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Interaction of genotype with production system for reproductive performance in rainbow trout
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Abstracts / Aquaculture 272S1 (2007) S238–S321
mass on chromosome IV and indicated dominance (mean d/a = 0.97).
Introgressive hybridization and comparative growth performance of two Nile tilapia (Chitralada and Red-Stirling) and their crosses
doi:10.1016/j.aquaculture.2007.07.085
A.W.S. Hilsdorf, A.A. Moreira, J. Rodrigues De Freitas Rua Dr. Cândido Xavier de Almeida Souza, 200, Mogi das Cruzes, Brazil, CEP 08780-911 FISH mapping of 5S rRNA genes in chromosomes of North American abalone species, Haliotis rufescens and H. fulgens N.K. Hernández-Ibarra a, A.M. Ibarra a, P. Cruz a, A.R. Leitch b a Centro de Investigaciones Biológicas del Noroeste S.C., Aquaculture Genetics Lab. Mar Bermejo 195, Playa Palo Santa Rita 23090, La Paz, B.C.S., Mexico b School of Biological Sciences, Queen Mary University of London Mile End Road, London E1 4NS, UK The abalone species H. rufescens and H. fulgens are important in North American aquaculture. Consequently there is a need to generate physical and chromosome genetic maps of these species to facilitate breeding programs. At CIBNOR in Mexico, mapping of different DNA sequences including ribosomal DNA (rDNA) is under investigation in the diploid species, hybrids, and allotriploids. We have mapped the 5S ribosomal RNA (rRNA) gene cluster to both abalone species. The 5S rRNA genic sequences have a conserved length of 120 bp and are separated by a non-transcribed spacer (NTS) of variable length. The data indicate several 5S rDNA families within abalone species. PCR amplification of 5S rRNA genes was performed using primers designed against Mytilus edulis 5S rDNA and the product was labeled with biotin and used as a probe for FISH. Detection of probe hybridization sites with streptavidin-CY3 gave good fluorescence signal. The location of 5S rDNA sequences is conserved in the two species and occurs at interstitial regions on the long arm of a pair of metacentric chromosomes that are the second largest pair in the karyotypes. The similar morphologies and map positions of 5S rDNA in the two species prevent identification of the parental origin of the homologous chromosomes in hybrids and allotriploids. However the site provides a valuable genetic marker on the 5S rDNA-carrying chromosome. doi:10.1016/j.aquaculture.2007.07.086
Among the different fish species cultivated in Brazil, Nile tilapia (Oreochromis niloticus) has shown an increasing economical importance in the last decade. The Brazilian market for tilapia has been following the same trend with increased consumption of red tilapia, mainly in restaurants and supermarkets. Growth performance of two O. niloticus strains, Chitralada and Red-Stirling, their reciprocal crossbred and the Israeli tetra-hybrid ND-56 were assessed in net cages under onfarming conditions. Throughout 268 days of grow-out, the strains were weighed monthly and mortality, feed consumption and water quality were recorded. Ten rigid net cages (1.5× 1.5 × 1.7 m) immersed in a 10 ha reservoir were linearly arranged near the reservoir outlet following a completely randomized design with two replicates for each treatment (strain). Each cage was stocked with 459 fish (120 fish m-3). The final mean weights were higher for Chitralada (557.20 g) and the reciprocal crossbreds (522.95, 496.40 g) than those of Red-Stirling (421.90 g). All treatments outperformed the ND-56 tetra hybrid. The overall growth rate showed that crossbred performed as well as the parental lines. All crossbred progeny presented red colouration with variable pattern of black marks. In order to decrease the amount of black marks introgressive breeding was carried out. Progeny of the F1 backcross were then assessed for pattern of colouration and growth performance. doi:10.1016/j.aquaculture.2007.07.087
Interaction of genotype with production system for reproductive performance in rainbow trout G. Hörstgen-Schwark a, P. Pornsoping b, G. Unsrisong b, T. Vearasilp c a Institute of Animal Husbandry and Genetics, GeorgAugust-University Göttingen, Albrecht-Thaer-Weg 3, D 37075 Göttingen, Germany b Chiang Mai Inland Fisheries Research and Development Center, Department of Fisheries, ChiangMai, 50290, Thailand c Chiang Mai University, Faculty of Agriculture, Department of Animal Science, ChiangMai, Thailand
Abstracts / Aquaculture 272S1 (2007) S238–S321
A population comparison of European rainbow trout was conducted to study the effect of photoperiod and water temperature on reproductive performance. In March, 15-month-old rainbow trout of each population were divided randomly into three groups. The first group (n = 105) was exposed to an increasing photoperiod until June (16 h light) whereafter illumination length was decreased until December (8 h). Water temperature was kept at 16 °C from March until December. Group 2 fish (n = 105) were kept under the same light regime as group 1 fish while water temperature varied from 18 °C (March) to 20 °C (June) and to 16 °C (December). Fish of group 3 (n = 420) were subjected to group 2 water temperatures whereas daylight exposure was restricted to 12 h (March), 13 h (June) and 11 h (December) respectively. The spawning season of the 23-month-old broodstock lasted from November to January. Eggs from nearly all females in group 1 could be obtained before January, whereas the percentage of females with ovulated eggs was reduced to 84% in group 2 and to 68% in group 3. The fertilization and survival rates of eggs were highest in group 1 and lowest in group 2. For average hatching rates, no significant differences could be found between treatment groups. Within treatment groups, significant differences between populations were observed for nearly all traits studied. The best mean hatching rates observed in group 1 (60%) and 3 (45%) were obtained from the same population. This population was chosen as breeding base to further improve reproductive performance.
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fry in freshwater hatcheries, and to smolts in the 12 week period following transfer to sea water. There is a substantial genetic component to IPN resistance within commercial lines. To investigate whether this genetic component includes loci of major effect, a genome-wide QTL scan was performed within commercially bred families that had received a natural postseawater transfer IPN challenge. Eleven large full-sib families were chosen for analysis with intermediate levels of IPN mortality, to maximise the chances of within-family segregation for putative resistance QTL. To utilise the large difference between male and female recombination rate, a two-stage genotyping and analysis strategy was employed. Initially, the parents and offspring were genotyped for between two and four markers per linkage group, and a sire-based QTL analysis was used to detect linkage groups with significant effects on IPN resistance. To confirm the QTL and to provide an improved estimate of position, a dam-based analysis was then employed. One major QTL was located at the genome-wide significance level, with two further QTL that reached the suggestive level of significance. Offspring inheriting the favourable allele from the segregating sires at the largest QTL have an average mortality of 0.26, compared to 0.67 for the unfavourable allele, thus demonstrating the potential for its use in marker-assisted selection programmes to improve the resistance of commercial salmon to IPN and reduce disease-related mortality. doi:10.1016/j.aquaculture.2007.07.089
doi:10.1016/j.aquaculture.2007.07.088
Mapping QTL affecting resistance to infectious pancreatic necrosis (IPN) in Atlantic salmon (Salmo salar) R.D. Houston a , D.R. Guy b, A. Hamilton b, J. Ralph b, N. Spreckley b, J.B. Taggart c, B.J. McAndrew c, C.S. Haley a, S.C. Bishop a a Division of Genetics and Genomics, Roslin Institute, Roslin, Midlothian EH25 9PS, UK b Landcatch Natural Selection, Cooperage Way, Alloa, Clackmannanshire FK10 3LP, UK c Institute of Aquaculture, University of Stirling, Stirling FK9 4LA, UK Infectious pancreatic necrosis (IPN) is a viral disease that presents a major challenge to the salmon farming industry. IPN can cause significant mortality to salmon
Characterization of differentially expressed genes between resident and anadromous forms of brown trout (Salmo trutta L.) in intestine tissue O. Le Provost a, S. Hubert a,c, A.M. O'Keeffe a , D. Cotter b, M.T. Cairns a a National Diagnostics Centre, NUI, Galway, Ireland b Marine Institute, Furnace, Newport, Ireland c Department of Zoology, NUI, Galway, Ireland In Ireland, sea trout populations have collapsed since the early 1980s. A detailed knowledge of trout behavioural strategies and the factors that influence these are important for effective fishery management. Some individuals from the same population will remain in fresh water all their lives and these fishes are called brown trout. Others will spend their first 2 years or so in fresh water before turning into silvery smolts and migrating to sea (estuarine and coastal waters), these are
Abstracts / Aquaculture 272S1 (2007) S238–S321
mass on chromosome IV and indicated dominance (mean d/a = 0.97).
Introgressive hybridization and comparative growth performance of two Nile tilapia (Chitralada and Red-Stirling) and their crosses
doi:10.1016/j.aquaculture.2007.07.085
A.W.S. Hilsdorf, A.A. Moreira, J. Rodrigues De Freitas Rua Dr. Cândido Xavier de Almeida Souza, 200, Mogi das Cruzes, Brazil, CEP 08780-911 FISH mapping of 5S rRNA genes in chromosomes of North American abalone species, Haliotis rufescens and H. fulgens N.K. Hernández-Ibarra a, A.M. Ibarra a, P. Cruz a, A.R. Leitch b a Centro de Investigaciones Biológicas del Noroeste S.C., Aquaculture Genetics Lab. Mar Bermejo 195, Playa Palo Santa Rita 23090, La Paz, B.C.S., Mexico b School of Biological Sciences, Queen Mary University of London Mile End Road, London E1 4NS, UK The abalone species H. rufescens and H. fulgens are important in North American aquaculture. Consequently there is a need to generate physical and chromosome genetic maps of these species to facilitate breeding programs. At CIBNOR in Mexico, mapping of different DNA sequences including ribosomal DNA (rDNA) is under investigation in the diploid species, hybrids, and allotriploids. We have mapped the 5S ribosomal RNA (rRNA) gene cluster to both abalone species. The 5S rRNA genic sequences have a conserved length of 120 bp and are separated by a non-transcribed spacer (NTS) of variable length. The data indicate several 5S rDNA families within abalone species. PCR amplification of 5S rRNA genes was performed using primers designed against Mytilus edulis 5S rDNA and the product was labeled with biotin and used as a probe for FISH. Detection of probe hybridization sites with streptavidin-CY3 gave good fluorescence signal. The location of 5S rDNA sequences is conserved in the two species and occurs at interstitial regions on the long arm of a pair of metacentric chromosomes that are the second largest pair in the karyotypes. The similar morphologies and map positions of 5S rDNA in the two species prevent identification of the parental origin of the homologous chromosomes in hybrids and allotriploids. However the site provides a valuable genetic marker on the 5S rDNA-carrying chromosome. doi:10.1016/j.aquaculture.2007.07.086
Among the different fish species cultivated in Brazil, Nile tilapia (Oreochromis niloticus) has shown an increasing economical importance in the last decade. The Brazilian market for tilapia has been following the same trend with increased consumption of red tilapia, mainly in restaurants and supermarkets. Growth performance of two O. niloticus strains, Chitralada and Red-Stirling, their reciprocal crossbred and the Israeli tetra-hybrid ND-56 were assessed in net cages under onfarming conditions. Throughout 268 days of grow-out, the strains were weighed monthly and mortality, feed consumption and water quality were recorded. Ten rigid net cages (1.5× 1.5 × 1.7 m) immersed in a 10 ha reservoir were linearly arranged near the reservoir outlet following a completely randomized design with two replicates for each treatment (strain). Each cage was stocked with 459 fish (120 fish m-3). The final mean weights were higher for Chitralada (557.20 g) and the reciprocal crossbreds (522.95, 496.40 g) than those of Red-Stirling (421.90 g). All treatments outperformed the ND-56 tetra hybrid. The overall growth rate showed that crossbred performed as well as the parental lines. All crossbred progeny presented red colouration with variable pattern of black marks. In order to decrease the amount of black marks introgressive breeding was carried out. Progeny of the F1 backcross were then assessed for pattern of colouration and growth performance. doi:10.1016/j.aquaculture.2007.07.087
Interaction of genotype with production system for reproductive performance in rainbow trout G. Hörstgen-Schwark a, P. Pornsoping b, G. Unsrisong b, T. Vearasilp c a Institute of Animal Husbandry and Genetics, GeorgAugust-University Göttingen, Albrecht-Thaer-Weg 3, D 37075 Göttingen, Germany b Chiang Mai Inland Fisheries Research and Development Center, Department of Fisheries, ChiangMai, 50290, Thailand c Chiang Mai University, Faculty of Agriculture, Department of Animal Science, ChiangMai, Thailand
Abstracts / Aquaculture 272S1 (2007) S238–S321
A population comparison of European rainbow trout was conducted to study the effect of photoperiod and water temperature on reproductive performance. In March, 15-month-old rainbow trout of each population were divided randomly into three groups. The first group (n = 105) was exposed to an increasing photoperiod until June (16 h light) whereafter illumination length was decreased until December (8 h). Water temperature was kept at 16 °C from March until December. Group 2 fish (n = 105) were kept under the same light regime as group 1 fish while water temperature varied from 18 °C (March) to 20 °C (June) and to 16 °C (December). Fish of group 3 (n = 420) were subjected to group 2 water temperatures whereas daylight exposure was restricted to 12 h (March), 13 h (June) and 11 h (December) respectively. The spawning season of the 23-month-old broodstock lasted from November to January. Eggs from nearly all females in group 1 could be obtained before January, whereas the percentage of females with ovulated eggs was reduced to 84% in group 2 and to 68% in group 3. The fertilization and survival rates of eggs were highest in group 1 and lowest in group 2. For average hatching rates, no significant differences could be found between treatment groups. Within treatment groups, significant differences between populations were observed for nearly all traits studied. The best mean hatching rates observed in group 1 (60%) and 3 (45%) were obtained from the same population. This population was chosen as breeding base to further improve reproductive performance.
S269
fry in freshwater hatcheries, and to smolts in the 12 week period following transfer to sea water. There is a substantial genetic component to IPN resistance within commercial lines. To investigate whether this genetic component includes loci of major effect, a genome-wide QTL scan was performed within commercially bred families that had received a natural postseawater transfer IPN challenge. Eleven large full-sib families were chosen for analysis with intermediate levels of IPN mortality, to maximise the chances of within-family segregation for putative resistance QTL. To utilise the large difference between male and female recombination rate, a two-stage genotyping and analysis strategy was employed. Initially, the parents and offspring were genotyped for between two and four markers per linkage group, and a sire-based QTL analysis was used to detect linkage groups with significant effects on IPN resistance. To confirm the QTL and to provide an improved estimate of position, a dam-based analysis was then employed. One major QTL was located at the genome-wide significance level, with two further QTL that reached the suggestive level of significance. Offspring inheriting the favourable allele from the segregating sires at the largest QTL have an average mortality of 0.26, compared to 0.67 for the unfavourable allele, thus demonstrating the potential for its use in marker-assisted selection programmes to improve the resistance of commercial salmon to IPN and reduce disease-related mortality. doi:10.1016/j.aquaculture.2007.07.089
doi:10.1016/j.aquaculture.2007.07.088
Mapping QTL affecting resistance to infectious pancreatic necrosis (IPN) in Atlantic salmon (Salmo salar) R.D. Houston a , D.R. Guy b, A. Hamilton b, J. Ralph b, N. Spreckley b, J.B. Taggart c, B.J. McAndrew c, C.S. Haley a, S.C. Bishop a a Division of Genetics and Genomics, Roslin Institute, Roslin, Midlothian EH25 9PS, UK b Landcatch Natural Selection, Cooperage Way, Alloa, Clackmannanshire FK10 3LP, UK c Institute of Aquaculture, University of Stirling, Stirling FK9 4LA, UK Infectious pancreatic necrosis (IPN) is a viral disease that presents a major challenge to the salmon farming industry. IPN can cause significant mortality to salmon
Characterization of differentially expressed genes between resident and anadromous forms of brown trout (Salmo trutta L.) in intestine tissue O. Le Provost a, S. Hubert a,c, A.M. O'Keeffe a , D. Cotter b, M.T. Cairns a a National Diagnostics Centre, NUI, Galway, Ireland b Marine Institute, Furnace, Newport, Ireland c Department of Zoology, NUI, Galway, Ireland In Ireland, sea trout populations have collapsed since the early 1980s. A detailed knowledge of trout behavioural strategies and the factors that influence these are important for effective fishery management. Some individuals from the same population will remain in fresh water all their lives and these fishes are called brown trout. Others will spend their first 2 years or so in fresh water before turning into silvery smolts and migrating to sea (estuarine and coastal waters), these are