna. Though often not considered, this biodiversity protection also extends to the lesser-known microbes and parasites that are maintained in these diverse ecosystems, often in a silent and endemically stable state. Climate and anthropogenic change, and associated diversity loss, however, are altering these dynamics leading to shifts in ecological interactions and pathogen spill over into new niches and hosts.

Differential effects of two prevalent environmental pollutants on host-pathogen dynamics.

Chemical pollutants are a major factor implicated in freshwater habitat degradation and species loss. Microplastics and glyphosate-based herbicides are prevalent pollutants with known detrimental effects on animal welfare but our understanding of their impacts on infection dynamics are limited. Within freshwater vertebrates, glyphosate formulations reduce fish tolerance to infections, but the effects of microplastic consumption on disease tolerance have thus far not been assessed.

Circadian dynamics of the teleost skin immune-microbiome interface.

Background: Circadian rhythms of host immune activity and their microbiomes are likely pivotal to health and disease resistance. The integration of chronotherapeutic approaches to disease mitigation in managed animals, however, is yet to be realised. In aquaculture, light manipulation is commonly used to enhance growth and control reproduction but may have unknown negative consequences for animal health.

Longitudinal sampling of external mucosae in farmed European seabass reveals the impact of water temperature on bacterial dynamics.

Fish microbiota are intrinsically linked to health and fitness, but they are highly variable and influenced by both biotic and abiotic factors. Water temperature particularly limits bacterial adhesion and growth, impacting microbial diversity and bacterial infections on the skin and gills. Aquaculture is heavily affected by infectious diseases, especially in warmer months, and industry practices often promote stress and microbial dysbiosis, leading to an increased abundance of potentially pathogenic bacteria.

Shining a light on parasite behaviour: daily patterns of fish lice.

Parasites display a wide range of behaviours that are frequently overlooked in favour of host responses. Understanding these behaviours can improve parasite control through a more precise application or development of new behaviour-based strategies. In aquaculture fish lice are an ongoing problem, infections reduce fishery production and control options are limited.