Study the usage of rotifer (Brachionus plicatilis ) Qualitative and Quantitative Study of Sturgeon finger lings fram the time of production up to their releas
The present study that was conducted in collaboration with the departments of fish breeding and rearing, pathology and stock assessment of the International Sturgeon Research Institute at the Shahid Beheshti hatchery commenced on 26 February 2002 and ended on 7 June 2002 simultaneously with the breeding of beluga breeders. About 230 sturgeon specimens were studied of which 176 belonged to A. persicus spawners (103 females used for artificial breeding, 16 females not used for artificial breeding and 57 males), 46 A. stellatus spawners (13 females used for artificial breeding, 20 females not used for artificial breeding and 13 males), 3 A. nudiventris spawners and five H. huso female spawners. The total length of A. persicus spawners used for artificial breeding ranged from 131.5 to 211 cm with an average length of 172.5 cm and their weight ranged from 14 to 49 Kg. The minimum and maximum weight of eggs was 9 and 1.5 Kg, respectively and the minimum and maximum number of eggs per gram was 46 and 67 eggs, respectively. The maximum condition factor for spawners was 0.94 and the minimum condition factor was 0.49 (average 0.74). The age of spawners ranged from 12 to 20 years and the minimum and maximum time taken by spawners to respond to breeding was 293.8 and 486 t?. The GV1 in these breeders ranged from 6.2 to 17.5 and GV2 ranged from 5.3 to 9.3. The maximum fertilization rate was 100 %. The total length of A. persicus breeders that were not used in artificial breeding ranged from 152 to 203 cm and their weight ranged from 14 to 46 Kg. The minimum and maximum weight of eggs was 3.2 and 8.5 Kg, respectively and the minimum and maximum number of eggs per gram was 46 and 64 eggs, respectively. The maximum condition factor for spawners was 0.81 and the minimum condition factor was 0.39 (average 0.69). The age of spawners ranged from 16 to 19 years. The GV1 in these breeders ranged from 7.8 to 16.3 and GV2 ranged from 6.5 to 8.2. Total length of male A. persicus breeders ranged from 129 to 178 cm and their weight ranged from 7 to 25.5 Kg. The maximum age of these breeders was 17 years and their minimum age was 11 years. The condition factor in these breeders ranged from 0.33 to 0.84. In A. stellatus breeders total length ranged from 128.5 to 163 cm and weight ranged from 7 to 14.5 Kg. The minimum and maximum weight of eggs was 1 and 2.7 Kg, respectively and the minimum and maximum number of eggs per gram was 67 and 129 eggs, respectively. The maximum condition factor for spawners was 0.58 and the minimum condition factor was 0.37 (average 0.48). The age of spawners ranged from 10 to 16 years and the minimum and maximum time taken by spawners to respond to breeding was 276.8 and 737.3 t?. The GV1 in these breeders ranged from 9.1 to16.2 and GV2 ranged from 3.64 to11. The maximum fertilization rate was 90 %. The total length of A. stellatus breeders that were not used in artificial breeding ranged from 129.5 to 165.5 cm and their weight ranged from 7.3 to 17 Kg. The minimum and maximum weight of eggs was 1.2 and 3 Kg, respectively and the minimum and maximum number of eggs per gram was 71 and 124 eggs, respectively. The maximum condition factor for spawners was 0.76 and the minimum condition factor was 0.39 (average 0.51). The age of spawners ranged from 8 to 14 years. Statistical analysis of data recorded other than GV showed no significant differences between the parameters measured in A. persicus breeders used for artificial breeding and those not used in artificial breeding. Considering the importance of the pathological state of spawners used for breeding the frequency and cause for mortality in incubators as well as vniro tanks and so also the condition of sturgeon fry in earthen ponds in terms of bacterial and parasitical infection and the effects of these infections on survival rate and growth of fry and the quality control of spawners and fry were carried out in the Shahid Beheshti and Yousefpour hatcheries. The 149 sturgeon breeders studied (109 A. persicus, 36 A. stellatus, 3 A. nudiventris and 1 H. huso) at the Shahid Beheshti hatchery showed 8 kinds of parasitical worms. The results obtained from this study indicate that A. stellatus breeders showed the maximum number of digestive tract parasitical worms. Cucullanus spherorocephalus with a prevalence rate of 84.26 % showed the highest abundance and Corynosoma strumosum and Eubothrium asipenserinum with a prevalence rate of 0.93 % showed the minimum abundance in A. persicus spawners. On the basis of this study the digestive tract parasite Skrjabinopsolus semiarmatus with a prevalence rate of 77.78 % showed the maximum abundance and Amphilina foliacea and Eustrongylides excisus with a prevalence rate of 2.78 % showed the minimum abundance in A. stellatus spawners. The relationship between weight of spawners and weight of eggs harvested was studied with prevalence of digestive tract parasites. No parasitical and bacterial infection was observed in the 100 sturgeon larvae examined. Examination of sturgeon fingerings in the two hatcheries in the middle and again at the end of the rearing period showed no signs of bacterial and fungal infections. In the parasitical examination of sturgeon fingerlings studied Triclodina and Diplostomum were identified. Percentage incidences of Diplostomum in the Shahid Beheshti hatchery was 4.97 % and that in the Dr. Yousefpour hatchery was 10.09 %. The percentage incidences of Triclodina in the Shahid Beheshti and Yousefpour hatcheries were 46.68 % and 70.76 %, respectively. However no Diplostomum infections were observed in the 113 A. stellatus specimens examined in the Shahid Beheshti hatchery. Results obtained from this study indicate that A. stellatus specimens from the Dr. Yousefpour hatchery showed higher prevalence to Triclodina as well as Diplostomum infection as compared to the A. stellatus studied in the Shahid Beheshti hatchery. Monitoring the hygienic conditions in the two hatcheris under study during mid-rearing period and at the end of the rearing period revealed an increase in prevalence rate and intensity of Triclodina and Diplostomum infection at the end of the rearing period. Examination of pectoral fin of sturgeon fingerlings indicated higher incidences of pectoral fin deformities in fingerlings studied in the Shahid Beheshti hatchery than in the Dr. Yousefpour hatchery. In 2002 release of fingerlings started on 15.06.2002 at the Shahid Beheshti hatchery and on 8.9.2002 at the Dr. Yousefpour hatchery. Totally 4809554 fingerlings were released into the Sepidrud River. Totally 2889462 fingerlings were released from 31 earthen ponds (2 hectares) at the Shahid Beheshti hatchery starting from 17.6 2002 to 21.7.2002 out of which 2563159 fingerlings belonged to A. persicus that comprised 88.7 % of the total abundance with a mean weight of 5 g and mean length of 10.9 cm, 324789 fingerlings belonged to A. stellatus that comprised 11.2 % of the total abundance with a mean weight of 6.9 g and mean length of 16.2 cm, 1514 fingerlings belonged to A. nudiventris comprising 0.1 % of the total abundance with a mean weight of 12.9 g and a mean length of 14.5 cm. Out of the total number of fingerlings released 74.5 % of A. persicus, 98 % of A. stellatus and 100 % of A. nudiventris were above 3 g per fish in weight. The survival rate of reared fishes was 45.47 % for A. persicus 0.89 % for A. nudiventris. As the exact number of A. stellatus larvae introduced to the rearing ponds was not known the survival rate for this species was not estimated. In A. persicus specific growth rate (3.36) was very low while condition factor (0.41) was moderate. In A. nudiventris growth rate (3.37) and condition factor (0.41) were moderate. About 1920092 fingerlings were released from the Dr. Yousefpour hatchery starting from 15.06.2003 to 08.09.2003 of which 1895948 fingerlings belonged to A. persicus that comprised 98.8 % of the total number with a mean weight of 3.4 g and a mean length of 9.4 cm, 24144 fingerlings belonged to A. stellatus comprising 1.3 % of the total number with a mean weight of 7.5 g and a mean length of 11.7 cm Out of the total number of fingerlings released 43.7 % of A. persicus and 31.7 % of A. stellatus fingerlings were above 3 g per fish in weight. The survival rates of the reared fishes were 24.2 % for A. persicus and 14.6 % for A. stellatus. In A. persicus the growth rate (2.99) was low while condition factor (0.38) was moderate. In A. stellatus the growth rate (3.06) and condition factor (0.30) were low. Significant differences (P<0.05) were observed on comparing condition factor (F=4.573), survival rates (F=20.971) and rearing period (F=5.038) in A. persicus in the two hatcheries. Therefore A. persicus fingerlings released from the Shahid Beheshti hatchery showed better survival rates and attained the maximum mean weights in a shorter rearing period, whereas fingerlings released from Dr. Yousefpour hatchery were in a better state regarding condition factor.
| Main Authors: | , , , , , , , , , , , |
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| Format: | Report biblioteca |
| Language: | Persian |
| Published: |
Iranian Fisheries Science Research Institute
2005
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| Subjects: | Brachionus plicatilis, Quantitative, Sturgeon, Fingerlings, Qualitative, |
| Online Access: | http://hdl.handle.net/1834/14444 |
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| Summary: | The present study that was conducted in collaboration with the departments of fish breeding and
rearing, pathology and stock assessment of the International Sturgeon Research Institute at the
Shahid Beheshti hatchery commenced on 26 February 2002 and ended on 7 June 2002
simultaneously with the breeding of beluga breeders.
About 230 sturgeon specimens were studied of which 176 belonged to A. persicus spawners (103
females used for artificial breeding, 16 females not used for artificial breeding and 57 males), 46 A. stellatus spawners (13 females used for artificial breeding, 20 females not used for artificial breeding
and 13 males), 3 A. nudiventris spawners and five H. huso female spawners. The total length of A. persicus spawners used for artificial breeding ranged from 131.5 to 211 cm
with an average length of 172.5 cm and their weight ranged from 14 to 49 Kg. The minimum and
maximum weight of eggs was 9 and 1.5 Kg, respectively and the minimum and maximum number of
eggs per gram was 46 and 67 eggs, respectively. The maximum condition factor for spawners was
0.94 and the minimum condition factor was 0.49 (average 0.74). The age of spawners ranged from 12
to 20 years and the minimum and maximum time taken by spawners to respond to breeding was
293.8 and 486 t?. The GV1 in these breeders ranged from 6.2 to 17.5 and GV2 ranged from 5.3 to 9.3. The maximum fertilization rate was 100 %.
The total length of A. persicus breeders that were not used in artificial breeding ranged from 152 to
203 cm and their weight ranged from 14 to 46 Kg. The minimum and maximum weight of eggs was 3.2
and 8.5 Kg, respectively and the minimum and maximum number of eggs per gram was 46 and 64
eggs, respectively. The maximum condition factor for spawners was 0.81 and the minimum condition
factor was 0.39 (average 0.69). The age of spawners ranged from 16 to 19 years. The GV1 in these
breeders ranged from 7.8 to 16.3 and GV2 ranged from 6.5 to 8.2. Total length of male A. persicus breeders ranged from 129 to 178 cm and their weight ranged from
7 to 25.5 Kg. The maximum age of these breeders was 17 years and their minimum age was 11
years. The condition factor in these breeders ranged from 0.33 to 0.84.
In A. stellatus breeders total length ranged from 128.5 to 163 cm and weight ranged from 7 to 14.5
Kg. The minimum and maximum weight of eggs was 1 and 2.7 Kg, respectively and the minimum and
maximum number of eggs per gram was 67 and 129 eggs, respectively. The maximum condition
factor for spawners was 0.58 and the minimum condition factor was 0.37 (average 0.48). The age of
spawners ranged from 10 to 16 years and the minimum and maximum time taken by spawners to
respond to breeding was 276.8 and 737.3 t?. The GV1 in these breeders ranged from 9.1 to16.2 and
GV2 ranged from 3.64 to11. The maximum fertilization rate was 90 %.
The total length of A. stellatus breeders that were not used in artificial breeding ranged from 129.5
to 165.5 cm and their weight ranged from 7.3 to 17 Kg. The minimum and maximum weight of eggs
was 1.2 and 3 Kg, respectively and the minimum and maximum number of eggs per gram was 71 and
124 eggs, respectively. The maximum condition factor for spawners was 0.76 and the minimum
condition factor was 0.39 (average 0.51). The age of spawners ranged from 8 to 14 years. Statistical analysis of data recorded other than GV showed no significant differences between the
parameters measured in A. persicus breeders used for artificial breeding and those not used in
artificial breeding. Considering the importance of the pathological state of spawners used for breeding the frequency
and cause for mortality in incubators as well as vniro tanks and so also the condition of sturgeon fry in
earthen ponds in terms of bacterial and parasitical infection and the effects of these infections on
survival rate and growth of fry and the quality control of spawners and fry were carried out in the
Shahid Beheshti and Yousefpour hatcheries. The 149 sturgeon breeders studied (109 A. persicus, 36 A. stellatus, 3 A. nudiventris and 1 H. huso) at the Shahid Beheshti hatchery showed 8 kinds of parasitical worms. The results obtained from
this study indicate that A. stellatus breeders showed the maximum number of digestive tract parasitical
worms. Cucullanus spherorocephalus with a prevalence rate of 84.26 % showed the highest
abundance and Corynosoma strumosum and Eubothrium asipenserinum with a prevalence rate of
0.93 % showed the minimum abundance in A. persicus spawners. On the basis of this study the
digestive tract parasite Skrjabinopsolus semiarmatus with a prevalence rate of 77.78 % showed the
maximum abundance and Amphilina foliacea and Eustrongylides excisus with a prevalence rate of
2.78 % showed the minimum abundance in A. stellatus spawners. The relationship between weight of spawners and weight of eggs harvested was studied with prevalence of digestive tract parasites. No
parasitical and bacterial infection was observed in the 100 sturgeon larvae examined. Examination of sturgeon fingerings in the two hatcheries in the middle and again at the end of the
rearing period showed no signs of bacterial and fungal infections.
In the parasitical examination of sturgeon fingerlings studied Triclodina and Diplostomum were
identified. Percentage incidences of Diplostomum in the Shahid Beheshti hatchery was 4.97 % and
that in the Dr. Yousefpour hatchery was 10.09 %. The percentage incidences of Triclodina in the
Shahid Beheshti and Yousefpour hatcheries were 46.68 % and 70.76 %, respectively. However no
Diplostomum infections were observed in the 113 A. stellatus specimens examined in the Shahid
Beheshti hatchery. Results obtained from this study indicate that A. stellatus specimens from the Dr. Yousefpour hatchery showed higher prevalence to Triclodina as well as Diplostomum infection as
compared to the A. stellatus studied in the Shahid Beheshti hatchery. Monitoring the hygienic
conditions in the two hatcheris under study during mid-rearing period and at the end of the rearing
period revealed an increase in prevalence rate and intensity of Triclodina and Diplostomum infection
at the end of the rearing period. Examination of pectoral fin of sturgeon fingerlings indicated higher
incidences of pectoral fin deformities in fingerlings studied in the Shahid Beheshti hatchery than in the
Dr. Yousefpour hatchery.
In 2002 release of fingerlings started on 15.06.2002 at the Shahid Beheshti hatchery and on
8.9.2002 at the Dr. Yousefpour hatchery. Totally 4809554 fingerlings were released into the Sepidrud
River. Totally 2889462 fingerlings were released from 31 earthen ponds (2 hectares) at the Shahid
Beheshti hatchery starting from 17.6 2002 to 21.7.2002 out of which 2563159 fingerlings belonged to
A. persicus that comprised 88.7 % of the total abundance with a mean weight of 5 g and mean length
of 10.9 cm, 324789 fingerlings belonged to A. stellatus that comprised 11.2 % of the total abundance
with a mean weight of 6.9 g and mean length of 16.2 cm, 1514 fingerlings belonged to A. nudiventris
comprising 0.1 % of the total abundance with a mean weight of 12.9 g and a mean length of 14.5 cm. Out of the total number of fingerlings released 74.5 % of A. persicus, 98 % of A. stellatus and 100 % of
A. nudiventris were above 3 g per fish in weight. The survival rate of reared fishes was 45.47 % for A. persicus 0.89 % for A. nudiventris. As the exact number of A. stellatus larvae introduced to the rearing
ponds was not known the survival rate for this species was not estimated. In A. persicus specific
growth rate (3.36) was very low while condition factor (0.41) was moderate. In A. nudiventris growth
rate (3.37) and condition factor (0.41) were moderate.
About 1920092 fingerlings were released from the Dr. Yousefpour hatchery starting from
15.06.2003 to 08.09.2003 of which 1895948 fingerlings belonged to A. persicus that comprised 98.8 %
of the total number with a mean weight of 3.4 g and a mean length of 9.4 cm, 24144 fingerlings
belonged to A. stellatus comprising 1.3 % of the total number with a mean weight of 7.5 g and a mean
length of 11.7 cm
Out of the total number of fingerlings released 43.7 % of A. persicus and 31.7 % of A. stellatus
fingerlings were above 3 g per fish in weight. The survival rates of the reared fishes were 24.2 % for A. persicus and 14.6 % for A. stellatus. In A. persicus the growth rate (2.99) was low while condition
factor (0.38) was moderate. In A. stellatus the growth rate (3.06) and condition factor (0.30) were low. Significant differences (P<0.05) were observed on comparing condition factor (F=4.573), survival
rates (F=20.971) and rearing period (F=5.038) in A. persicus in the two hatcheries. Therefore A. persicus fingerlings released from the Shahid Beheshti hatchery showed better survival rates and
attained the maximum mean weights in a shorter rearing period, whereas fingerlings released from Dr. Yousefpour hatchery were in a better state regarding condition factor. |
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