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Clive M. Jones - One of the best experts on this subject based on the ideXlab platform.
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assessment of stocking size and density in the production of redclaw crayfish cherax quadricarinatus von martens decapoda Parastacidae cultured under earthen pond conditions
Aquaculture, 2000Co-Authors: Clive M. Jones, Ian M RuscoeAbstract:Abstract Redclaw crayfish, Cherax quadricarinatus (von Martens) (Decapoda: Parastacidae),were cultured for 140 days within 24 net pens in a 0.2-ha earthen pond at densities of 3, 9 and 15 m−2, with mean stocking sizes of either 4.71 g or 16.89 g. Crayfish were fed a formulated supplemental pellet diet. An economic evaluation accounted for price paid per individual at stocking, value of the individual at harvest, and amount of food fed. There was no significant effect of density or stocking size on survival that ranged from 76.6% to 87.5%. As density increased, significant decreases in mean harvest size and specific growth rate occurred for both stocking sizes. Mean food quotients (FQs), yields, and economic returns significantly increased as stocking size and density increased, with large-stocked animals at 15 m−2 having the highest FQ, yield and economic return. This experiment shows that when stocking with well-advanced juveniles at densities between 9 and 15 m−2, yields in excess of 5 t ha are achievable in 140 days of culture.
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A review of genetic improvement in growth rate in redclaw crayfish Cherax quadricarinatus (von Martens) (Decapoda: Parastacidae)
Aquaculture Research, 2000Co-Authors: Clive M. Jones, C.p. Mcphee, Ian M RuscoeAbstract:This paper provides a review and summary of strain comparison and selective breeding work carried out on redclaw crayfish Cherax quadricarinatus (von Martens) at the Queensland Department of Primary Industries, Freshwater Fisheries and Aquaculture Centre, Walkamin. Redclaw crayfish are a highly marketable, environmentally tolerant, freshwater crayfish with a moderately fast, but variable, growth rate. Five strains of the species were assessed morphologically and in terms of age at maturity. A non-replicated production trial was also carried out before two strains, from the Gilbert and Flinders rivers in North Queensland, were chosen to be part of an experimental selective breeding programme for improved growth. Initially, 14 families of each strain were randomly mated and grown out. At this point, a size-related selection took place, with the largest animals from each family forming a selected line, and individuals from around the mean forming a control line. Within-family selection and reciprocal mating between families was performed. Data were collected after each of two generations of growout and analysed by analysis of variance. Significant differences (P
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a review of genetic improvement in growth rate in redclaw crayfish cherax quadricarinatus von martens decapoda Parastacidae
Aquaculture Research, 2000Co-Authors: Clive M. Jones, C.p. Mcphee, Ian M RuscoeAbstract:This paper provides a review and summary of strain comparison and selective breeding work carried out on redclaw crayfish Cherax quadricarinatus (von Martens) at the Queensland Department of Primary Industries, Freshwater Fisheries and Aquaculture Centre, Walkamin. Redclaw crayfish are a highly marketable, environmentally tolerant, freshwater crayfish with a moderately fast, but variable, growth rate. Five strains of the species were assessed morphologically and in terms of age at maturity. A non-replicated production trial was also carried out before two strains, from the Gilbert and Flinders rivers in North Queensland, were chosen to be part of an experimental selective breeding programme for improved growth. Initially, 14 families of each strain were randomly mated and grown out. At this point, a size-related selection took place, with the largest animals from each family forming a selected line, and individuals from around the mean forming a control line. Within-family selection and reciprocal mating between families was performed. Data were collected after each of two generations of growout and analysed by analysis of variance. Significant differences (P < 0.05) were measured between strains, sexes and between selected and control lines. Selected individuals grew 9.5% faster than the controls. Recommendations for selective breeding research involving freshwater crayfish are presented.
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production of juvenile redclaw crayfish cherax quadricarinatus von martens decapoda Parastacidae ii juvenile nutrition and habitat
Aquaculture, 1995Co-Authors: Clive M. JonesAbstract:Newly hatched redclaw crayfish Cherax quadricarinatus were reared for 39 days in aquaria using various combinations of food and habitat. Food treatments were fresh zooplankton and a high protein formulated flake diet. Habitat treatments involved the presence/absence of a floating aquatic macrophyte, Pistia stratiodes. Both survival and growth of juveniles were significantly influenced by the type of food and habitat. Fresh zooplankton produced the best growth. An interactive effect between food type and Pistia resulted in differential survival. Use of aquatic macrophytes for habitat in intensive juvenile production systems is not recommended.
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production of juvenile redclaw crayfish cherax quadricarinatus von martens decapoda Parastacidae iii managed pond production trials
Aquaculture, 1995Co-Authors: Clive M. JonesAbstract:Abstract Commercial-scale production of juvenile redclaw crayfish was conducted in earthen ponds. Based upon the results of previous experimental studies in tanks and aquaria, earthen ponds (1300 and 2600 m2) were furnished with juvenile crayfish shelters, and were prepared and managed to maximise availability of zooplankton. Juvenile redclaw were introduced by stocking ponds with egg-bearing females. Stocking density, as expressed by number of fertile eggs introduced, ranged from 74 to 326/ m2. Ponds were harvested after culture periods ranging from 45 to 62 days. Juvenile number at harvest ranged from around 6000 to over 36 000, representing a mean of 63.2 juveniles per maternal survivor. Mean size at harvest ranged from 0.31 to 1.00 g, representing growth of 9.7 to 36.9 mg/day. Results suggest that managed pond production of juvenile redclaw is commercially viable at the production rates achieved, and that a considerable increase in productivity is possible with increased availability of shelter and improved zooplankton management techniques.
Christopher M Austin - One of the best experts on this subject based on the ideXlab platform.
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more evolution underground accelerated mitochondrial substitution rate in australian burrowing freshwater crayfishes decapoda Parastacidae
Molecular Phylogenetics and Evolution, 2018Co-Authors: Christopher M Austin, Han Ming Gan, Mun Hua Tan, Yin Peng Lee, Mark B Schultz, Pierre Horwitz, Quinton BurnhamAbstract:Abstract To further understand the evolutionary history and mitogenomic features of Australia’s highly distinctive freshwater crayfish fauna, we utilized a recently described rapid mitogenome sequencing pipeline to generate 24 new crayfish mitogenomes including a diversity of burrowing crayfish species and the first for Astacopsis gouldi, the world’s largest freshwater invertebrate. Whole mitogenome-based phylogeny estimates using both Bayesian and Maximum Likelihood methods substantially strengthen existing hypotheses for systematic relationships among Australian freshwater crayfish with evidence of pervasive diversifying selection and accelerated mitochondrial substitution rate among the members of the clade representing strongly burrowing crayfish that may reflect selection pressures for increased energy requirement for adaptation to terrestrial environment and a burrowing lifestyle. Further, gene rearrangements are prevalent in the burrowing crayfish mitogenomes involving both tRNA and protein coding genes. In addition, duplicated control regions were observed in two closely related Engaeus species, together with evidence for concerted evolution. This study significantly adds to the understanding of Australian freshwater crayfish evolutionary relationships and suggests a link between mitogenome evolution and adaptation to terrestrial environments and a burrowing lifestyle in freshwater crayfish.
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the complete mitogenome of the red claw crayfish cherax quadricarinatus von martens 1868 crustacea decapoda Parastacidae
Mitochondrial DNA, 2016Co-Authors: Christopher M AustinAbstract:The commercial freshwater crayfish Cherax quadricarinatus complete mitochondrial genome was recovered from partial genome sequencing using the MiSeq Personal Sequencer. The mitogenome has 15,869 base pairs consisting of 13 protein-coding genes, 2 ribosomal subunit genes, 22 transfer RNAs, and a non-coding AT-rich region. The base composition of C. quadricarinatus is 32.16% for T, 23.39% for C, 33.26% for A, and 11.19% for G, with an AT bias of 65.42%.
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first comprehensive multi tissue transcriptome of cherax quadricarinatus decapoda Parastacidae reveals unexpected diversity of endogenous cellulase
Organisms Diversity & Evolution, 2016Co-Authors: Larry J Croft, Adam D. Miller, Mark B Schultz, Christopher M AustinAbstract:The Australian freshwater crayfish species, Cherax quadricarinatus Von Martens, 1868, is an important commercial and invasive species that is also being increasingly used as a model organism to address important and interesting questions in crustacean biology. Through deep sequencing of the transcriptome of C. quadricarinatus from the hepatopancreas and four other tissues, we examine the evolution of endogenously transcribed cellulase genes and provide new insights into controversial issues regarding the nutritional biology of crayfishes. A cluster assembly approach yielded one of the highest quality transcriptome assemblies for a decapod crustacean to date. A total of 206,341,872 reads with an average read length of 80 bp were generated from sequencing the transcriptomes from the heart, kidney, hepatopancreas, nerve, and testis tissues. The assembled transcriptome contains a total of 44,525 transcripts. A total of 65 transcripts coding for carbohydrate-active enzymes (CAZy) were identified based on hidden Markov model (HMM), and a majority of them display high relative transcript abundance in the hepatopancreas tissue, supporting their role in nutrient digestion. Comprehensive phylogenetic analyses of proteins belonging to two main glycosyl hydrolase families (GH9 and GH5) suggest shared ancestry of C. quadricarinatus cellulases with other characterized crustacean cellulases. Our study significantly expands the number of known crustacean-derived CAZy-coding transcripts. More importantly, the surprising level of evolutionary diversification of these proteins in C. quadricarinatus suggests that these enzymes may have been of critical importance in the adaptation of freshwater crayfishes to new plant-based food sources as part of their successful invasion of freshwater systems from marine ancestors.
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the complete mitogenome of cherax monticola crustacea decapoda Parastacidae a large highland crayfish from new guinea
Mitochondrial DNA, 2016Co-Authors: Han Ming Gan, Mun Hua Tan, Rury Eprilurahman, Christopher M AustinAbstract:The complete mitochondrial genome of a highland freshwater crayfish, Cherax monticola, was recovered by shotgun sequencing. The mitogenome consists of 15,917 base pairs containing 13 protein-coding genes, 2 ribosomal subunit genes, 22 transfer RNAs and a non-coding AT-rich region. The base composition of C. monticola is 33.46% for T, 21.48% for C, 33.71% for A and 11.35% for G, with an AT bias of 67.17%.
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Complete mitochondrial DNA sequence of the Australian freshwater crayfish, Cherax destructor (Crustacea: Decapoda: Parastacidae): a novel gene order revealed.
Gene, 2004Co-Authors: Adam D. Miller, Thuy T T Nguyen, Christopher P. Burridge, Christopher M AustinAbstract:The complete mitochondrial DNA sequence was determined for the Australian freshwater crayfish Cherax destructor (Crustacea: Decapoda: Parastacidae). The 15,895-bp genome is circular with the same gene composition as that found in other metazoans. However, we report a novel gene arrangement with respect to the putative arthropod ancestral gene order and all other arthropod mitochondrial genomes sequenced to date. It is apparent that 11 genes have been translocated (ND1, ND4, ND4L, Cyt b, srRNA, and tRNAs Ser(UGA), Leu(CUN), Ile, Cys, Pro, and Val), two of which have also undergone inversions (tRNAs Pro and Val). The 'duplication/random loss' mechanism is a plausible model for the observed translocations, while 'intramitochondrial recombination' may account for the gene inversions. In addition, the arrangement of rRNA genes is incompatible with current mitochondrial transcription models, and suggests that a different transcription mechanism may operate in C. destructor.
Laura Lopez S Greco - One of the best experts on this subject based on the ideXlab platform.
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effect of food restriction on female reproductive performance in the redclaw crayfish cherax quadricarinatus Parastacidae decapoda
Aquaculture Research, 2017Co-Authors: Fernando Diaz, Carolina Tropea, Liane Stumpf, Laura Lopez S GrecoAbstract:Fil: Castillo Diaz, Fernando. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Ciudad Universitaria. Instituto de Biodiversidad y Biologia Experimental y Aplicada. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Biodiversidad y Biologia Experimental y Aplicada; Argentina
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sperm production in the red claw crayfish cherax quadricarinatus decapoda Parastacidae
Aquaculture, 2009Co-Authors: Ana B Bugnot, Laura Lopez S GrecoAbstract:Abstract The objective of this study is to evaluate the effect of body size, temperature and annual cycle on sperm production in Cherax quadricarinatus . Sperm count and sperm mortality were estimated, the reproductive system was weighted, and macro and microscopical analysis of the testes and vasa deferentia were conducted. Sperm count and weight of the reproductive system are strongly related to male size, in contrast to sperm mortality. The spermatophore structure presented macro and microscopical differences between sizes. Males higher in size have more adherent spermatophores. This species has a reproductive cycle related to sperm production. Sperm count and weight of the vasa deferentia rise in summer, while the weight of the testes increases in winter. During the spring, the sperm cord presents a higher density than in other seasons. The temperature seems to affect sperm production being 27 and 29 °C the best assayed conditions. The present results are relevant information to obtain the best sperm viability selecting male size, season of sampling and the best temperature for the reproductive stock and future assays of spermatophore cryopreservation for this species aquaculture.
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development of the female reproductive system in the freshwater crayfish cherax quadricarinatus decapoda Parastacidae
Invertebrate Biology, 2008Co-Authors: Fernanda J Vazquez, Carolina Tropea, Laura Lopez S GrecoAbstract:. The differentiation of the female reproductive system from a macroscopic and microscopic point of view was studied in Cherax quadricarinatus. For this characterization, 184 females were dissected and processed for the histological analysis. From the differentiation of the ovary up to its maturity, three ovarian morphotypes could be distinguished macroscopically: parallel strands without any contact between them, an H-shaped ovary, and a Y-shaped ovary. These morphotypes were compared within the Astacida. Four ovarian developmental stages were recognized based on ovary color, and the histological structure and relative proportion of cellular types. The post-spawning ovary was also characterized. The components of the female reproductive system sheath were described and its modifications in the ovary and oviducts were determined and compared. Theoretical aspects of the study of sexual differentiation in C. quadricarinatus were discussed within a phylogenetic framework.
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structural changes in the spermatophore of the freshwater red claw crayfish cherax quadricarinatus von martens 1898 decapoda Parastacidae
Acta Zoologica, 2007Co-Authors: Laura Lopez S Greco, Fabiana Lo L NostroAbstract:Lopez Greco, L.S. and Lo Nostro, F.L. 2007. Structural changes in the spermatophore of the freshwater ‘red claw’ crayfish Cherax quadricarinatus (Von Martens, 1898) (Decapoda, Parastacidae). —Acta Zoologica (Stockholm) 88: 000–000 The structure of the spermatophore was studied in Cherax quadricarinatus. Pieces of the distal vas deferens and transferred spermatophore from the females were fixed, cut and stained. Within the distal vas deferens, the primary layer and the secondary layer of the spermatophore were distinguishable. In the latter, two components were detected: cytoplasmic droplets and a homogeneous matrix. During the first 10 minutes post-extrusion the cytoplasmic droplets drastically changed from looking like ‘empty droplets’; at this time the spermatophore changed from a liquid stage to a sticky one. One hour after extrusion the spermatophore began to harden and within the first 24–48 h post-mating it was a solid and intense white structure tightly attached to the female; after 72 h it acquired a softer aspect, completely dehiscing between 96 and 120 h post-mating. Histologically, the primary layer maintained its integrity surrounding the spermatozoa while the secondary layer lost the cytoplasmic droplets. The spermatophore began to hydrate between 24 and 48 h and by 72–96 h many sections of the sperm cord began to coalesce. From 48 h post-mating some fissures appeared within the matrix that enlarged between 72 and 120 h. We propose that both manipulation by the female and hydration are the mechanisms involved in the release of the spermatozoa from the spermatophore.
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morphology of the male reproductive system and spermatophore formation in the freshwater red claw crayfish cherax quadricarinatus von martens 1898 decapoda Parastacidae
Acta Zoologica, 2007Co-Authors: Laura Lopez S Greco, Fernanda J Vazquez, E M RodriguezAbstract:Lopez Greco, L.S., Vazquez, F. and Rodriguez, E.M. 2007. Sperm production and spermatophore formation in the freshwater ‘red claw’ crayfish Cherax quadricarinatus (Von Martens 1898) (Decapoda, Parastacidae). — Acta Zoologica (Stockholm) 88 : 223‐229. The morphology of the male reproductive system was studied in Cherax quadricarinatus . The testes and vasa deferentia were dissected, fixed, cut and stained. Testes appear as two parallel and opalescent strands; they present many testicular lobes, each lobe containing cells in the same stage of the spermatogenic cycle. A vas deferens arises from the external side of each testis and three parts were clearly distinguished: proximal vas deferens (PVD), middle vas deferens (MVD) and distal vas deferens (DVD). The PVD is opalescent and highly convoluted, the MVD is pale white in colour and convoluted, but wider in diameter than the PVD, while the DVD shows the widest diameter, is straight and is white in colour. A single-layered epithelium is recognized in the vas deferens; with cylindrical cells in the PVD and cuboid cells in the MVD and DVD. The formation of the spermatophore starts at the PVD, while the secondary layer of the spermatophore seems to be added at the MVD. At the DVD, the highly coiled spermatophore is surrounded by the periodic acid Schiff-positive sticky components of the secondary layer. Many aspects of spermatophore formation in C. quadricarinatus differ from those of other Astacida. The applied aspects of this study for aquaculture purposes are discussed.
Ian M Ruscoe - One of the best experts on this subject based on the ideXlab platform.
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assessment of stocking size and density in the production of redclaw crayfish cherax quadricarinatus von martens decapoda Parastacidae cultured under earthen pond conditions
Aquaculture, 2000Co-Authors: Clive M. Jones, Ian M RuscoeAbstract:Abstract Redclaw crayfish, Cherax quadricarinatus (von Martens) (Decapoda: Parastacidae),were cultured for 140 days within 24 net pens in a 0.2-ha earthen pond at densities of 3, 9 and 15 m−2, with mean stocking sizes of either 4.71 g or 16.89 g. Crayfish were fed a formulated supplemental pellet diet. An economic evaluation accounted for price paid per individual at stocking, value of the individual at harvest, and amount of food fed. There was no significant effect of density or stocking size on survival that ranged from 76.6% to 87.5%. As density increased, significant decreases in mean harvest size and specific growth rate occurred for both stocking sizes. Mean food quotients (FQs), yields, and economic returns significantly increased as stocking size and density increased, with large-stocked animals at 15 m−2 having the highest FQ, yield and economic return. This experiment shows that when stocking with well-advanced juveniles at densities between 9 and 15 m−2, yields in excess of 5 t ha are achievable in 140 days of culture.
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A review of genetic improvement in growth rate in redclaw crayfish Cherax quadricarinatus (von Martens) (Decapoda: Parastacidae)
Aquaculture Research, 2000Co-Authors: Clive M. Jones, C.p. Mcphee, Ian M RuscoeAbstract:This paper provides a review and summary of strain comparison and selective breeding work carried out on redclaw crayfish Cherax quadricarinatus (von Martens) at the Queensland Department of Primary Industries, Freshwater Fisheries and Aquaculture Centre, Walkamin. Redclaw crayfish are a highly marketable, environmentally tolerant, freshwater crayfish with a moderately fast, but variable, growth rate. Five strains of the species were assessed morphologically and in terms of age at maturity. A non-replicated production trial was also carried out before two strains, from the Gilbert and Flinders rivers in North Queensland, were chosen to be part of an experimental selective breeding programme for improved growth. Initially, 14 families of each strain were randomly mated and grown out. At this point, a size-related selection took place, with the largest animals from each family forming a selected line, and individuals from around the mean forming a control line. Within-family selection and reciprocal mating between families was performed. Data were collected after each of two generations of growout and analysed by analysis of variance. Significant differences (P
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a review of genetic improvement in growth rate in redclaw crayfish cherax quadricarinatus von martens decapoda Parastacidae
Aquaculture Research, 2000Co-Authors: Clive M. Jones, C.p. Mcphee, Ian M RuscoeAbstract:This paper provides a review and summary of strain comparison and selective breeding work carried out on redclaw crayfish Cherax quadricarinatus (von Martens) at the Queensland Department of Primary Industries, Freshwater Fisheries and Aquaculture Centre, Walkamin. Redclaw crayfish are a highly marketable, environmentally tolerant, freshwater crayfish with a moderately fast, but variable, growth rate. Five strains of the species were assessed morphologically and in terms of age at maturity. A non-replicated production trial was also carried out before two strains, from the Gilbert and Flinders rivers in North Queensland, were chosen to be part of an experimental selective breeding programme for improved growth. Initially, 14 families of each strain were randomly mated and grown out. At this point, a size-related selection took place, with the largest animals from each family forming a selected line, and individuals from around the mean forming a control line. Within-family selection and reciprocal mating between families was performed. Data were collected after each of two generations of growout and analysed by analysis of variance. Significant differences (P < 0.05) were measured between strains, sexes and between selected and control lines. Selected individuals grew 9.5% faster than the controls. Recommendations for selective breeding research involving freshwater crayfish are presented.
Enrique M Rodriguez - One of the best experts on this subject based on the ideXlab platform.
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induction of somatic growth in juvenile crayfish cherax quadricarinatus decapoda Parastacidae by ecdysone and insulin growth factor
Aquaculture, 2012Co-Authors: Anouk Chaulet, D A Medesani, J Freitas, A Cervino, N Cervino, Enrique M RodriguezAbstract:Abstract The effect of ecdysone and IGF-1 on the somatic growth of juvenile crayfish Cherax quadricarinatus , was examined both in vitro and in vivo . After 24 h of incubating explants of abdominal muscle, protein synthesis was augmented by exposure to 0.15 μM of ecdysone, 0.02 μM of IGF-1 or the combination of both hormones. The in vivo experiments were done by feeding the juveniles a pellet food supplemented with ecdysone, IGF-1 or a combination of both hormones, at doses equivalents to those that had an effect in the in vitro experiment. Animals fed IGF-1 or IGF-1 and ecdysone enriched pellets showed a higher weight gain than controls, while no differences were detected in the case of juveniles fed pellets enriched with ecdysone alone. In close correspondence with these results, and also with the in vitro results, a significant increment in protein content was found in muscle of crayfish treated with IGF-1, alone or in combination with ecdysone. On the other hand, significant lower lipid content was found in the hepatopancreas of both groups treated with IGF-1. Our results confirm the in vivo anabolic effects of IGF-1 on crustaceans, in terms of enhancing growth and protein synthesis, therefore identifying this hormone as a potential tool for crayfish culture.
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Effects of Glyphosate and Polyoxyethylenamine on Growth and Energetic Reserves in the Freshwater Crayfish Cherax quadricarinatus (Decapoda, Parastacidae)
Archives of Environmental Contamination and Toxicology, 2011Co-Authors: Jimena L. Frontera, Anouk Chaulet, Itzick Vatnick, Enrique M RodriguezAbstract:Freshwater crayfish Cherax quadricarinatus have a high commercial value and are cultured in farms where they are potentially exposed to pesticides. Therefore, we examined the sublethal effects of a 50-day exposure to glyphosate acid and polyoxyethylenamine (POEA), both alone and in a 3:1 mixture, on the growth and energetic reserves in muscle, hepatopancreas and hemolymph of growing juvenile crayfish. Exposure to two different glyphosate and POEA mixtures caused lower somatic growth and decreased muscle protein levels. These effects, caused by both compounds interacting in the mixture, could also be synergistic because they were expressed even at the lowest concentration. The decrease in protein levels could be related to the greater use of other energy reserves. This hypothesis is supported by the decrease in muscle glycogen stores due to glyphosate exposure and the decrease in lipid reserves associated with exposure to POEA.
