Development, growth, and survival data derived from laboratory experiments are provided for Lepeophtheirus salmonis , a common ectoparasite of wild sea-farmed salmonids. The mean development time eggs was 419·1 hours (17·5 days) at 5°C, 207·1 (8·6 10°C, 130·8 (5·5 15°C. Development the first nauplius to infectious copepodid stage took 222·3 (9·3 87·4 (3·6 44·8 (1·9 egg adult male 40 days, female 52 days 10°C. No occurred 10‰ salinity. At 15‰ developed but failed produce active nauplii....

Aeromonas salmonicida subsp. is a Gram-negative bacterium that the causative agent of furunculosis, bacterial septicaemia salmonid fish. While other species are opportunistic pathogens or found in commensal symbiotic relationships with animal hosts, A. causes disease healthy The genome sequence was determined to provide better understanding virulence factors used by this pathogen infect nucleotide sequences A449 chromosome and two large plasmids characterized. 4,702,402 bp encodes 4388...

Lepeophtheirus salmonis (Copepoda: Caligoida) is an economically important marine ectoparasite of wild and pen-reared salmonids. The morphology its developmental stages described compared with that other species Caligus. development L. very similar to reported for species. appendages generally attain the adult condition sexes become distinguishable later in than Caligus At all except nauplius, can be distinguished from co-occurring clemensi.

Copepods outnumber every other multicellular animal group. They are critical components of the world's freshwater and marine ecosystems, sensitive indicators local global climate change, key ecosystem service providers, parasites predators economically important aquatic animals potential vectors waterborne disease. sustain world fisheries that nourish support human populations. Although genomic tools have transformed many areas biological biomedical research, their power to elucidate aspects...

Heart and skeletal muscle inflammation (HSMI) is a significant often fatal disease of cultured Atlantic salmon in Norway. The consistent presence Piscine orthoreovirus (PRV) HSMI diseased fish along with the correlation viral load antigen development lesions has supported supposition that PRV etiologic agent this condition; yet absence an vitro culture system to demonstrate causation widespread prevalence virus continues obfuscate etiological role regard HSMI. In study, we explore...

The recently described type III secretion system (TTSS) of Aeromonas salmonicida subsp. has been linked to virulence in salmonids. In this study, three TTSS effector genes, aexT, aopH or aopO, were inactivated by deletion, as was ascC, the gene encoding outer-membrane pore apparatus. Effects on assayed live challenge Atlantic salmon (Salmo salar). DeltaascC mutant strain avirulent both intraperitoneal (i.p.) injection and immersion, did not appear establish a clinically inapparent infection...

Physiological changes, elicited in animal immune tissues by exposure to pathogens, may be studied using functional genomics approaches. We created and characterized reciprocal suppression subtractive hybridization (SSH) cDNA libraries identify differentially expressed genes spleen head kidney of Atlantic cod ( Gadus morhua) challenged with intraperitoneal injections formalin-killed, atypical Aeromonas salmonicida. Of 4,154 ESTs from four libraries, 10 immune-relevant annotations were...

SUMMARY We have previously shown that Lepeophtheirus salmonis produces trypsin and prostaglandin E 2 (PGE ) are most likely responsible for the limited inflammatory response of Atlantic salmon to infection. After removal dopamine PGE , immunomodulatory activity unfractionated pools fractionated secretions was determined by examining effects on immune gene expression. Incubation macrophage‐enriched isolates head kidney cells with secretion + revealed a significant inhibition interleukin‐1β...

Survival, oxygen consumption ( ), total plasma cortisol and glucose levels gill heat‐shock protein 70 (hsp70) expression were measured in 10 50 g juvenile Atlantic cod Gadus morhua during an acute temperature increase (2° C h −1 ) to their critical thermal maximum. Ninety three per cent of the fish both size classes survived 24° C; however, mortality was 100% within 15 min reaching this temperature. The for increased significantly with temperature, peak values at 22° that c. 2·8‐fold those...

Abstract Background Daily and seasonal changes in temperature are challenges that fish within aquaculture settings cannot completely avoid, known to elicit complex organismal cellular stress responses. We conducted a large-scale gene discovery transcript expression study order better understand the genes potentially involved physiological aspects of caused by heat-shock. used suppression subtractive hybridization (SSH) cDNA library construction characterization identify transcripts were...

Aeromonas salmonicida subsp. salmonicida, a bacterial pathogen of Atlantic salmon, has no visible pili, yet its genome contains genes for three type IV pilus systems. One system, Tap, is similar to the Pseudomonas aeruginosa Pil and second, Flp, resembles Actinobacillus actinomycetemcomitans Flp pilus, while third homology mannose-sensitive hemagglutinin Vibrio cholerae. The latter system likely nonfunctional since eight genes, including gene encoding main pilin subunit, are deleted compared...

As part of an investigation the biochemical interactions between salmon louse Lepeophtheirus salmonis and Atlantic Salmo salar, we characterized protease activity in skin mucus noninfected infected with L. whole-body homogenate. Zymography revealed that from contained a series low-molecular-mass (17–22 kDa) serine proteases were not present salmon. Based on molecular mass, inhibition studies, affinity chromatography, was identified as being trypsin-like. Similar observed homogenate following...

The partial sequencing of two lipases from winter flounder Pseudopleuronectes americanus , one most closely related to gastric, lingual and lysosomal acid lipase other vertebrates bile salt‐activated lipase, is reported. Biochemical analyses enzymatic activity demonstrated the greater contribution made by relative neutral salt‐independent lipase. Using molecular techniques, tissue‐specific expression in pancreatic tissue triacylglycerol a wide variety organs was demonstrated. Furthermore,...

Nous avons surveille l'occurrence du copepode marin ectoparasite Lepeophtheirus salmonis et la prevalence des lesions causees par son activite alimentaire chez adultes de saumon rouge (Oncorhynchus nerka) retournant aux rivieres Sproat Stamp en passant l'inlet Alberni (Colombie-Britannique) 1990 1992-1993. Tous les saumons rouges examines etaient infestes L. salmonis, presentaient infestations plus intenses que ce qui avait ete observe jusque-la. La presence d'un nombre important parasites...

Nodaviruses and other RNA viruses have a profoundly negative impact on the global aquaculture industry. target nervous tissue causing viral necrosis, disease characterized by neurological damage, swimming abnormalities, morbidity. This study used functional genomic techniques to Atlantic cod (Gadus morhua) brain transcript expression responses asymptomatic high nodavirus carrier state intraperitoneal injection of polyriboinosinic polyribocytidylic acid (pIC). Reciprocal suppression...

Piscine reovirus (PRV) is a double stranded non-enveloped RNA virus detected in farmed and wild salmonids. This study examined the phylogenetic relationships among different PRV sequence types present samples from salmonids Western Canada US, including Alaska (US), British Columbia (Canada) Washington State (US). Tissues testing positive for were partially sequenced segment S1, producing 71 sequences that grouped into 10 unique types. Sequence analysis revealed no identifiable geographical...