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Background: Studies evaluating the potential impact of photographer experience or the number of images evaluated using the "store-and-forward" method of telecytology are not reported., Objectives: This study aimed to determine the diagnostic sensitivity (Se) and specificity (Sp) of static telecytology when images were taken by experienced and inexperienced cytologists and when the number of images taken varied. Clinical agreement between the diagnoses was compared., Methods: Fifty archived cytology cases were randomly chosen. A board-certified clinical pathologist and a recent veterinary graduate took five images of each case. A third pathologist made a preliminary diagnosis after reviewing two images, and a final diagnosis after reviewing all images. The gold standard for comparison was the glass slide cytologic diagnosis., Results: Se and Sp were higher for the experienced cytologist and the evaluation of more images, but differences were not statistically significant. Clinical agreement between the image and glass slide diagnoses was significantly higher when images were taken by an experienced rather than inexperienced cytologist after the evaluation of two (P = .007) and five images (P = .008). The telecytology diagnoses agreed with the gold standard diagnoses more frequently after evaluation of five images rather than two when images were captured by both the experienced (P < .001) and inexperienced cytologist (P < .001)., Conclusions: There is more clinical agreement when the photographer has more cytology experience and when more images are provided for interpretation., (© 2019 American Society for Veterinary Clinical Pathology.)

Currently, cleaner fish are one of the most widely used sea lice control strategies in Atlantic salmon aquaculture. Two species are currently being farmed in North Atlantic countries, ballan wrasse ( Labrus bergylta ) and lumpfish ( Cyclopterus lumpus ), and the sector in most countries is rapidly expanding towards self-sufficiency. The species are very different both in terms of their biology and life histories and, consequently, production and husbandry methods must be tailored to each species. There are numerous health challenges currently experienced in both species, with bacterial and parasitic diseases being the most prevalent, and cohabitation with salmon may increase the risk of disease. Good husbandry and routine health monitoring are essential, although treatment is often required when disease outbreaks occur. Ballan wrasse and lumpfish are both proven to be effective salmon delousers, although delousing efficacy can be variable in farmed fish; the provision of suitable habitat and acclimation to net-pen conditions may encourage natural behaviours, including delousing, and the use of operational welfare indicators can highlight potential welfare issues. Cleaner fish research is progressing rapidly, although much of the basic knowledge regarding the species' biology remains unknown. The simultaneous domestication of two new marine aquaculture species is a significant challenge demanding sustained effort and funding over a prolonged period of time. Research must focus on enhancing the robustness of the farmed stocks and increasing hatchery outputs to meet the urgent demands from the salmon sector and protect wild stocks from overfishing., Competing Interests: Competing interests: None declared., (© British Veterinary Association (unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.)

Parasites have a major impact on global finfish and shellfish aquaculture, having significant effects on farm production, sustainability and economic viability. Parasite infections and impacts can, according to pathogen and context, be considered to be either unpredictable/sporadic or predictable/regular. Although both types of infection may result in the loss of stock and incur costs associated with the control and management of infection, predictable infections can also lead to costs associated with prophylaxis and related activities. The estimation of the economic cost of a parasite event is frequently complicated by the complex interplay of numerous factors associated with a specific incident, which may range from direct production losses to downstream socio-economic impacts on livelihoods and satellite industries associated with the primary producer. In this study, we examine the world's major marine and brackish water aquaculture production industries and provide estimates of the potential economic costs attributable to a range of key parasite pathogens using 498 specific events for the purposes of illustration and estimation of costs. This study provides a baseline resource for risk assessment and the development of more robust biosecurity practices, which can in turn help mitigate against and/or minimise the potential impacts of parasite-mediated disease in aquaculture.

The life cycle of the parasitic copepod Lernaeocera branchialis involves 2 hosts, typically a pleuronectiform host upon which development of larvae and mating of adults occurs and a subsequent gadoid host, upon which the adult female feeds and reproduces. Both the copepodid and adult female stages must therefore locate and identify a suitable host to continue the life cycle. Several mechanisms are potentially involved in locating a host and ensuring its suitability for infection. These may include mechano-reception to detect host movement and chemo-reception to recognize host-associated chemical cues, or kairomones. The aim of this study was to identify the role of kairomones in host location by adult L. branchialis, by analysing their behaviour in response to fish-derived chemicals. Experiments demonstrated that water conditioned by immersion of whiting, Merlangius merlangus, elicited host-seeking behaviour in L. branchialis, whereas cod- (Gadus morhua) conditioned water did not. Lernaeocera branchialis are considered a genetically homogeneous population infecting a range of gadoids. However, their differential response to whiting- and cod-derived chemicals in this study suggests that either there are genetically determined subspecies of L. branchialis or there is some form of environmental pre-conditioning that allows the parasite to preferentially recognize the host species from which it originated.

Background: The high transmission potential of species belonging to the monogenean parasite genus Gyrodactylus, coupled with their high fecundity, allows them to rapidly colonise new hosts and to increase in number. One gyrodactylid, Gyrodactylus salaris Malmberg, 1957, has been responsible for devastation of Altantic salmon (Salmo salar L.) populations in a number of Norwegian rivers. Current methods of eradicating G. salaris from river systems centre around the use of non-specific biocides, such as rotenone and aluminium sulphate.Although transmission routes in gyrodactylids have been studied extensively, the behaviour of individual parasites has received little attention. Specimens of Gyrodactylus gasterostei Gläser, 1974 and G. arcuatus Bychowsky, 1933, were collected from the skin of their host, the three-spined stickleback (Gasterosteus aculeatus L.), and permitted to attach to the substrate. The movements of individual parasites were recorded and analysed., Results: The behaviour patterns of the two species were similar and parasites were more active in red light and darkness than in white light. Four octopaminergic compounds were tested and all four inhibited the movements of parasites. Treatment ultimately led to death at low concentrations (0.2 μM), although prolonged exposure was necessary in some instances., Conclusions: Octopaminergic compounds may affect the parasite's ability to locate and remain on its host and these or related compounds might provide alternative or supplementary treatments for the control of G. salaris infections. With more research there is potential for use of octopaminergic compounds, which have minimal effects on the host or its environment, as parasite-specific treatments against G. salaris infections.

This review concerns the parasitic marine copepod Lernaeocera branchialis (L., 1767) and provides an overview of current knowledge concerning its biology and host-parasite interactions. The large size and distinctive appearance of the metamorphosed adult female stage, coupled with the wide exploitation and commercial importance of its final gadoid hosts, means that this species has long been recognised in the scientific literature. The fact that the Atlantic cod, Gadus morhua L., is one of its key host species, and has itself had a major impact on the social and economic development of many countries bordering the North Atlantic for more than 10 centuries is also a factor in its widespread recognition. L. branchialis is recognised as a pathogen that could have major effects on the aquaculture industry and with gadoid (especially cod) farming expanding in several North Atlantic countries, there is considerable potential for this parasite to become a serious problem for commercial mariculture. The main subject areas covered are the parasite's taxonomy; the life history of the parasite including its life cycle, reproduction and host associations; parasite physiology; parasite seasonality and distribution; and the pathogenic effects of the parasite on its host.

HCFC-141b is one of the chemicals being considered as a replacement for CFC 11 in solvent and foam-blowing applications. Teratology studies were conducted in both rats and rabbits and a two-generation reproduction inhalation toxicity study was conducted in rats. The pregnant rabbits were exposed to levels of 0 (control), 1400, 4200 and 12,600 ppm HCFC-141b from day 7 to day 19 of gestation (6 hr/day). There was no evidence of developmental or teratogenic effects on the foetuses. The pregnant rats in the teratology study were exposed to levels of 0 (control), 3200, 8000 and 20,000 ppm from days 6 to 15 of gestation (6 hr/day). In the 20,000 ppm exposure group, there was an increase in implantation losses; furthermore, in this group, foetal weights tended to be lower than controls. As with the rabbits, there was no evidence of a teratogenic effect. The reproduction study was conducted at exposure levels of 0, 2000, 8000 and 20,000 ppm, 7 days/wk starting approximately 10 wk before the first pairing. Adult rats exposed at 20,000 ppm (and, to a lesser extent, those exposed to 8000 ppm) showed increases in water intake, slight increases in food consumption, and decreases in body weight. Following the mating of the F0 parents, there were fewer litters in the 20,000 ppm exposure level group than in controls. When these parents were then paired with different partners, again, the number of litters was lower in the 20,000 ppm group, although most of the animals that did not produce litters the first time mated successfully the second time. When the F1 animals were mated to produce the second generation, the number of litters was comparable for all groups. In the second F0 mating and the F1 mating, the number of pups per litter was lower at 20,000 ppm; although birth weights were comparable, body weight gain tended to be slower in the high-level exposure group. Survival was good in all groups. At 8000 ppm no significant effects were observed in the pups and only minimal signs in the adults. The 2000 ppm exposure level represented a clear no-observed-effect level for all indices.