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Rex A Dunham - One of the best experts on this subject based on the ideXlab platform.
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the effect of luteinizing hormone releasing hormone analog regime and stage of oocyte maturity for induced ovulation of channel catfish Ictalurus punctatus
Journal of The World Aquaculture Society, 2011Co-Authors: Nagaraj G Chatakondi, Anang Hari Kristanto, Roger D Yant, Gloria Umalimaceina, Rex A DunhamAbstract:This study addresses rapid methods to identify mature channel catfish, Ictalurus punctatus, females for induced spawning with luteinizing hormone releasing hormone analog (LHRHa) and common carp pituitary extract (CPE) and the effects of stage of maturity, hormone dose, season, and cannulation before hormone injection. Hormonal intervention is the most effective method for inducing maturation and spawning in channel catfish × blue catfish, Ictalurus furcatus, hybrids. A total of 80 mature channel catfish were staged for maturity based on secondary sexual characteristics and 20–30 oocytes cannulated to ascertain their maturation stage based on the position of gonadal vesicle. Twenty females were randomly assigned to one of the four hormone regimes (priming + resolving dose): CPE 2 + 8 mg/kg (CPEC); LHRHa 20 + 40 µg/kg (LHRHaL); LHRHa 20 + 60 µg/kg (LHRHaM); and LHRHa 20 + 80 µg/kg (LHRHaH) and a fifth treatment consisted of 20 females selected based on apparent maturity as evidenced by external appearance were injected with CPE, 2 + 8 mg/kg without cannulation (CPEO). Two trials were conducted in early part of the spawning season and two trials in peak season. External methods to identify maturity correlated (r = 0.63) with that of “germinal vesicle position” method to identify the stage of maturity in females. Mean percent of females that ovulated, hatched, and fry produced per kg body weight did not differ (P > 0.05) among the five hormone treatments. The mean percent females that ovulated was higher (P 0.05) with that of non-cannulated catfish. The mean egg quality of hormone-induced females and percent of females ovulated in response to hormone treatment established a weak but significant linear relationship (Y = 3.85 + 0.008 × ovulation, r2 = 0.39, P < 0.05).
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microarray analysis of gene expression in the blue catfish liver reveals early activation of the mhc class i pathway after infection with edwardsiella ictaluri
Molecular Immunology, 2008Co-Authors: Jeffery S Terhune, Huseyin Kucuktas, Shaolin Wang, Samiran Nandi, Benjaporn Somridhivej, Rex A DunhamAbstract:The acute nature of disease outbreaks in aquaculture settings has served to emphasize the importance of the innate immune response of fish for survival and led to the recent identification and characterization of many of its components. Catfish, the predominant aquaculture species in the United States, is an important model for the study of the teleost immune system. However, transcriptomic-level studies of disease-related gene expression in catfish have only recently been initiated, and understanding of immune responses to pathogen infections is limited. Here, we have developed and utilized a 28K in situ oligonucleotide microarray composed of blue catfish (Ictalurus furcatus) and channel catfish (Ictalurus punctatus) transcripts. While channel catfish accounts for the majority of commercial production, the closely related blue catfish possesses several economically important phenotypic traits. Microarray analysis of gene expression changes in blue catfish liver after infection with Gram-negative bacterium Edwardsiella ictaluri indicated the strong upregulation of several pathways involved in the inflammatory immune response and potentially in innate disease resistance. A multifaceted response to infection could be observed, encompassing the complement cascade, iron regulation, inflammatory cell signaling, and antigen processing and presentation. The induction of several components of the MHC class I-related pathway following infection with an intracellular bacterium is reported here for the first time in fish. A comparison with previously published expression profiles in the channel catfish liver was also made and the microarray results extended by use of quantitative RT-PCR. Our results add to the understanding of the teleost immune responses and provide a solid foundation for future functional characterization, genetic mapping, and QTL analysis of immunity-related genes from catfish.
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dress out and fillet yields of channel catfish Ictalurus punctatus blue catfish Ictalurus furcatus and their f1 f2 and backcross hybrids
Aquaculture, 2003Co-Authors: Brad J Argue, Rex A DunhamAbstract:Abstract The channel catfish, Ictalurus punctatus, ♀×blue catfish, Ictalurus furcatus, ♂ F1 hybrid showed increased processing yields over the most commonly cultured catfish, channel catfish, in the US. The F1 hybrid had higher dress-out and fillet percentage (61.1% and 45.7%, respectively) than channel catfish (57.5%, 42.5%), blue catfish (58.9%, 44.4%), F2 hybrid catfish (57.3%, 42.5%), F1×channel catfish (57.3%, 42.7%), F1×blue catfish (58.3%, 42.4%), blue catfish×F1 (58.2%, 43.2%), and channel catfish×F1 (56.8%, 42.1%). Individual heterosis had a strong positive effect on dress-out and fillet percentage. Channel catfish additive genetic effects had a strong negative effect on dress-out and fillet percentage. Females had greater dress-out (58.4% to 57.9%) and fillet percentage (43.6% to 43.0%) than males (P
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enhanced bacterial disease resistance of transgenic channel catfish Ictalurus punctatus possessing cecropin genes
Marine Biotechnology, 2002Co-Authors: Rex A Dunham, Gregory W Warr, Amy Nichols, Patricia L Duncan, Brad J Argue, Darlene L Middleton, Huseyin KucuktasAbstract:The cecropin B gene from the moth Hyalophora cecropia, driven by the cytomegalovirus promoter, was transferred to the channel catfish Ictalurus punctatus. Transgenic individuals (P1) were mated to produce individuals (F1) that exhibited enhanced disease resistance and survival when challenged with pathogenic bacteria. During the epizootic of Flavobacterium columnare in an earthen pond, the percentage of transgenic individuals containing preprocecropin B construct that survived (100%) was significantly greater (P 0.05). Inheritance of the transgene by the F1 generation, 20.2% to 30.7% was typical of that in studies with transgenic channel catfish.
Huseyin Kucuktas - One of the best experts on this subject based on the ideXlab platform.
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identification and characterization of full length cdnas in channel catfish Ictalurus punctatus and blue catfish Ictalurus furcatus
PLOS ONE, 2010Co-Authors: Shikai Liu, Shaolin Wang, Jason Abernathy, Eric Peatman, Fei Chen, Yoona Lee, Yanliang Jiang, Hong Liu, Huseyin KucuktasAbstract:United States Department of Agriculture National Institute for Food and Agriculture Animal Genome Basic Genome Reagents and Tools Program [2009-35205-05101]; Korean Government (MOEHRD) [KRF-2008-357-F00035]
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microarray analysis of gene expression in the blue catfish liver reveals early activation of the mhc class i pathway after infection with edwardsiella ictaluri
Molecular Immunology, 2008Co-Authors: Jeffery S Terhune, Huseyin Kucuktas, Shaolin Wang, Samiran Nandi, Benjaporn Somridhivej, Rex A DunhamAbstract:The acute nature of disease outbreaks in aquaculture settings has served to emphasize the importance of the innate immune response of fish for survival and led to the recent identification and characterization of many of its components. Catfish, the predominant aquaculture species in the United States, is an important model for the study of the teleost immune system. However, transcriptomic-level studies of disease-related gene expression in catfish have only recently been initiated, and understanding of immune responses to pathogen infections is limited. Here, we have developed and utilized a 28K in situ oligonucleotide microarray composed of blue catfish (Ictalurus furcatus) and channel catfish (Ictalurus punctatus) transcripts. While channel catfish accounts for the majority of commercial production, the closely related blue catfish possesses several economically important phenotypic traits. Microarray analysis of gene expression changes in blue catfish liver after infection with Gram-negative bacterium Edwardsiella ictaluri indicated the strong upregulation of several pathways involved in the inflammatory immune response and potentially in innate disease resistance. A multifaceted response to infection could be observed, encompassing the complement cascade, iron regulation, inflammatory cell signaling, and antigen processing and presentation. The induction of several components of the MHC class I-related pathway following infection with an intracellular bacterium is reported here for the first time in fish. A comparison with previously published expression profiles in the channel catfish liver was also made and the microarray results extended by use of quantitative RT-PCR. Our results add to the understanding of the teleost immune responses and provide a solid foundation for future functional characterization, genetic mapping, and QTL analysis of immunity-related genes from catfish.
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enhanced bacterial disease resistance of transgenic channel catfish Ictalurus punctatus possessing cecropin genes
Marine Biotechnology, 2002Co-Authors: Rex A Dunham, Gregory W Warr, Amy Nichols, Patricia L Duncan, Brad J Argue, Darlene L Middleton, Huseyin KucuktasAbstract:The cecropin B gene from the moth Hyalophora cecropia, driven by the cytomegalovirus promoter, was transferred to the channel catfish Ictalurus punctatus. Transgenic individuals (P1) were mated to produce individuals (F1) that exhibited enhanced disease resistance and survival when challenged with pathogenic bacteria. During the epizootic of Flavobacterium columnare in an earthen pond, the percentage of transgenic individuals containing preprocecropin B construct that survived (100%) was significantly greater (P 0.05). Inheritance of the transgene by the F1 generation, 20.2% to 30.7% was typical of that in studies with transgenic channel catfish.
Phillip H Klesius - One of the best experts on this subject based on the ideXlab platform.
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susceptibility of channel catfish blue catfish and channel blue catfish hybrid to ichthyophthirius multifiliis
Aquaculture, 2011Co-Authors: Dehai Xu, Phillip H KlesiusAbstract:Abstract Information on the infectivity of Ichthyophthirius multifiliis (Ich), a severe fish parasite that causes high mortality, is limited for blue catfish ( Ictalurus furcatus ) and catfish hybrids (CB hybrid) resulting from female channel catfish ( Ictalurus punctatus ) × male blue catfish crosses. The objective of this study was to compare channel catfish, blue catfish and CB hybrids on the infection level and fish mortality caused by Ich using a cohabitation model. To compare the susceptibility to Ich between channel and blue catfish, fish were exposed to 5000 or 10000 theronts per fish, respectively. There were no statistical differences in the infection levels and mortalities between channel catfish and blue catfish. Channel catfish showed an infection score of 2.9 and blue catfish of 2.7 when infected by theronts at 10,000 theronts per fish. The cumulative mortalities were 86.3% and 80.6 %, respectively for channel catfish and blue catfish when exposed to theronts at 5000 theronts per fish. To compare the susceptibility to Ich between channel catfish and CB hybrid, fish were infected by cohabiting with 1 or 3 Ich-infected fish or exposure to Ich theronts at 2500–10,000 theronts per fish. Channel catfish and CB hybrid showed similar infection levels of > 150 trophonts/fish and infection duration of 7–8 days when cohabited with 1 or 3 Ich-infected fish. All channel catfish and CB hybrid exposed to theronts at the dose of 10,000 theronts/fish showed heavy infection of > 150 trophonts/fish. The cumulative mortalities were 90% and 80% for channel catfish and CB hybrid after exposure to 2500 theronts per fish. No statistical difference was found in the infection levels and mortalities using two infection methods between channel catfish and CB hybrid. Overall results indicated that CB hybrid were as susceptible to Ich as channel catfish or blue catfish.
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non infectivity of cattle streptococcus agalactiae in nile tilapia oreochromis niloticus and channel catfish Ictalurus punctatus
Aquaculture, 2008Co-Authors: Julio C Garcia, Phillip H Klesius, Joyce J. Evans, Craig A ShoemakerAbstract:Abstract Streptococcus agalactiae is classified as a Lancefield's group B Streptococcus . It is one causative bacterium of streptococcosis that is responsible for severe economic losses in wild and cultured fish worldwide. S. agalactiae also causes bovine mastitis. No information is available on infectivity of cattle S. agalactiae isolates in fish. In the present study, the results showed that 10 cattle isolates from 8 different dairy farms were not infectious in Nile tilapia ( Oreochromis niloticus ) or channel catfish ( Ictalurus punctatus ) at greater than 10 8 colony forming units per fish. S. agalactiae was not re-isolated from the brain or head kidney of the fish at 24 and 48 h post-injection .
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Isolation and characterization of strains of Flavobacterium columnare from Brazil.
Journal of fish diseases, 2005Co-Authors: Henrique César Pereira Figueiredo, Phillip H Klesius, Craig A Shoemaker, Covadonga R. Arias, Joyce J. Evans, D J Pereira, M T D PeixotoAbstract:Flavobacterium columnare is an important pathogen of freshwater fish, implicated in skin and gill disease, often causing high mortality. An outbreak of skin disease in fingerling and adult Nile tilapia, Oreochromis niloticus (L.), cultivated in a recirculation system, was investigated. Four strains were isolated and characterized by biochemical reactions, enzyme production, fatty acid profile and analysis of the 16S-23S rDNA intergenic spacer region. All strains were identified as F. columnare. Experimental infection assays with one of these strains (BZ-5-02) were conducted and pathogenicity (by intramuscular route) was demonstrated in Nile tilapia and channel catfish, Ictalurus punctatus (Rafinesque). This is the first report of characterization of Brazilian strains of F. columnare.
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efficacy of a modified live edwardsiella ictaluri vaccine in channel catfish as young as seven days post hatch
Aquaculture, 1999Co-Authors: Craig A Shoemaker, Phillip H Klesius, Joseph M BrickerAbstract:Channel catfish (Ictalurus punctatus) were vaccinated by immersion at 12, 14, 16 and 31 days post hatch with modified live Edwardsiella ictaluri RE-33 vaccine in 1997 and 7 and 10 days post hatch in 1998. At 20 to 21 days post vaccination, the groups of vaccinates and non-vaccinates were challenged with virulent E. ictaluri and monitored for mortality for at least 14 days following challenge. Results showed the vaccine to be efficacious in channel catfish as young as 7 days post hatch with relative percent survival ranging from 58.4 to 77.5.
Roy Curtiss - One of the best experts on this subject based on the ideXlab platform.
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fur regulated iron uptake system of edwardsiella ictaluri and its influence on pathogenesis and immunogenicity in the catfish host
Infection and Immunity, 2012Co-Authors: Javier Santander, Greg Golden, Sooyoung Wanda, Roy CurtissAbstract:The ability of bacterial pathogens to take up iron from the host during infection is necessary for their multiplication within the host. However, host high-affinity iron binding proteins limit levels of free iron in fluids and tissues. To overcome this deficiency of iron during infection, bacterial pathogens have developed iron uptake systems that are upregulated in the absence of iron, typically tightly controlled by the ferric uptake regulator (Fur) protein. The iron uptake system of Edwardsiella ictaluri, a host-restricted pathogen of channel catfish (Ictalurus punctatus) and the main pathogen of this fish in aquaculture, is unknown. Here we describe the E. ictaluri Fur protein, the iron uptake machinery controlled by Fur, and the effects of fur gene deletion on virulence and immunogenicity in the fish host. Analysis of the E. ictaluri Fur protein shows that it lacks the N-terminal region found in the majority of pathogen-encoded Fur proteins. However, it is fully functional in regulated genes encoding iron uptake proteins. E. ictaluri grown under iron-limited conditions upregulates an outer membrane protein (HemR) that shows heme-hemoglobin transport activity and is tightly regulated by Fur. In vivo studies showed that an E. ictaluri Δfur mutant is attenuated and immune protective in zebrafish (Danio rerio) and catfish (Ictalurus punctatus), triggering systemic immunity. We conclude that an E. ictaluri Δfur mutant could be an effective component of an immersion-oral vaccine for the catfish industry.
Fei Chen - One of the best experts on this subject based on the ideXlab platform.
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identification and characterization of full length cdnas in channel catfish Ictalurus punctatus and blue catfish Ictalurus furcatus
PLOS ONE, 2010Co-Authors: Shikai Liu, Shaolin Wang, Jason Abernathy, Eric Peatman, Fei Chen, Yoona Lee, Yanliang Jiang, Hong Liu, Huseyin KucuktasAbstract:United States Department of Agriculture National Institute for Food and Agriculture Animal Genome Basic Genome Reagents and Tools Program [2009-35205-05101]; Korean Government (MOEHRD) [KRF-2008-357-F00035]
