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Csaba Szekely - One of the best experts on this subject based on the ideXlab platform.
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differential survival of 3rd stage larvae of contracaecum rudolphii type b infecting common bream Abramis brama and common carp cyprinus carpio
Parasitology Research, 2019Co-Authors: Kalman Molnar, Csaba Szekely, Ferenc Baska, Per W Kania, Tamas Muller, B Nowak, Kurt BuchmannAbstract:The main fish host reaction to an infection with third stage anisakid nematode larvae is a response in which host immune cells (macrophages, granulocytes, lymphocytes) in affected internal organs initially are attracted to the parasite whereafter fibroblasts may enclose the parasite forming granuloma. Generally, the reaction is non-lethal to the parasite which may survive for years in the fish host retaining infectivity to the final host. This may also apply for the anisakid nematode Contracaecum rudolphii (having the adult stage in cormorants, using copepods as first intermediate/paratenic host and zooplankton feeding fish as paratenic hosts). The present study has shown that most Contracaecum rudolphii larvae survive in bream (Abramis brama) (from Lake Balaton, Hungary) whereas the majority of the nematode larvae die in Cyprinus carpio (from Lake Heviz, directly connected to Lake Balaton). Both cyprinid host species interacted with the nematode larvae through establishing a marked cellular encapsulation around them but with different effects. The differential survival in common carp and bream may theoretically be explained by ecological factors, such as the environmental temperature which either directly or indirectly affect the development of nematode larvae, and/or intrinsic host factors, such as differential immune responses and host genetics.
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complete life cycle of myxobolus rotundus myxosporea myxobolidae a gill myxozoan of common bream Abramis brama
Diseases of Aquatic Organisms, 2009Co-Authors: Csaba Szekely, Sascha L Hallett, Stephen D Atkinson, Kalman MolnarAbstract:The life cycle of Myxobolus rotundus Nemeczek, 1911, a myxosporean parasite of the gills of common bream Abramis brama L., was studied under laboratory conditions. Mature Myxobolus spp. spores from plasmodia in the gills of wild bream were used to infect naive oligochaete worms in a flow-through system of aquaria. Triactinomyxon-type actinospores were released from the oligochaetes 1 yr later and allowed to continually flow into a tank containing uninfected bream fry. The gills of the fry were checked for development of plasmodia in squash preparations 3 d post-exposure, and then at weekly intervals for 8 wk. Tissue samples were fixed at each time point. Developing plasmodia were first observed 17 d post-exposure (Day 17). Mature spores were collected from plasmodia on Day 56 and were added to plastic dishes containing parasite-free Tubifex tubifex oligochaetes. Second-generation actinospores were released from these worms 8 mo post-exposure, and were morphologically identical to first-generation spores. Myxospores obtained from the bream fry were morphologically identical to those identified in wild bream as M. rotundus. Small subunit ribosomal RNA gene sequences obtained from first- and second-generation actinospores and the bream fry myxospores were 100% similar to M. rotundus spores from the original wild fish.
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infection of the heart of the common bream Abramis brama l with myxobolus s l dogieli myxozoa myxobolidae
Journal of Fish Diseases, 2008Co-Authors: Kalman Molnar, Gabor Cech, Csaba SzekelyAbstract:Myxobolus dogieli Bykhovskaya-Pavlovskaya & Bykhovski, 1940 is regarded as a site specific myxosporean, infecting the heart of cyprinid fish. During a survey of the myxosporean fauna of Lake Balaton fish, heart myxobolosis was found in the common bream, Abramis brama, with heavy infection of the ventricle and the bulbus arteriosus in some infected bream. Developing and mature plasmodia were mostly in the connective tissue of the subepicardium and subendocardium. Plasmodia developing in the subendocardium protruded into the lumen of the heart, while plasmodia developing in the subepicardium protruded over the epicardium forming large sausage-like outgrowths. Plasmodia with mature spores were found in the summer. The shape and size of the spores corresponded to those of the original description. Phylogenetic analysis based on the 18S rDNA sequence of M. dogieli showed that this species fit well in the genus Myxobolus. As no molecular data are available on spores from the type host, common carp, the species studied by us is temporarily designated as Myxobolus s.l. dogieli.
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myxobolus infection of the gills of common bream Abramis brama l in lake balaton and in the kis balaton reservoir hungary
Acta Veterinaria Hungarica, 1999Co-Authors: Kalman Molnar, Csaba SzekelyAbstract:During a five-year survey including studies on the parasite fauna of bream (Abramis brama), four gill-parasitic Myxobolus species (M. bramae, M. hungaricus, M. impressus and M. macrocapsularis) were recorded in a total of 313 breams from Lake Balaton. The commonest species, M. bramae showed a prevalence of 33%, while the other species occurred sporadically. Myxobolus bramae and M. macrocapsularis infected the tips of the gill filaments and caused both intralamellar and interlamellar infection. Intralamellar plasmodia of small size developed in the capillary network of the gill lamellae whereas the much larger interlamellar plasmodia were formed in the arteria afferens. The intralamellar plasmodia of M. hungaricus always infected the basal or central part of the gill filaments. In contrast to the above species developing in the blood vessels, M. impressus proved to be an epithelial parasite, as its plasmodia always developed in the adjacent gill filaments of two opposite haemibranchia, in the stratified ep...
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myxobolus infection of the gills of common bream Abramis brama l in lake balaton and in the kis balaton reservoir hungary
Acta Veterinaria Hungarica, 1999Co-Authors: Kalman Molnar, Csaba SzekelyAbstract:During a five-year survey including studies on the parasite fauna of bream (Abramis brama), four gill-parasitic Myxobolus species (M. bramae, M. hungaricus, M. impressus and M. macrocapsularis) were recorded in a total of 313 breams from Lake Balaton. The commonest species, M. bramae showed a prevalence of 33%, while the other species occurred sporadically. Myxobolus bramae and M. macrocapsularis infected the tips of the gill filaments and caused both intralamellar and interlamellar infection. Intralamellar plasmodia of small size developed in the capillary network of the gill lamellae whereas the much larger interlamellar plasmodia were formed in the arteria afferens. The intralamellar plasmodia of M. hungaricus always infected the basal or central part of the gill filaments. In contrast to the above species developing in the blood vessels, M. impressus proved to be an epithelial parasite, as its plasmodia always developed in the adjacent gill filaments of two opposite haemibranchia, in the stratified epithelium between the respiratory plates, causing changes of the haemibranchium which were well visible even by the naked eye.
Weylim Wong - One of the best experts on this subject based on the ideXlab platform.
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attachment ability of a clamp bearing fish parasite diplozoon paradoxum monogenea on gills of the common bream Abramis brama
The Journal of Experimental Biology, 2013Co-Authors: Weylim WongAbstract:Monogeneans, which are mainly fish ectoparasites, use various types of haptoral (posterior) attachment apparatus to secure their attachment onto their hosts. However, it remains unclear how strongly a monogenean can attach onto its host. In the present study, we aimed for the first time to (1) measure pull-off forces required to detach a pair of clamp-bearing monogeneans, Diplozoon paradoxum from gills of Abramis brama and (2) determine the contribution of muscles to the clamp movements. An average force of 6.1 ± 2.7 mN (about 246 times of the animals’ weight) was required to dislodge a paired D. paradoxum vertically from the gills. There were significant differences (p < 0.05, Tukey test) between the widths of clamp openings in D. paradoxum treated in three different solutions: the widest clamp openings were observed in the monogeneans treated in 100 mM potassium chloride solution (58.26 ± 13.44 µm), followed by those treated in 20 mM magnesium chloride solution (37.91 ± 7.58 µm), and finally those treated in filtered lake water (20.16 ± 8.63 µm). This suggests that the closing of the clamps is probably not due to the continuous contraction of extrinsic muscles but caused by the elasticity of the clamp material and that muscle activity is required for clamp opening.
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attachment ability of a clamp bearing fish parasite diplozoon paradoxum monogenea on gills of the common bream Abramis brama
The Journal of Experimental Biology, 2013Co-Authors: Weylim Wong, Stanislav N GorbAbstract:Monogeneans, which are mainly fish ectoparasites, use various types of haptoral (posterior) attachment apparatus to secure their attachment onto their hosts. However, it remains unclear how strongly a monogenean can attach onto its host. In the present study, we aimed for the first time to (1) measure pull-off forces required to detach a pair of clamp-bearing monogeneans, Diplozoon paradoxum, from gills of Abramis brama and (2) determine the contribution of muscles to the clamp movements. A mean force of 6.1±2.7 mN (~246 times the animals' weight) was required to dislodge a paired D. paradoxum vertically from the gills. There were significant differences (P<0.05, Tukey test) between the widths of clamp openings in D. paradoxum treated in three different solutions: the widest clamp openings were observed in the monogeneans treated in 100 mmol l(-1) potassium chloride solution (58.26±13.44 μm), followed by those treated in 20 mmol l(-1) magnesium chloride solution (37.91±7.58 μm), and finally those treated in filtered lake water (20.16±8.63 μm). This suggests that the closing of the clamps is probably not due to the continuous contraction of extrinsic muscles but is caused by the elasticity of the clamp material and that muscle activity is required for clamp opening.
Kalman Molnar - One of the best experts on this subject based on the ideXlab platform.
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differential survival of 3rd stage larvae of contracaecum rudolphii type b infecting common bream Abramis brama and common carp cyprinus carpio
Parasitology Research, 2019Co-Authors: Kalman Molnar, Csaba Szekely, Ferenc Baska, Per W Kania, Tamas Muller, B Nowak, Kurt BuchmannAbstract:The main fish host reaction to an infection with third stage anisakid nematode larvae is a response in which host immune cells (macrophages, granulocytes, lymphocytes) in affected internal organs initially are attracted to the parasite whereafter fibroblasts may enclose the parasite forming granuloma. Generally, the reaction is non-lethal to the parasite which may survive for years in the fish host retaining infectivity to the final host. This may also apply for the anisakid nematode Contracaecum rudolphii (having the adult stage in cormorants, using copepods as first intermediate/paratenic host and zooplankton feeding fish as paratenic hosts). The present study has shown that most Contracaecum rudolphii larvae survive in bream (Abramis brama) (from Lake Balaton, Hungary) whereas the majority of the nematode larvae die in Cyprinus carpio (from Lake Heviz, directly connected to Lake Balaton). Both cyprinid host species interacted with the nematode larvae through establishing a marked cellular encapsulation around them but with different effects. The differential survival in common carp and bream may theoretically be explained by ecological factors, such as the environmental temperature which either directly or indirectly affect the development of nematode larvae, and/or intrinsic host factors, such as differential immune responses and host genetics.
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complete life cycle of myxobolus rotundus myxosporea myxobolidae a gill myxozoan of common bream Abramis brama
Diseases of Aquatic Organisms, 2009Co-Authors: Csaba Szekely, Sascha L Hallett, Stephen D Atkinson, Kalman MolnarAbstract:The life cycle of Myxobolus rotundus Nemeczek, 1911, a myxosporean parasite of the gills of common bream Abramis brama L., was studied under laboratory conditions. Mature Myxobolus spp. spores from plasmodia in the gills of wild bream were used to infect naive oligochaete worms in a flow-through system of aquaria. Triactinomyxon-type actinospores were released from the oligochaetes 1 yr later and allowed to continually flow into a tank containing uninfected bream fry. The gills of the fry were checked for development of plasmodia in squash preparations 3 d post-exposure, and then at weekly intervals for 8 wk. Tissue samples were fixed at each time point. Developing plasmodia were first observed 17 d post-exposure (Day 17). Mature spores were collected from plasmodia on Day 56 and were added to plastic dishes containing parasite-free Tubifex tubifex oligochaetes. Second-generation actinospores were released from these worms 8 mo post-exposure, and were morphologically identical to first-generation spores. Myxospores obtained from the bream fry were morphologically identical to those identified in wild bream as M. rotundus. Small subunit ribosomal RNA gene sequences obtained from first- and second-generation actinospores and the bream fry myxospores were 100% similar to M. rotundus spores from the original wild fish.
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infection of the heart of the common bream Abramis brama l with myxobolus s l dogieli myxozoa myxobolidae
Journal of Fish Diseases, 2008Co-Authors: Kalman Molnar, Gabor Cech, Csaba SzekelyAbstract:Myxobolus dogieli Bykhovskaya-Pavlovskaya & Bykhovski, 1940 is regarded as a site specific myxosporean, infecting the heart of cyprinid fish. During a survey of the myxosporean fauna of Lake Balaton fish, heart myxobolosis was found in the common bream, Abramis brama, with heavy infection of the ventricle and the bulbus arteriosus in some infected bream. Developing and mature plasmodia were mostly in the connective tissue of the subepicardium and subendocardium. Plasmodia developing in the subendocardium protruded into the lumen of the heart, while plasmodia developing in the subepicardium protruded over the epicardium forming large sausage-like outgrowths. Plasmodia with mature spores were found in the summer. The shape and size of the spores corresponded to those of the original description. Phylogenetic analysis based on the 18S rDNA sequence of M. dogieli showed that this species fit well in the genus Myxobolus. As no molecular data are available on spores from the type host, common carp, the species studied by us is temporarily designated as Myxobolus s.l. dogieli.
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myxobolus infection of the gills of common bream Abramis brama l in lake balaton and in the kis balaton reservoir hungary
Acta Veterinaria Hungarica, 1999Co-Authors: Kalman Molnar, Csaba SzekelyAbstract:During a five-year survey including studies on the parasite fauna of bream (Abramis brama), four gill-parasitic Myxobolus species (M. bramae, M. hungaricus, M. impressus and M. macrocapsularis) were recorded in a total of 313 breams from Lake Balaton. The commonest species, M. bramae showed a prevalence of 33%, while the other species occurred sporadically. Myxobolus bramae and M. macrocapsularis infected the tips of the gill filaments and caused both intralamellar and interlamellar infection. Intralamellar plasmodia of small size developed in the capillary network of the gill lamellae whereas the much larger interlamellar plasmodia were formed in the arteria afferens. The intralamellar plasmodia of M. hungaricus always infected the basal or central part of the gill filaments. In contrast to the above species developing in the blood vessels, M. impressus proved to be an epithelial parasite, as its plasmodia always developed in the adjacent gill filaments of two opposite haemibranchia, in the stratified ep...
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redescription of myxobolus hungaricus jaczo 1940 myxosporea myxobolidae a parasite of bream Abramis brama l
Acta Veterinaria Hungarica, 1999Co-Authors: Ferenc Baska, Kalman MolnarAbstract:Myxobolus hungaricusJaczo, 1940 forms relatively large plasmodia on the gills of bream (Abramis brama). The authors give a redescription of this deficiently described parasite on the basis of spores collected from the original habitat, which spores are indicated as a neotype. The plasmodia of the parasite can be found on the gills typically in the spring months, and are located in the central part of the gill filaments. They start to develop in the lumen of capillaries of the secondary lamellae and remain in intralamellar location also after they have reached the mature stage. The spores have a very characteristic shape, as on the surface of the spore valves a distinctly emerging ridge runs parallel to the sutural line. In addition to breams from the typical habitat, Lake Balaton, the plasmodia ofM. hungaricuscould be detected also on breams originating from the river Danube.
F A Sibbing - One of the best experts on this subject based on the ideXlab platform.
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efficiency of feeding on zebra mussel dreissena polymorpha by common bream Abramis brama white bream blicca bjoerkna and roach rutilus rutilus the effects of morphology and behavior
Canadian Journal of Fisheries and Aquatic Sciences, 1996Co-Authors: L A J Nagelkerke, F A SibbingAbstract:We compared efficiencies of feeding on zebra mussel ( Dreissena polymorpha ) by three syntopic cyprinids: common bream ( Abramis brama ), white bream ( Blicca bjoerkna ), and roach ( Rutilus rutilus ). Empirical feeding efficiency (the ratio of food energy content to food capture and processing costs) is largely determined by the time needed to handle prey, rather than by the energy required for specific feeding actions, such as detaching and crushin g the mussel. The highest individual feeding efficiency values were achieved by large white bream and roach, while common brea m performed poorly. Maximal and optimal prey sizes were highest in roach. X-ray movies showed that in roach the dimensio ns of the oral gape, pharyngeal slit, and chewing cavity all matched, and thus limited, maximal prey size. In common brea m and white bream prey size is limited by pharyngeal crushing power. The ability of roach to process larger mussels is base d on the larger static crushing forces that can be exerted by its stout pharyngeal jaws; this could contribute to a strong position in competing for mollusks, most probably at the expense of its filter-feeding capacity. An integration of morphology, behavior, and performance helps to explain feeding efficiency differences among fish species and could eventually provide insights into mechanisms of trophic segregation.
Pascal Poncin - One of the best experts on this subject based on the ideXlab platform.
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a comparative study of sexual product quality in f1 hybrids of the bream Abramis brama the silver bream blicca bjoerkna
Fisheries Science, 2012Co-Authors: Billy Nzau Matondo, Michael Ovidio, Jeanclaude Philippart, Pascal PoncinAbstract:The gonadosomatic index at spawning, absolute fecundity, and egg size for the female sexual products as well as the density and consistency of semen for the male sexual products were examined in cultured Abramis brama × Blicca bjoerkna F1 hybrids and compared with the parental species at their first sexual maturity. Females ovulated under environmental conditions, and their eggs were weighed, counted and measured. Semen of males was macroscopically examined and spermatozoa counted using a hemocytometer. Results revealed that hybridization affected the quality of female and male gametes but with an overlap between hybrids and parents. The gonadosomatic index and fecundity were significantly lower than those of parental species. Egg sizes in hybrids showed a parental effect but to the benefit of hybrids. Semen of hybrids was more diluted which was classified into two groups: the white semen overlapping slightly with parents and the aqueous without any overlap with parents. Overlapped areas between hybrids and parents in term of quality of sexual products could translate that females and males of these hybrids have the biological capacity to produce high quality gametes and thus, a greater chance to produce F2 and backcross generations in rivers.
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relationships between circulating androgens aggressive behaviour and breeding tubercles in males of the common bream Abramis brama l in an aquarium environment
Fish Physiology and Biochemistry, 2011Co-Authors: Pascal Poncin, Nzau B Matondo, C Termol, Patrick Kestemont, Jeanclaude PhilippartAbstract:In this study, relationships between circulating androgens, aggressive behaviour and breeding tubercles in males of common bream Abramis brama were examined in an aquarium environment. The breeding tubercles of fish were counted, the number of attacks was quantified by male status and circulating rates of testosterone and 11-ketotestosterone from blood plasma were analysed using radioimmunoassay procedures. The results revealed that no significant differences were found between circulating testosterone and 11-ketotestosterone in territorial and nonterritorial males. Furthermore, no significant correlations were found between circulating androgens, androgens and aggression, androgens and tubercles and breeding tubercles and aggression in common bream by male status. However, territorial fish displayed a significantly higher level of aggressive behaviour and breeding tubercles than nonterritorial fish. In natural environments, the occurrence of breeding tubercles during the spawning season could contribute to identifying the behavioural status of common bream males.
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reproductive behaviour and sexual production in the first generation hybrids of roach rutilus rutilus l x common bream Abramis brama l
Journal of Applied Ichthyology, 2011Co-Authors: Billy Nzau Matondo, Michael Ovidio, Jeanclaude Philippart, Pascal PoncinAbstract:Summary The aim of this study was to further test the viability of the roach Rutilus rutilus × common bream Abramis brama hybrid in terms of reproductive behaviour and sexual production. Egg release, mating and aggressive acts in reproductive behaviour, as well as absolute fecundity and sperm density in milt for sexual production were examined in the first generation of these hybrids at their first sexual maturity. The F2 and backcrosses of hybrids were also studied. The results revealed that these hybrids expressed a normal and typical mating behaviour, producing viable gametes. Under experimental reproduction between hybrids (hybrid reproduction), the number of egg-release acts (range, 21–66) was nearer (χ2 test, P > 0.05) the number of mating acts (11–65). Moreover, hybrid males exhibited territorial and aggressive behaviours. However, in experimental reproduction of female and male hybrids mixed with parental males (mixed reproduction), the egg-release act and the mating act were inhibited by the intense territorial and aggressive activities of the common bream male. Absolute fecundity values (median, 6.0 × 103 eggs and >14 × 109 spermatozoa ml−1, respectively). Nevertheless, these hybrids were fertile. F2 and backcross generations were produced, although with a significantly lower viable hatching rate (FEP test, P < 0.05) in F2 individuals from the female and its corresponding hybrid male (<6%), indicating a very low chance of survival in rivers.
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hybridization behaviour between two common european cyprinid fish species silver bream blicca bjoerkna and common bream Abramis brama in a controlled environment
Animal Biology, 2009Co-Authors: Billy Nzau Matondo, Michael Ovidio, Jeanclaude Philippart, Pascal PoncinAbstract:The egg release–mating comparison, heterospecific matings and mating success under two hybridization conditions – (i) mixing one sex per species and (ii) mixing both sexes from each species – were investigated to determine whether silver bream Blicca bjoerkna and common bream Abramis brama can hybridize in nature.The results revealed that non-matings in hybridization experiments of silver bream females × common bream males can be explained by territorial and aggressiveness activities observed in common bream. In common bream females × silver bream males, heterospecific matings were observed but their numbers were significantly lower than the spawning numbers, and in this experiment, a female mated with one to four heterospecific males. In mixing both sexes from both species, similar spawning – mating numbers were observed but heterospecific matings accounted for only 27% of the total matings, with 24% accounting for heterospecific matings between common bream females and silver bream males, directly or by opportunism. Mating success was characterized by the occurrence of fertilized eggs after matings.Natural hybridization occurred preferentially between common bream females and silver bream males.
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hybridization success of three common european cyprinid species rutilus rutilus blicca bjoerkna and Abramis brama and larval resistance to stress tests
Fisheries Science, 2007Co-Authors: Billy Nzau Matondo, Michael Ovidio, Pascal Poncin, Tampwo Alain Kakesa, Lunkayilakio Soleil Wamuini, Jeanclaude PhilippartAbstract:Hybridization success at early developmental stages and larval resistance to osmotic, thermal and fasting tests in roach Rutilus rutilus, silver bream Blicca bjoerkna, common bream Abramis brama and their F1 hybrids were investigated. Results revealed that hybrid survival rates were similar to parents. At the eyed embryo stage, however, a maternal effect was observed as a general trend during hatchling and larval stages. After these stages, hybrids displayed a higher survival rate than their parents. Under stress tests, no survival was observed after 40 min for osmotic and thermal shocks and after 24 days for the prolonged fasting test in these species and their F1 hybrids. The median survivals of hybrids were intermediate between the two parents. For total mortality, hybrids were also affected by a maternal effect but to the advantage of the hybrids.
