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Selection of hybrids between crucian carp (Carassius auratus Gibelio Bloch.) and common carp (Cyprinus carpio L.) for improvement of reproductive ability: successes and problems
T. Sanchez et al. /Aquaculture
214
137 (1995) 271-284
of the increment did not change when the fish were fed either with dry standard food or with live food. This was true in the selected lines, in both crosses and in the base population. On the contrary, the mean value of length at 1 month increased when the fish were fed with the live diet and this occurred in the base population, the L line and both crosses but not in the H line. The absence of increase in the H line might be explained as a reduction of sensitivity due to the antagonistic applied selection. In conclusion, the selection applied for increased length at 2 months produced an increase in body size and growth rate. The different sensitivity showed by the length at 1 month and by the length increment from 1 to 2 months in the lines and crosses, and the different behaviour of these two traits observed when the crosses were compared to the parental lines, seems to support the possibility of a separate genetic control for size and growth rate in the population Poecilia reticuluta.
Selection of hybrids between crucian carp (Carassius auratus Gibelio Bloch.) and common carp (Cyprinus carpio L.) for improvement of reproductive ability: successes and problems A.V. Recoubratsky
a, O.V. Emelyanova E.V. Pankratieva a
a, N.B. Cherfas b,
aAll-Russian Research Institute of Pond Fisheries, Moscow Area 141821, Russia ’ Agriculture Research Organization, Fish and Agriculture Research station, Dor, Israel
Abstract The males of hybrids between bisexual crucian carp and common carp has been shown to be sterile with some females producing unreduced diploid eggs. Induced gynogenesis was used to reproduce these hybrids for four gynogenetic generations (Gl-G4). Backcrossing the hybrid females with the parent species males results in sterile triploid progenies. Owing to valuable fish culture traits inherited from the parent species (fast growth rate of common carp and high resistance to hypoxia and against diseases of crucian carp) as well as sterility, triploid hybrids are of great interest for fish culture. As reproductive ability of Fl females was very low, mass selection was performed to increase the yield of backcross triploid hybrids. The results of selection being performed through four subsequent generations of diploid hybrids (FJl - G3) are presented in this work. Some reproductive traits have been improved as a result of selection. The number of fish without cytological and morphological abnormalities of gonadal structure has significantly increased (from 11.8% in F’l to 96.3% in G3). The frequency of females giving eggs after pituitary injection has risen from 26 to 91% and female fecundity has risen from 39 to 117 g per kg body weight, respectively. The selection success has allowed us to obtain tens of millions of triploid hybrid larvae for industrial rearing. At the same time we have faced a specific problem. The eggs produced by hybrid females consist of both exact diploid ( 100 chromosomes) and aneuploid (38-90 chromosomes) gametes. The survival of gynogenetic and backcrsoss embryos depends on the proportion of diploid gametes which varies
T. Sanchez et al. /Aquaculture
137 (1995) 271-284
275
considerably from female to female. The average output of gynogenetic and backcross larvae has not increased through gynogenetic generations accounting for 4555% in Gl-G3. Investigations of individual ability of G3 hybrid females to produce gynogenetic and backcross progenies carrying out within two spawning seasons (1992 and 1993) have revealed that repetitiveness of these indices expressed in terms of correlation coefficients is insignificant ranging from 0.2 to 0.4. This fact indicates that paratypic variation of the proportion of competent diploid gametes is essential and selection of hybrid females for increased survival of backcross embryos is a rather complicated problem.
Selection for enhanced disease resistance in Atlantic salmon Kjersti T. Fjalestad, Trygve Gjedrem, Terje Refstie AKVAFORSK
(Institute of Aquaculture Research Itd). N-6600 Sunndalsora, Norway
Abstract A selection program for Atlantic salmon has been aimed at establishing lines with respectively high and low response to different immune parameters, and lines based on high and low survival rate after challenging families with furunculosis. Several parameters have been analysed within the 20 most resistant families and the ten most susceptible families after challenging 50 Atlantic salmon families with furunculosis. Lysozyme, serum haemolytic activity, total immunoglobulin levels (total IgM) , and the levels of other plasma proteins have been assessed together with levels of specific antibodies against Vibrio anguillarum antigen (causing vibriosis), V. salmonicida O-antigen (causing coldwater vibriosis) and Aeromomzssalmonicida (causing funmculosis), following injection of vaccines against these pathogens. Lysozyme, total IgM, cu,-antiplasmin and antibody titre against A. salmonicidu, were chosen as selection criteria in a selection experiment together with selection for survival after challenge with furunculosis. In addition to high and low lines for each of the traits two control groups of unselected fish were made. Fish from the selection lines and control groups were challenged with furunculosis, cold water vibriosis and infectious salmon anemia (ISA). Homogenity of survival distribution functions was tested using the Wilcoxon and log rank test. Significant differences in mortality between the high and low selection lines for survival against furunculosis, antibody titre againstA. salmonicida and total IgM, were observed,when challenging with furunculosis and coldwater vibriosis. There were no differences between the high and low lysozyme lines. Significant differences in mortality between the high and low cu,-antiplasmin selection line, when challenging with coldwater vibriosis, were also observed. There were no significant differences in mortality between the selection lines when challenged with infectious salmon anemia (ISA).
214
137 (1995) 271-284
of the increment did not change when the fish were fed either with dry standard food or with live food. This was true in the selected lines, in both crosses and in the base population. On the contrary, the mean value of length at 1 month increased when the fish were fed with the live diet and this occurred in the base population, the L line and both crosses but not in the H line. The absence of increase in the H line might be explained as a reduction of sensitivity due to the antagonistic applied selection. In conclusion, the selection applied for increased length at 2 months produced an increase in body size and growth rate. The different sensitivity showed by the length at 1 month and by the length increment from 1 to 2 months in the lines and crosses, and the different behaviour of these two traits observed when the crosses were compared to the parental lines, seems to support the possibility of a separate genetic control for size and growth rate in the population Poecilia reticuluta.
Selection of hybrids between crucian carp (Carassius auratus Gibelio Bloch.) and common carp (Cyprinus carpio L.) for improvement of reproductive ability: successes and problems A.V. Recoubratsky
a, O.V. Emelyanova E.V. Pankratieva a
a, N.B. Cherfas b,
aAll-Russian Research Institute of Pond Fisheries, Moscow Area 141821, Russia ’ Agriculture Research Organization, Fish and Agriculture Research station, Dor, Israel
Abstract The males of hybrids between bisexual crucian carp and common carp has been shown to be sterile with some females producing unreduced diploid eggs. Induced gynogenesis was used to reproduce these hybrids for four gynogenetic generations (Gl-G4). Backcrossing the hybrid females with the parent species males results in sterile triploid progenies. Owing to valuable fish culture traits inherited from the parent species (fast growth rate of common carp and high resistance to hypoxia and against diseases of crucian carp) as well as sterility, triploid hybrids are of great interest for fish culture. As reproductive ability of Fl females was very low, mass selection was performed to increase the yield of backcross triploid hybrids. The results of selection being performed through four subsequent generations of diploid hybrids (FJl - G3) are presented in this work. Some reproductive traits have been improved as a result of selection. The number of fish without cytological and morphological abnormalities of gonadal structure has significantly increased (from 11.8% in F’l to 96.3% in G3). The frequency of females giving eggs after pituitary injection has risen from 26 to 91% and female fecundity has risen from 39 to 117 g per kg body weight, respectively. The selection success has allowed us to obtain tens of millions of triploid hybrid larvae for industrial rearing. At the same time we have faced a specific problem. The eggs produced by hybrid females consist of both exact diploid ( 100 chromosomes) and aneuploid (38-90 chromosomes) gametes. The survival of gynogenetic and backcrsoss embryos depends on the proportion of diploid gametes which varies
T. Sanchez et al. /Aquaculture
137 (1995) 271-284
275
considerably from female to female. The average output of gynogenetic and backcross larvae has not increased through gynogenetic generations accounting for 4555% in Gl-G3. Investigations of individual ability of G3 hybrid females to produce gynogenetic and backcross progenies carrying out within two spawning seasons (1992 and 1993) have revealed that repetitiveness of these indices expressed in terms of correlation coefficients is insignificant ranging from 0.2 to 0.4. This fact indicates that paratypic variation of the proportion of competent diploid gametes is essential and selection of hybrid females for increased survival of backcross embryos is a rather complicated problem.
Selection for enhanced disease resistance in Atlantic salmon Kjersti T. Fjalestad, Trygve Gjedrem, Terje Refstie AKVAFORSK
(Institute of Aquaculture Research Itd). N-6600 Sunndalsora, Norway
Abstract A selection program for Atlantic salmon has been aimed at establishing lines with respectively high and low response to different immune parameters, and lines based on high and low survival rate after challenging families with furunculosis. Several parameters have been analysed within the 20 most resistant families and the ten most susceptible families after challenging 50 Atlantic salmon families with furunculosis. Lysozyme, serum haemolytic activity, total immunoglobulin levels (total IgM) , and the levels of other plasma proteins have been assessed together with levels of specific antibodies against Vibrio anguillarum antigen (causing vibriosis), V. salmonicida O-antigen (causing coldwater vibriosis) and Aeromomzssalmonicida (causing funmculosis), following injection of vaccines against these pathogens. Lysozyme, total IgM, cu,-antiplasmin and antibody titre against A. salmonicidu, were chosen as selection criteria in a selection experiment together with selection for survival after challenge with furunculosis. In addition to high and low lines for each of the traits two control groups of unselected fish were made. Fish from the selection lines and control groups were challenged with furunculosis, cold water vibriosis and infectious salmon anemia (ISA). Homogenity of survival distribution functions was tested using the Wilcoxon and log rank test. Significant differences in mortality between the high and low selection lines for survival against furunculosis, antibody titre againstA. salmonicida and total IgM, were observed,when challenging with furunculosis and coldwater vibriosis. There were no differences between the high and low lysozyme lines. Significant differences in mortality between the high and low cu,-antiplasmin selection line, when challenging with coldwater vibriosis, were also observed. There were no significant differences in mortality between the selection lines when challenged with infectious salmon anemia (ISA).