240
Æquæuluæ of Cyprinids
red with the fish fed with mixed food showed an additive effect È
A) Factor—level of dry food : dry food particles/dm
1000
500
0
B)Zooplankton
“Ë3 libitum"
12,7
11,0
9,7
restricted
9,0
8,2
6,2
nil
3,1
2,6
0,9
This phenomenon appears 3 times on 4. If we add the final weight of fish fed
with dry food anly and that of those fed with zooplankton we obtain the wei—
ght of fish fed with2mixed
food
:
example : 3,1 mg/fish fed with dry food
at
1000 particles/dm / +9,7 mg (those fed with "ad libitum" level of zooplan—
kton) = 12,8 mg which is very close to 12,7 mg. Therefore the test diet may
be used as
a
substitute for zooplankton if it is lacking. The results of
these experiment suggest, that if the time of feeding with dry food was
extended to
12 h/i.e. as long as the time of feeding with zooplankton/, the
growth of each group would be similar, but experimental revision is required.
OPTIMIZING THE BIOTECHNIQUES OF INTENSIVE CARP FINGERLING REARING. J
.
SZUMIEC,
FÆ/3h CuÆ/Cu/œ EXp…mcMa£ Station Go£yAz, 43—422
POLAND.
The investigations carried out in 1981—85 aimed at successively defining
the
influence of stock density, origin of the stock, pond fertilization and
feed protein content. The experiments, each variant of which was repeated
three
times, were carried out in a serie of 24 ponds. During the experiments,
pond environment and reared fish were closely observed. Two levels of stock—
ing density were always used : 120 000 and 150 000 or 90 000 and 120 000 Co/
ha.
Production was better, as a rule, with lower stock. In 1981, with uniform
pond fertilization and fish feedingn growth, survival and feed conversion
rates
were
almost
1002 higher with hybrids of Polish and Hungarian carp
than.with their inbred pure lines.
1982—83 being exceptionally thermally
advantageous (sums of effective carp growth temperature higher than 140 :
9740 and 9830) with uniform fish feeding we compared the effectiveness of
various kinds of fertilization. The fish were fed first on starter containing
50% protein and then on pellets containing 30% protein. Mineral—organic fertilization was slightly better (fish growth 2886 Kg/ha : survival rate 47%
food coefficient 1,83) than mineral or organic fertilization while in non—
fertilized ponds growth was 2674 Kg/ha, survival rate 56% and food coeffici—
ent
2,0. The intensity of fertilization depended on phytoplankton develop—
ment
and water oxygen saturation. One dose contained 67 Kg of ammonium
saltpetre and 47 Kg of superphosphate or 2 1113 of liquid manure per hectare.
The amount of biogenes supplied was generally higher with mineral fertiliza—
tion. The
1985—85 experiments aimed at defining the effect of different diet—
ary protein levels on carp growth with uniform.organic—mineral pond fertili—
zation.
In unfavourable weather conditions in 1984, (the sum of effective
watertemperature 618°) feeding on pellets containing 20,30 and 402 protein,
gave similar results
(average fish growth 1518 Kg/ha, survival rate : 48%;
food coefficient 3,9 but which were higher than those of feeding with pellets
containing 10% protein (1194 Kg/ha, 42%, 4,6 respectively).
Æquæuluæ of Cyprinids
red with the fish fed with mixed food showed an additive effect È
A) Factor—level of dry food : dry food particles/dm
1000
500
0
B)Zooplankton
“Ë3 libitum"
12,7
11,0
9,7
restricted
9,0
8,2
6,2
nil
3,1
2,6
0,9
This phenomenon appears 3 times on 4. If we add the final weight of fish fed
with dry food anly and that of those fed with zooplankton we obtain the wei—
ght of fish fed with2mixed
food
:
example : 3,1 mg/fish fed with dry food
at
1000 particles/dm / +9,7 mg (those fed with "ad libitum" level of zooplan—
kton) = 12,8 mg which is very close to 12,7 mg. Therefore the test diet may
be used as
a
substitute for zooplankton if it is lacking. The results of
these experiment suggest, that if the time of feeding with dry food was
extended to
12 h/i.e. as long as the time of feeding with zooplankton/, the
growth of each group would be similar, but experimental revision is required.
OPTIMIZING THE BIOTECHNIQUES OF INTENSIVE CARP FINGERLING REARING. J
.
SZUMIEC,
FÆ/3h CuÆ/Cu/œ EXp…mcMa£ Station Go£yAz, 43—422
POLAND.
The investigations carried out in 1981—85 aimed at successively defining
the
influence of stock density, origin of the stock, pond fertilization and
feed protein content. The experiments, each variant of which was repeated
three
times, were carried out in a serie of 24 ponds. During the experiments,
pond environment and reared fish were closely observed. Two levels of stock—
ing density were always used : 120 000 and 150 000 or 90 000 and 120 000 Co/
ha.
Production was better, as a rule, with lower stock. In 1981, with uniform
pond fertilization and fish feedingn growth, survival and feed conversion
rates
were
almost
1002 higher with hybrids of Polish and Hungarian carp
than.with their inbred pure lines.
1982—83 being exceptionally thermally
advantageous (sums of effective carp growth temperature higher than 140 :
9740 and 9830) with uniform fish feeding we compared the effectiveness of
various kinds of fertilization. The fish were fed first on starter containing
50% protein and then on pellets containing 30% protein. Mineral—organic fertilization was slightly better (fish growth 2886 Kg/ha : survival rate 47%
food coefficient 1,83) than mineral or organic fertilization while in non—
fertilized ponds growth was 2674 Kg/ha, survival rate 56% and food coeffici—
ent
2,0. The intensity of fertilization depended on phytoplankton develop—
ment
and water oxygen saturation. One dose contained 67 Kg of ammonium
saltpetre and 47 Kg of superphosphate or 2 1113 of liquid manure per hectare.
The amount of biogenes supplied was generally higher with mineral fertiliza—
tion. The
1985—85 experiments aimed at defining the effect of different diet—
ary protein levels on carp growth with uniform.organic—mineral pond fertili—
zation.
In unfavourable weather conditions in 1984, (the sum of effective
watertemperature 618°) feeding on pellets containing 20,30 and 402 protein,
gave similar results
(average fish growth 1518 Kg/ha, survival rate : 48%;
food coefficient 3,9 but which were higher than those of feeding with pellets
containing 10% protein (1194 Kg/ha, 42%, 4,6 respectively).