Carp nutrition
61
most
of P is lost in feces at maximum rate of 80 mg P kg—1 day—1 (Sternik,
1983), This suggest that ? availability from food is critical in fulfilment
of P needs.
D.
Fatty acid requirements
Fingerling carp of 2,5 g was reported to show no essential fatty acid
(EPA) deficiency signs even though fish were fed a lipid—free diet for 22
weeks
(Watanabe et al., 1975a). But is was found that carp would show the EFA
deficiency symptoms when fish of 0.09 g were conditioned on a lipid—free diet
for 6 weeks and then switched to EFA deficient diet (Watanabe et al. 1975b).
Takeuchi and Watanabe (1977) demonstrated clear difference in growth
rate by feeding diets containing various fatty acids to carp of 0.5 g after
the 6—week conditioning° From these studies, they concluded that mixture of
1%
18:2n—6 and 1%
18:3n—3 could satisfy EFA requirements, and were superior
to
either fatty acid fed separately. Also highly unsaturated fatty acids such
as
20:5n—3 and 22:6n—3 were more efficient than linoleic and linolenic acids.
E.
Energy requirements and utilisation
Inevitable losses
Data arising from starvation experiments have been considered in the
past to be approximate values for maintenance. According to definition
ver, maintenance feeding is equivalent to nutrient — energy equilibrium. Expe—
rimental results conducted at starvation level can set up the following equa—
tion for the calculation of heat production (Q
=
13.78 kJ g02“1) dependant
upon water
temperature :
OX
—0.8 —1
°
2
y =
(Heat kJ kg
d
) = —11.93 + 2.02 X ( C) r 0.996
Maintenance requirement of ME
The energy level required for maintenance depends upon water temperature
and quality, type and weight of the fish, activity, quality of the diet and
the chemical composition of the experimental animal. There are only few re—
sults dealing with maintenance requirements derived from feeding experiments
(Huisman, 1976; Becker et al 1983; Schwarz and Kirchgessner, 1984; Becker,
1984). Table 4 is a summary of data from the literature for starvation and
maintenance metabolism. These results indicate that at present no universal—
ly applicable measurements comparable to those available for the maintenance
of domestic animals are aVailable for carp.
It
is also not clear whether the
changes in the rate of metabolism follow an allometric or an isometric pat—
tern.
Experimental results of Becker et al. (1983) and Becker (1984) on carp
in weight ranges of 25—200 %
and 70—1600 g differ considerably from each
other, Viz. 22.7 kJ ME kg0° 91d‘] and 32.7 kJ ME kg”0o799d_1 respectively.
“…
Mathematically one can arrive at the partial efficiency of BŒ for main—
tenance
(Km—value) as follows :
K
_
……
m
_
ME.required
In our own experiments (Becker, 1984) the maintenance requirements of
ME and then the starvation loss (6 weeks) using the same fish with body wei—
8hts between 70—1600 g were established.
61
most
of P is lost in feces at maximum rate of 80 mg P kg—1 day—1 (Sternik,
1983), This suggest that ? availability from food is critical in fulfilment
of P needs.
D.
Fatty acid requirements
Fingerling carp of 2,5 g was reported to show no essential fatty acid
(EPA) deficiency signs even though fish were fed a lipid—free diet for 22
weeks
(Watanabe et al., 1975a). But is was found that carp would show the EFA
deficiency symptoms when fish of 0.09 g were conditioned on a lipid—free diet
for 6 weeks and then switched to EFA deficient diet (Watanabe et al. 1975b).
Takeuchi and Watanabe (1977) demonstrated clear difference in growth
rate by feeding diets containing various fatty acids to carp of 0.5 g after
the 6—week conditioning° From these studies, they concluded that mixture of
1%
18:2n—6 and 1%
18:3n—3 could satisfy EFA requirements, and were superior
to
either fatty acid fed separately. Also highly unsaturated fatty acids such
as
20:5n—3 and 22:6n—3 were more efficient than linoleic and linolenic acids.
E.
Energy requirements and utilisation
Inevitable losses
Data arising from starvation experiments have been considered in the
past to be approximate values for maintenance. According to definition
ver, maintenance feeding is equivalent to nutrient — energy equilibrium. Expe—
rimental results conducted at starvation level can set up the following equa—
tion for the calculation of heat production (Q
=
13.78 kJ g02“1) dependant
upon water
temperature :
OX
—0.8 —1
°
2
y =
(Heat kJ kg
d
) = —11.93 + 2.02 X ( C) r 0.996
Maintenance requirement of ME
The energy level required for maintenance depends upon water temperature
and quality, type and weight of the fish, activity, quality of the diet and
the chemical composition of the experimental animal. There are only few re—
sults dealing with maintenance requirements derived from feeding experiments
(Huisman, 1976; Becker et al 1983; Schwarz and Kirchgessner, 1984; Becker,
1984). Table 4 is a summary of data from the literature for starvation and
maintenance metabolism. These results indicate that at present no universal—
ly applicable measurements comparable to those available for the maintenance
of domestic animals are aVailable for carp.
It
is also not clear whether the
changes in the rate of metabolism follow an allometric or an isometric pat—
tern.
Experimental results of Becker et al. (1983) and Becker (1984) on carp
in weight ranges of 25—200 %
and 70—1600 g differ considerably from each
other, Viz. 22.7 kJ ME kg0° 91d‘] and 32.7 kJ ME kg”0o799d_1 respectively.
“…
Mathematically one can arrive at the partial efficiency of BŒ for main—
tenance
(Km—value) as follows :
K
_
……
m
_
ME.required
In our own experiments (Becker, 1984) the maintenance requirements of
ME and then the starvation loss (6 weeks) using the same fish with body wei—
8hts between 70—1600 g were established.