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David K. Cone - One of the best experts on this subject based on the ideXlab platform.
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Supplemental diagnosis of Gyrodactylus nebulosus Kritsky and Mizelle, 1968 (Monogenea) on 0+ age Ameiurus nebulosus (Siluriformes) considered for commercial grow-out in Southwestern Nova Scotia, Canada.
Parasitology research, 2020Co-Authors: Eric Leis, Roland Leblanc, Russell H. Easy, Hillary Dort, David K. ConeAbstract:Gyrodactylus nebulosus Kritsky and Mizelle, 1968 is reported for the first time from brown bullhead Ameiurus nebulosus (Siluriformes; Ictaluridae) in Nova Scotia. The study results from a screening of parasites with the potential to disrupt commercial rearing of wild-caught young-of-the-year (YOY) brown bullhead. Infected YOY were collected July 30, 2018 and estimated to be 3 weeks old. Eight of 10 fish were infected. Mean intensity was 3.1 ± 3.5 with a range of 1–10. The parasite occurred all over the body surface, but particularly on the ventral regions of the head including the base of the maxillary barbels. Diagnostically important features of the anchors, ventral bar/shield, marginal hooks, and male copulatory organ are described. A partial sequence of the 18S rRNA gene (432 bp) is included and represents the first confirmed molecular data for this species. Molecular analysis revealed a high similarity (99.3%) to a Gyrodactylus sp. reported from the same host, A. nebulosus, in Ontario and the next closest similarity (96.9%) to Gyrodactylus fairporti Van Cleave, 1921 from Ameiurus melas in Wisconsin. The report extends the known distribution of G. nebulosus from North Dakota, Iowa, and Ontario to Nova Scotia. The study concludes that any commercial venture to harvest local YOY brown bullhead from the wild for intense grow-out in captivity should include appropriate quarantine and therapeutic treatments for G. nebulosus as part of the operation.
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Supplemental diagnosis of Gyrodactylus fairporti Van Cleave, 1921 (Monogenea) from 1 month old black bullhead (Ameiurus melas) in riverside pools in Wisconsin
Parasitology research, 2018Co-Authors: Eric Leis, Russell H. Easy, David K. ConeAbstract:Samples of Gyrodactylus fairporti Van Cleave, 1921 from young-of-the-year black bullhead (Ameiurus melas) stranded in riverside pools of the Black River (La Crosse County,) WI, USA, are used to supplement the species diagnosis, including new details on the marginal hook sickles, the male copulatory organ (MCO), and 18S rRNA gene sequence data. The anchors of G. fairporti are relatively long and thin, 58.2 ± 1.2 μm in length; roots 15.5 ± 1.0 μm; shaft 38.1 ± 1.5 μm; point 31.3 ± 1.5 μm. The ventral bar is 19.4 ± 0.4 μm wide and 5.7 ± 0.9 μm long, with small anterolateral processes, 2.0 ± 0.6 μm long, and an almost rectangular posterior shield 15.5 ± 1.1 μm in length. The marginal hooks are 29.2 ± 1.0 μm long, with the handle 23.9 ± 1.2 μm in length. These measurements are similar to those reported from Iowa and Alabama, with the additional observation of the anchor point bending outwardly halfway along its length. The marginal hook sickle blade leaves the base angled ventrally away from the longitudinal axis; the sickle point is short; the toe has a rounded shelf and the heel is small, thin, and rounded. The MCO has eight small spines, two large ones laterally and the others of various lengths, with two of the smallest spines being slightly out-of-line compared with all the others. The taxonomy of G. fairporti is compared to Gyrodactylus ictaluri Rogers, 1967 and G. nebulosus Kritsky & Mizelle, 1967, the other two species known from captive and wild ictalurids endemic to North America. The three species all have a relatively compact ventral bar with short anterolateral processes, a short almost rectangular ventral bar membrane, an MCO with up to eight small spines of varying length, and a hook sickle angled ventrally. Diagnostically, the species are readily identified by the total length and shape of the anchors. G. fairporti bears the longest (53–65 μm) and most slender anchors of the trio, G. nebulosus intermediate (49–51 μm) and G. ictaluri with the shortest and stoutest (40–45 μm) of these species. A BLAST search of a partial (413 bp) 18S rRNA gene showed the highest similarity with Gyrodactylus sp. reported from Ameiurus nebulosus (Siluriformes) in Ontario.
Eric Leis - One of the best experts on this subject based on the ideXlab platform.
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Morphometric and genetic evidence for cryptic diversity in Gyrodactylus (Monogenea) infecting non-native European populations of Ameiurus nebulosus and A. melas.
Parasitology, 2020Co-Authors: Markéta Ondračková, Mária Seifertová, Anna Bryjová, Eric Leis, Pavel JurajdaAbstract:Gyrodactylid parasites were observed on non-native populations of North-American freshwater catfishes, Ameiurus nebulosus and Ameiurus melas (Siluriformes: Ictaluridae), at several sites in the Elbe River basin, Czech Republic, Europe. Using a combination of morphological and genetic analyses, the parasites infecting A. nebulosus were determined to be Gyrodactylus nebulosus, a North American parasite co-introduced to Europe along with its Ameiurus fish hosts. Subtle morphometrical differences, as well as seasonal variations, were observed among parasites collected from A. nebulosus and A. melas. The host-related variation was further supported through genetic analysis of the partial 18S rDNA, ITS1-5.8S-ITS2 and COI, showing 0.2, 3.0 and 4.8% divergence, respectively. Consistent genetic differences indicated there were two distinct genotypes. Subtle morphological differences associated with the shape of sickle toe, anchor root and ventral bar membrane, according to host species, also supported the description of a new cryptic species, Gyrodactylus melas n. sp., infecting A. melas. Multivariate morphometrical analysis of haptoral hard parts showed significant differences between the anchor lengths of G. nebulosus and G. melas n. sp. However, the measurements of the haptoral hard structures partially overlapped between species, limiting the usage of these parameters for species delineation.
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Supplemental diagnosis of Gyrodactylus nebulosus Kritsky and Mizelle, 1968 (Monogenea) on 0+ age Ameiurus nebulosus (Siluriformes) considered for commercial grow-out in Southwestern Nova Scotia, Canada.
Parasitology research, 2020Co-Authors: Eric Leis, Roland Leblanc, Russell H. Easy, Hillary Dort, David K. ConeAbstract:Gyrodactylus nebulosus Kritsky and Mizelle, 1968 is reported for the first time from brown bullhead Ameiurus nebulosus (Siluriformes; Ictaluridae) in Nova Scotia. The study results from a screening of parasites with the potential to disrupt commercial rearing of wild-caught young-of-the-year (YOY) brown bullhead. Infected YOY were collected July 30, 2018 and estimated to be 3 weeks old. Eight of 10 fish were infected. Mean intensity was 3.1 ± 3.5 with a range of 1–10. The parasite occurred all over the body surface, but particularly on the ventral regions of the head including the base of the maxillary barbels. Diagnostically important features of the anchors, ventral bar/shield, marginal hooks, and male copulatory organ are described. A partial sequence of the 18S rRNA gene (432 bp) is included and represents the first confirmed molecular data for this species. Molecular analysis revealed a high similarity (99.3%) to a Gyrodactylus sp. reported from the same host, A. nebulosus, in Ontario and the next closest similarity (96.9%) to Gyrodactylus fairporti Van Cleave, 1921 from Ameiurus melas in Wisconsin. The report extends the known distribution of G. nebulosus from North Dakota, Iowa, and Ontario to Nova Scotia. The study concludes that any commercial venture to harvest local YOY brown bullhead from the wild for intense grow-out in captivity should include appropriate quarantine and therapeutic treatments for G. nebulosus as part of the operation.
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Supplemental diagnosis of Gyrodactylus fairporti Van Cleave, 1921 (Monogenea) from 1 month old black bullhead (Ameiurus melas) in riverside pools in Wisconsin
Parasitology research, 2018Co-Authors: Eric Leis, Russell H. Easy, David K. ConeAbstract:Samples of Gyrodactylus fairporti Van Cleave, 1921 from young-of-the-year black bullhead (Ameiurus melas) stranded in riverside pools of the Black River (La Crosse County,) WI, USA, are used to supplement the species diagnosis, including new details on the marginal hook sickles, the male copulatory organ (MCO), and 18S rRNA gene sequence data. The anchors of G. fairporti are relatively long and thin, 58.2 ± 1.2 μm in length; roots 15.5 ± 1.0 μm; shaft 38.1 ± 1.5 μm; point 31.3 ± 1.5 μm. The ventral bar is 19.4 ± 0.4 μm wide and 5.7 ± 0.9 μm long, with small anterolateral processes, 2.0 ± 0.6 μm long, and an almost rectangular posterior shield 15.5 ± 1.1 μm in length. The marginal hooks are 29.2 ± 1.0 μm long, with the handle 23.9 ± 1.2 μm in length. These measurements are similar to those reported from Iowa and Alabama, with the additional observation of the anchor point bending outwardly halfway along its length. The marginal hook sickle blade leaves the base angled ventrally away from the longitudinal axis; the sickle point is short; the toe has a rounded shelf and the heel is small, thin, and rounded. The MCO has eight small spines, two large ones laterally and the others of various lengths, with two of the smallest spines being slightly out-of-line compared with all the others. The taxonomy of G. fairporti is compared to Gyrodactylus ictaluri Rogers, 1967 and G. nebulosus Kritsky & Mizelle, 1967, the other two species known from captive and wild ictalurids endemic to North America. The three species all have a relatively compact ventral bar with short anterolateral processes, a short almost rectangular ventral bar membrane, an MCO with up to eight small spines of varying length, and a hook sickle angled ventrally. Diagnostically, the species are readily identified by the total length and shape of the anchors. G. fairporti bears the longest (53–65 μm) and most slender anchors of the trio, G. nebulosus intermediate (49–51 μm) and G. ictaluri with the shortest and stoutest (40–45 μm) of these species. A BLAST search of a partial (413 bp) 18S rRNA gene showed the highest similarity with Gyrodactylus sp. reported from Ameiurus nebulosus (Siluriformes) in Ontario.
Thomas Jones - One of the best experts on this subject based on the ideXlab platform.
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malignant melanoma of brown bullhead Ameiurus nebulosus in lake memphremagog vermont quebec
Journal of Fish Diseases, 2020Co-Authors: Vicki S. Blazer, Cassidy H. Shaw, Cheyenne R. Smith, Peter Emerson, Thomas JonesAbstract:In 2012, brown bullhead (Ameiurus nebulosus) with large, raised, black growths were first reported from multiple areas within the Vermont portion of Lake Memphremagog. Subsequent surveys conducted from 2014 to 2017 at two sites within the lake indicated a prevalence of 30% in adult brown bullhead 200 mm and above total length. These lesions ranged from slightly raised smooth black areas to large nodular areas on the body surface and fins and within the oral cavity. Microscopically, these lesions were determined to be malignant melanoma with invasion into surrounding hypodermis, skeletal muscle and bone as well as metastases to gill, ovary and intestine. Liver neoplasms were also observed in 8% of the bullhead collected from Lake Memphremagog in 2015. Neither skin nor liver neoplasms were noted in Ticklenaked Pond, a site used for comparison.
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Malignant melanoma of brown bullhead (Ameiurus nebulosus) in Lake Memphremagog, Vermont/Quebec.
Journal of fish diseases, 2019Co-Authors: Vicki S. Blazer, Cassidy H. Shaw, Cheyenne R. Smith, Peter Emerson, Thomas JonesAbstract:In 2012, brown bullhead (Ameiurus nebulosus) with large, raised, black growths were first reported from multiple areas within the Vermont portion of Lake Memphremagog. Subsequent surveys conducted from 2014 to 2017 at two sites within the lake indicated a prevalence of 30% in adult brown bullhead 200 mm and above total length. These lesions ranged from slightly raised smooth black areas to large nodular areas on the body surface and fins and within the oral cavity. Microscopically, these lesions were determined to be malignant melanoma with invasion into surrounding hypodermis, skeletal muscle and bone as well as metastases to gill, ovary and intestine. Liver neoplasms were also observed in 8% of the bullhead collected from Lake Memphremagog in 2015. Neither skin nor liver neoplasms were noted in Ticklenaked Pond, a site used for comparison.
Joel C. Trexler - One of the best experts on this subject based on the ideXlab platform.
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New polymorphic microsatellite loci in two fish species: bluefin killifish (Lucania goodei) and yellow bullhead (Ameiurus natalis)
Molecular Ecology Notes, 2006Co-Authors: Douglas A. Creer, Joel C. TrexlerAbstract:We identified four new polymorphic microsatellite loci in bluefin killifish (Lucania goodei) and five loci in yellow bullheads (Ameiurus natalis). We screened 400 killifish from 20 populations and 180 bullheads from nine populations, finding a high degree of polymorphism (nine to 54 alleles per locus; average expected heterozygosity 0.678–0.976). We found no evidence for linkage disequilibrium. Three of the loci found in bluefin killifish show heterozygote deficiency; the other loci do not deviate from Hardy–Weinberg expectations.
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effectiveness of airboat electrofishing for sampling fishes in shallow vegetated habitats
North American Journal of Fisheries Management, 1999Co-Authors: John H Chick, Sean Coyne, Joel C. TrexlerAbstract:Abstract We evaluated the effectiveness of airboat electrofishing for sampling large fishes (standard length, SL ≥8 cm) in shallow, vegetated habitats. Concurrent block-netting (0.1 ha) and airboat electrofishing were conducted at 11 sites in freshwater marshes of the Florida Everglades. We found significant positive relationships between log-transformed electrofishing catch per unit effort (CPUE) and both fish density (number/0.1 ha) and biomass (grams dry weight/0.1 ha) estimates from block nets. Analysis of covariance revealed that estimates of species richness were similar for electrofishing and block-net samples after accounting for differences in the total number of individuals sampled. Nevertheless, length-frequency and species-composition data differed between airboat electrofishing and block-net samples. Relative abundance of yellow bullheads Ameiurus natalis, Seminole killifish Fundulus seminolis, sunfishes (Lepomis spp.), and small size-classes of all species, were lower for electrofishing than...
Ján Koščo - One of the best experts on this subject based on the ideXlab platform.
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Ameiurus melas (black bullhead): morphological characteristics of new introduced species and its comparison with Ameiurus nebulosus (brown bullhead)
Reviews in Fish Biology and Fisheries, 2013Co-Authors: Jitka Rutkayová, Roman Biskup, Radovan Harant, Vlastimil Šlechta, Ján KoščoAbstract:In the present study we examined and compared external morphology as well as osteological characters of two species of the genus Ameiurus (Teleostei, Ictaluridae): the black bullhead ( Ameiurus melas ) and brown bullhead ( Ameiurus nebulosus ), two catfish species that are invasive to Europe. In total 83 (53 and 30) individuals were captured in the Czech Republic and the Slovak Republic and further analysed. For genetic screening of both Ameiurus species were chosen three DNA regions: part of nuclear Recombination activating gene 1 ( RAG - 1 ), mitochondrial gene for cytochrome b ( cyt b ) and mitochondrial sequence which includes 12S and 16S ribosomal RNA genes. The results presented in this paper concern specific osteological characteristics (original scheme of pectoral spine and pectoral girdle) used for the determination purposes and also verification that mathematical multivariate methods for external morphology analysis can be used for the determination of Ameiurus species. The summary of 80 out of 83 fish (96.4 %) was correctly classified using the discriminant analysis.
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When did the black bullhead, Ameiurus melas (Teleostei: Ictaluridae), arrive in Poland?
Archives of Polish Fisheries, 2010Co-Authors: Michał Nowak, Ján Koščo, P. Szczerbik, Dominika Mierzwa, Włodzimierz PopekAbstract:One specimen of the non-native ictalurid catfish the black bullhead, Ameiurus melas, was found in the collection of the Museum and Institute of Zoology of the Polish Academy of Sciences in Warsaw, Poland. This finding strongly supports the hypothesis that the black bullhead was co-introduced into Polish waters with the brown bullhead, Ameiurus nebulosus, at the end of the nineteenth century. The species might be distributed widely throughout Poland, thus careful investigation on the identity of the ictalurid catfish population throughout the country should be carried out.
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First record of the black bullhead Ameiurus melas (Teleostei: Ictaluridae) in Poland.
Journal of fish biology, 2010Co-Authors: Michał Nowak, Ján Koščo, Włodzimierz Popek, P. EplerAbstract:The North American catfish, the black bullhead Ameiurus melas, is recorded for the first time in Poland. The origin of these fish is not clear, but their presence may be associated with unregulated introductions by anglers.