Proliferative kidney disease (PKD) is a widespread temperature-dependent disease in salmonids caused by the myxozoan parasite, Tetracapsuloides bryosalmonae (Canning, Curry, Feist, Longshaw et Okamura, 1999) (Tb). Tb has a two-host life cycle, involving fish as an intermediate host and freshwater bryozoans as the definitive host. Although salmonids are acknowledged as hosts for the parasite, it is less clear which fish species are active hosts in the life cycle of Tb. Differences in infection dynamics have been observed between some fish species, which are thought to be related to the existence of two main Tb-strains, the American and European. Iceland, having three species of indigenous salmonids and positioned geographically between Europe and North America, is an ideal location to study the natural development of Tb in wild fish. The main aim of this study was to determine the genetic origin of Tb in Iceland and confirm whether mature spores are produced in Icelandic salmonids. In this study, Icelandic salmonids were infected with the European Tb-strain. In situ hybridisation revealed that intraluminal sporogonic stages, including mature spores, were commonly observed in all three salmonid species. The presence of intraluminal stages has previously been confirmed in brown trout Salmo trutta Linnaeus and Atlantic salmon S. salar Linnaeus in Europe, but they have only been observed in Arctic charr Salvelinus alpinus (Linnaeus) in North America, infected by the local strain. This is, therefore, the first time that sporogonic stages have been observed in Arctic charr in Europe, where fish are infected with the European Tb-strain. Our data strongly suggest that all the three salmonid species inhabiting Icelandic waters serve as active hosts in the life cycle of Tb. However, for full confirmation, transmission trials are needed.
- MeSH
- In Situ Hybridization veterinary MeSH
- Host-Parasite Interactions * MeSH
- Myxozoa growth & development physiology MeSH
- Fish Diseases parasitology MeSH
- Parasitic Diseases, Animal parasitology MeSH
- Trout * MeSH
- Salmo salar * MeSH
- Animals MeSH
- Check Tag
- Animals MeSH
- Publication type
- Journal Article MeSH
Neoparamoeba perurans is the aetiological agent of amoebic gill disease (AGD) in salmonids, however multiple other amoeba species colonise the gills and their role in AGD is unknown. Taxonomic assessments of these accompanying amoebae on AGD-affected salmon have previously been based on gross morphology alone. The aim of the present study was to document the diversity of amoebae colonising the gills of AGD-affected farmed Atlantic salmon using a combination of morphological and sequence-based taxonomic methods. Amoebae were characterised morphologically via light microscopy and transmission electron microscopy, and by phylogenetic analyses based on the 18S rRNA gene and cytochrome oxidase subunit I (COI) gene. In addition to N. perurans, 11 other amoebozoans were isolated from the gills, and were classified within the genera Neoparamoeba, Paramoeba, Vexillifera, Pseudoparamoeba, Vannella and Nolandella. In some cases, such as Paramoeba eilhardi, this is the first time this species has been isolated from the gills of teleost fish. Furthermore, sequencing of both the 18S rRNA and COI gene revealed significant genetic variation within genera. We highlight that there is a far greater diversity of amoebae colonising AGD-affected gills than previously established.
- MeSH
- Amebiasis parasitology veterinary MeSH
- Amoebozoa classification genetics ultrastructure MeSH
- Biodiversity * MeSH
- Phylogeny MeSH
- Microscopy MeSH
- Fish Diseases parasitology MeSH
- Electron Transport Complex IV genetics MeSH
- RNA, Ribosomal, 18S genetics MeSH
- Salmo salar parasitology MeSH
- Microscopy, Electron, Transmission MeSH
- Gills parasitology MeSH
- Animals MeSH
- Check Tag
- Animals MeSH
- Publication type
- Journal Article MeSH
Citrate synthase belongs between mitochondrial enzymes which are released from the meat tissue after cell membrane damage caused by ice crystal formation. The presence of this enzyme can indicate a previous freezing process. In this study, we determined citrate synthase activity for chilled and frozen/thawed meats (chicken, pork, beef, and salmon). As an additional factor, we examined a potential connection between microbial spoilage and increased enzyme activity. UV spectrophotometry was used for the evaluation of the citrate synthase activity. The effect of microbial spoilage on the enzyme activity was established through microbial analysis, which was carried out for two weeks for chilled and five months for frozen/thawed meats. The citrate synthase activity in the frozen/thawed samples was significantly higher than in the chilled samples. Dependence of microbial contamination and the increased activity of the citrate synthase was not observed. Our results suggest that there could be designed specific limits of citrate synthase activity for the resolution of chilled and frozen/thawed meats.
- MeSH
- Citrate (si)-Synthase analysis MeSH
- Chickens MeSH
- Salmon MeSH
- Meat analysis microbiology MeSH
- Swine MeSH
- Food Storage methods MeSH
- Cattle MeSH
- Spectrophotometry, Ultraviolet MeSH
- Freezing * MeSH
- Animals MeSH
- Check Tag
- Cattle MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- MeSH
- 25-Hydroxyvitamin D3 1-alpha-Hydroxylase isolation & purification blood MeSH
- Eels MeSH
- Hydroxycholecalciferols isolation & purification blood metabolism MeSH
- Hydroxylation physiology immunology radiation effects MeSH
- Liver enzymology metabolism MeSH
- Kidney enzymology metabolism MeSH
- Humans MeSH
- Salmon MeSH
- Bone Diseases, Metabolic diagnosis etiology prevention & control MeSH
- Metabolism physiology drug effects radiation effects MeSH
- Vitamin D Deficiency * diagnosis etiology prevention & control MeSH
- Dietary Supplements utilization MeSH
- Fishes classification MeSH
- Practice Guidelines as Topic MeSH
- Statistics as Topic MeSH
- Ultraviolet Rays * classification MeSH
- Vitamin D * physiology isolation & purification standards MeSH
- Check Tag
- Humans MeSH
- Publication type
- Case Reports MeSH
- MeSH
- Food Analysis * methods MeSH
- Chromatography, Gas methods utilization MeSH
- Fatty Acids, Omega-6 analysis isolation & purification MeSH
- Humans MeSH
- Salmon classification growth & development MeSH
- Fatty Acids, Omega-3 analysis isolation & purification MeSH
- Oncorhynchus classification growth & development MeSH
- Fish Proteins analysis isolation & purification MeSH
- Cod Liver Oil analysis isolation & purification metabolism MeSH
- Fishes * metabolism growth & development MeSH
- Salmo salar classification growth & development MeSH
- Salmonidae * classification growth & development MeSH
- Statistics as Topic MeSH
- Vitamin D isolation & purification MeSH
- Check Tag
- Humans MeSH
- Publication type
- Research Support, Non-U.S. Gov't MeSH
Growth of the aquaculture industry has triggered the need for research into the potential environmental impact of chemicals used by salmon farms to control diseases. In this study, the antiparasitic pesticides emamectin benzoate (EB), diflubenzuron (DI), teflubenzuron (TE), and cypermethrin (CP) were measured in sediments near salmon cages in southern Chile. Concentrations for EB were between 2.2 and 14.6ngg(-1), while the benzoylphenyl ureas DI and TE were detected in the ranges of 0.1 to 1.2ngg(-1) and 0.8 to 123.3ngg(-1), respectively. These results were similar to data reported for the Northern Hemisphere. On the other hand, the pyrethroid CP was detected in higher concentrations, ranging from 18.0 to 1323.7ngg(-1). According to reported toxicity data, this range represents a potential risk for benthic invertebrates. This report is the first baseline attempt at assessing antiparasitic pesticide levels in the Chilean Patagonia.
- MeSH
- Antiparasitic Agents analysis MeSH
- Benzamides analysis MeSH
- Diflubenzuron analysis MeSH
- Geologic Sediments chemistry MeSH
- Ivermectin analogs & derivatives analysis MeSH
- Salmon * MeSH
- Pesticides analysis MeSH
- Pyrethrins analysis MeSH
- Aquaculture * MeSH
- Animals MeSH
- Check Tag
- Animals MeSH
- Publication type
- Journal Article MeSH
- Geographicals
- Chile MeSH
Alternative reproductive tactics (ARTs) are prevalent in nature, where smaller parasitic males typically have better sperm quality than larger territorial guard males. At present, it is unclear what is causing this phenomenon. Our objective was to gain insights into sperm form and function by examining flagellar beating patterns (beat frequency, wave amplitude, bend length, bend angle, wave velocity) and biomechanical sperm metrics (velocity, hydrodynamic power output, propulsive efficiency) of wild spawning Chinook salmon ARTs. Ovarian fluid and milt were collected to form a series of eight experimental blocks, each composed of ovarian fluid from a unique female and sperm from a unique pair of parasitic jack and guard hooknose males. Sperm from each ART were activated in river water and ovarian fluid. Flagellar parameters were evaluated from recordings using high-speed video microscopy and biomechanical metrics were quantified. We show that ART has an impact on flagellar beating, where jacks had a higher bend length and bend angle than hooknoses. Activation media also impacted the pattern of flagellar parameters, such that beat frequency, wave velocity and bend angle declined, while wave amplitude of flagella increased when ovarian fluid was incorporated into activation media. Furthermore, we found that sperm from jacks swam faster than those from hooknoses and required less hydrodynamic power output to propel themselves in river water and ovarian fluid. Jack sperm were also more efficient at swimming than hooknose sperm, and propulsive efficiency increased when cells were activated in ovarian fluid. The results demonstrate that sperm biomechanics may be driving divergence in competitive reproductive success between ARTs.
- MeSH
- Sperm Tail physiology MeSH
- Biomechanical Phenomena MeSH
- Salmon physiology MeSH
- Sperm Motility * MeSH
- Ovary physiology MeSH
- Reproduction physiology MeSH
- Animals MeSH
- Check Tag
- Male MeSH
- Female MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Geographicals
- Ontario MeSH
1. This study examined hepatic cytochrome P450 (CYP450) response to dietary sesamin in combination with different n-6/n-3 fatty acid ratios in fish diet. Over a period of 4 months, fish were fed seven different experimental diets an n-6/n-3 FA ratio of either 0.5 or 1.0 in combination with two sesamin levels: low sesamin = 1.16 g/kg feed and high sesamin = 5.8 g/kg feed. Control diets did not contain sesamin. 2. The CYP450-associated activities of ethoxyresorufin O-deethylase (EROD), 7-benzyloxy-4-trifluoromethylcoumarin O-debenzylation (BFCOD), pentoxyresorufin O-depentylase (PROD), coumarin hydroxylase (COH), methoxyresorufin O-deethylase (MROD) and p-nitrophenol hydroxylase (PNPH) were significantly induced by dietary sesamin in a dose-related manner. 3. Expressions of the genes CYP1A1, CYP1A3, CYP3A, AhR1α, AhR2β, AhR2δ and PXR involved in the regulation of CYP450 activities, was not the primary source of this induction.
- MeSH
- Dioxoles pharmacology MeSH
- Liver drug effects enzymology MeSH
- Lignans pharmacology MeSH
- Plant Oils pharmacology MeSH
- Gene Expression Regulation drug effects MeSH
- Fish Oils pharmacology MeSH
- Salmo salar metabolism MeSH
- Cytochrome P-450 Enzyme System metabolism MeSH
- Xenobiotics metabolism MeSH
- Animals MeSH
- Check Tag
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
CZE has been applied to determination of thermodynamic acidity constants (pKa ) of ionogenic groups and actual ionic mobilities of polyprotic peptides-synthetic human and salmon gonadotropin-releasing hormones and their derivatives and fragments. First, the mixed acidity constants, pKa,imix, of ionogenic groups, and actual ionic mobilities, mi , of gonadotropin-releasing hormone peptides were determined by nonlinear regression analysis of pH dependence of their effective electrophoretic mobilities. The effective mobilities were measured by CZE in a series of BGEs within a broad pH range (1.80-12.10), at constant ionic strength (25 mM) and reference temperature (25°C). Second, the pKa,imix values were recalculated to thermodynamic pKa s using the Debye-Hückel theory. Thermodynamic pKa of carboxyl groups was estimated to be in the range of 2.5-3.3 for C-terminal amino acids of the above peptides, and 5.2 for glutamic acid in the middle of peptide chain; pKa of imidazolyl group of histidine residues was in the range of 5.7-6.8, pKa of N-terminal amino group of the peptide with free N-terminus was equal to 6.2, pKa of phenol group of tyrosine residues was in the range of 9.8-10.8, and pKa of guanidinyl group or arginine residues reached values 11.1-11.3, depending on the position of the residues in the peptide and on the amino acid sequence of the peptide. Absolute values of actual ionic mobilities of peptides with charge number ±2 were in the range (14.6-18.6) × 10(-9) m(2) V(-1) s(-1) , and ionic mobilities of peptides with charge number ±1 reached values (6.5-12.9) × 10(-9) m(2) V(-1) s(-1) .
- MeSH
- Electrophoresis, Capillary methods MeSH
- Gonadotropin-Releasing Hormone chemistry MeSH
- Ions chemistry MeSH
- Hydrogen-Ion Concentration MeSH
- Humans MeSH
- Salmon MeSH
- Nonlinear Dynamics MeSH
- Thermodynamics MeSH
- Animals MeSH
- Check Tag
- Humans MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
