The Effect of Stress on the Skin Welfare of Lumpfish ( Linnaeus, 1758) Broodstock.

The aim of this study was to build on the work already conducted in optimising lumpfish broodstock temperature, photoperiod and nutrition by providing vital information on the stress relationship between mucosal barrier functions and the sexual development of lumpfish broodstock. From a population of approx. 300 fish of 1587 g (SEM ± 704 g), a sub-population of 20 fish was injected with 30 mg/kg fish cortisol implants on 5 January 2018.

Mucosal epithelial homeostasis: Reference intervals for skin, gill lamellae and filament for Atlantic salmon and other fish species.

Mucosal barriers are gatekeepers of health and exhibit homeostatic variation in relation to habitat and disease. Mucosal Mapping technology provides an in-depth examination of the dynamic mucous cells (MCs) in fish mucosal barriers on tangential sections, about 90° from the view of traditional histology. The method was originally developed and standardized in academia prior to the establishment of QuantiDoc AS to apply mucosal mapping, now trademarked as Veribarr™ for the analysis of skin, gills and gastrointestinal tracts.

Mucosal immune and stress responses of -infected Atlantic salmon () treated with peracetic acid shed light on the host-parasite-oxidant interactions.

Treatment development for parasitic infestation is often limited to disease resolution as an endpoint response, and physiological and immunological consequences are not thoroughly considered. Here, we report the impact of exposing Atlantic salmon affected with amoebic gill disease (AGD) to peracetic acid (PAA), an oxidative chemotherapeutic. AGD-affected fish were treated with PAA either by exposing them to 5 ppm for 30 min or 10 ppm for 15 min.

Multiomics Provide Insights into the Key Molecules and Pathways Involved in the Physiological Adaptation of Atlantic Salmon () to Chemotherapeutic-Induced Oxidative Stress.

Although chemotherapeutics are used to treat infections in farmed fish, knowledge on how they alter host physiology is limited. Here, we elucidated the physiological consequences of repeated exposure to the potent oxidative chemotherapeutic peracetic acid (PAA) in Atlantic salmon () smolts. Fish were exposed to the oxidant for 15 (short exposure) or 30 (long exposure) minutes every 15 days over 45 days.

Nutrient Digestibility, Growth, Mucosal Barrier Status, and Activity of Leucocytes From Head Kidney of Atlantic Salmon Fed Marine- or Plant-Derived Protein and Lipid Sources.

Nutrient digestibility, growth, and mucosal barrier status of fish skin, gills, and distal intestine were studied in Atlantic salmon fed feeds based on marine or plant-derived ingredients. The barrier status was assessed by considering the expression of four mucin genes, five genes that encode antimicrobial proteins, distal intestine micromorphology, and design-based stereology of the midgut epithelium. In addition, the head kidney leukocytes were examined using flow cytometry; to understand the differences in their counts and function.

Histological mucous cell quantification and mucosal mapping reveal different aspects of mucous cell responses in gills and skin of shorthorn sculpins (Myoxocephalus scorpius).

In teleosts, the mucosal epithelial barriers represent the first line of defence against environmental challenges such as pathogens and environmental contaminants. Mucous cells (MCs) are specialised cells providing this protection through mucus production. Therefore, a better understanding of various MC quantification methods is critical to interpret MC responses.

Atlantic salmon (Salmo salar) mounts systemic and mucosal stress responses to peracetic acid.

Peracetic acid (PAA), a strong organic peroxide, is considered a relatively sustainable disinfectant in aquaculture because of its broad effectivity against many pathogens at low concentrations and because it degrades spontaneously to harmless residues. The impacts of PAA on fish health must be determined before its use as either a routine disinfectant or chemotherapeutant. Here we investigated the systemic and mucosal stress responses of Atlantic salmon (Salmo salar) to PAA.

Mucous cell responses to contaminants and parasites in shorthorn sculpins (Myoxocephalus scorpius) from a former lead‑zinc mine in West Greenland.

Previous studies of sculpins from the former lead (Pb) - zinc (Zn) mine near Maarmorilik, West Greenland, have shown that these fish are affected by heavy metal exposure from the mine. In this study, we applied mucosal mapping (a stereological method for mucosal quantification in fish) to uncover interactions between the host, parasites and heavy metal exposure (Pb and Zn) in shorthorn sculpins from the Maarmorilik mining site at a gradient of 3 stations. Skin and gill mucosal epithelia of shorthorn sculpins were significantly affected and reflected the exposure to environmental heavy metals and parasites.

Fucosterol Causes Small Changes in Lipid Storage and Brassicasterol Affects some Markers of Lipid Metabolism in Atlantic Salmon Hepatocytes.

Several feeding trials with Atlantic salmon fed naturally high phytosterol concentrations due to dietary rapeseed oil inclusion have shown changes in lipid metabolism and increased hepatic lipid storage in the fish. An in vitro trial with Atlantic salmon hepatocytes was, therefore, performed to study the possible direct effects of phytosterols on lipid storage and metabolism. The isolated hepatocytes were exposed to seven different sterol treatments and gene expression, as well as lipid accumulation by Oil Red O dyeing, was assessed.

Dietary Mannan Oligosaccharides: Counteracting the Side Effects of Soybean Meal Oil Inclusion on European Sea Bass (Dicentrarchus labrax) Gut Health and Skin Mucosa Mucus Production?

The main objective of this study was to assess the effects of 4 g kg(-1) dietary mannan oligosaccharides (MOS) inclusion in soybean oil (SBO)- and fish oil (FO)-based diets on the gut health and skin mucosa mucus production of European sea bass juveniles after 8 weeks of feeding. Dietary MOS, regardless of the oil source, promoted growth. The intestinal somatic index was not affected, however dietary SBO reduced the intestinal fold length, while dietary MOS increased it.

The effect of stunning methods and season on muscle texture hardness in Atlantic salmon (Salmo salar L.).

Unlabelled: Commercially collected records of Atlantic salmon (Salmo salar L.) muscle texture hardness were used to evaluate the effect of slaughter procedures and seasonality on texture quality. A database collected by Marine Harvest® contained flesh hardness records of Atlantic salmon slaughtered at processing plants in Norway from summer 2010 to summer 2011.

Trophic structure and community stability in an overfished ecosystem.

Since the collapse of the pelagic fisheries off southwest Africa in the late 1960s, jellyfish biomass has increased and the structure of the Benguelan fish community has shifted, making the bearded goby (Sufflogobius bibarbatus) the new predominant prey species. Despite increased predation pressure and a harsh environment, the gobies are thriving. Here we show that physiological adaptations and antipredator and foraging behaviors underpin the success of these fish.

Post-embryonic remodelling of neurocranial elements: a comparative study of normal versus abnormal eye migration in a flatfish, the Atlantic halibut.

The process of eye migration in bilaterally symmetrical flatfish larvae starts with asymmetrical growth of the dorsomedial parts of the ethmoid plate together with the frontal bones, structures initially found in a symmetrical position between the eyes. The movement of these structures in the future ocular direction exerts a stretch on the fibroblasts in the connective tissue found between the moving structures and the eye that is to migrate. Secondarily, a dense cell population of fibroblasts ventral to the eye starts to proliferate, possibly cued by the pulling forces exerted by the eye.

Twisted story of eye migration in flatfish.

Early molecular markers for flatfish metamorphosis and eye migration must be linked to the ethmoid region, the earliest part of the flatfish cranium to change, as well as chondral and dermal ossification processes. Serial sections, morphological landmarks, and stereology were used to determine where and when the remodeling of tissues and asymmetry occurs in the head region of metamorphosing Atlantic halibut, Hippoglossus hippoglossus. Not all parts of the head remodel or migrate, and those that do may be asynchronous.