Combined influence of temperature and salinity on oxygen consumption of the larvae of the pink shrimp, Palaemon serratus (Pennant) (Crustacea, Decapoda, Palaemonidae)

Aquaculture, 86 (1990) 77-92 Elsevier Science Publishers B.V., Amsterdam -

77 Printed in The Netherlands

Combined Influence of Temperature and Salinity on Oxygen Consumption of the Larvae of the Pink Shrimp, Palaemon serratus (Pennant) (Crustacea, Decapoda, Palaemonidae) HIROKO YAGI, HUBERT J. CECCALDI and RAYMOND GAUDY Centre d’Oc6anologie de Marseille, Station marine d%ndoume, F 13007 Marseille (France) (Accepted 7 July 1989 )

ABSTRACT

Yagi, H., Ceccaldi, H.J. and Gaudy, R., 1990. The combined effects of temperature and salinity on the oxygen consumption of the larvae of the pink shrimp, Palaemon serratus (Pennant) (Crustacea, Decapoda, Palaemonidae). Aquaculture, 86: 77-92. The oxygen consumption of the six successive zoeal stages of Pulaemon serrutus reared in 30 different combinations of temperature and salinity was measured. Oxygen consumption per individual, R, increased with the age (or the dry weight, W) of the larvae according to a power function R = a. W b, but no significant relationship was found between the specific respiration, R ’ (respiration rate per dry weight unit ) , and the dry weight of successivelarvalstages.Nevertheless,

highestrateswerealwaysobservedin the Z IV, for all temperatureand salinityconditions.These maximawereprobablyrelatedto largenutritionalchangesoccurringat thisperiodof development. TemperatureaffectedR’ according to a linear function R’ = a’ + b’ - T. Qlovalues varied between 1.50 and 2.58 according to the larval stage and the salinity, except for the Z I at the lowest salinity where a very high value of 5.89 was recorded. The respiration rate decreased at the lowest and highest salinity values. The salinity effect on metabolic rates is described by a quadratic equation R’ = a” + b” *S+ C-S’. The combined effect of temperature and salinity on the respiration of the six successive larval stages is illustrated using tridimensional models. Maximal respiration rates were recorded at salinities between 25%0 and 31%0 and at the highest temperature (29°C).

INTRODUCTION

The physiology of poikilotherms depends, in nature, on a number of factors acting in synergy. Coastal marine organisms are confronted with greater temporal and spatial fluctuations of environmental conditions than pelagic organisms. For most shrimps, the biological cycle includes a marine phase among the first stages of development, then an estuarine or brackish phase for the postlarvae and the juveniles. Following that, the individuals continue their

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0 1990 Elsevier Science Publishers B.V.

78

H. YAGI ET AL.

development and their adult life in marine waters. It thus appears that the degree of tolerance towards environmental factors differs according to the age of the individuals considered. In aquaculture, successful production depends to a large extent on the rate of survival of the younger stages. It is therefore important to determine the most favourable conditions of rearing for each stage. This optimum can be determined directly from the analysis of mortality and growth rates. Another approach, more analytic, consists of evaluating, for each larval stage, the intensity of respiratory metabolism. This is, in effect, a good indicator of the general physiological activity of organisms, as it takes into account the energy needs necessary for osmotic regulation. The effect of combinations of temperature and salinity, two parameters whose impact on metabolism appears most significant, was examined in a previous study of the larval growth of Pdaemon serrutus (Yagi and Ceccaldi, 1984). In this paper we give the results of experiments concerning the effect of these factors on the variations in respiratory metabolism of the first larval stages of the same species. MATERIAL AND METHODS

Eggs originated from females obtained off the coasts of Brittany and, after hatching, the larvae were reared in the laboratory until the stages used for the experiments. The larvae were cultured in 40-l containers, at a temperature of 17-21 ‘C and at 30-32%0 salinity; they were fed on nauplii of Artemia salina during the whole of their larval life, this diet being supplemented by minced mussel meat from the second day of the zoeal III stage. When they reached the stage necessary for experimentation, the larvae were transferred to containers filled with water at different temperatures (13, 17,21, 25 and 29°C) and salinities (13, 19, 25, 31,37 and 43%0). After 2-3 h of acclimation in these new conditions, the zoea were placed in 20-ml test tubes filled with water of a temperature and a salinity identical to those of their acclimation environment. Five to ten individuals (according to their stage; determined by examination through a magnifying glass) were placed in each tube. For each combination of temperature and salinity, three to six tubes with larvae and three tubes without larvae (controls) were prepared. The tubes were hermetically closed and placed in thermoregulated containers for at least 8 h; this time period was prolonged at low temperatures, but never beyond 24 h. The observed vitality of the organisms after incubation suggests that the larvae tolerate confinement (during the experiments) quite well. After incubation, the respiration of the larvae was estimated from the differences in the oxygen content between the experimental tubes and the controls (oxymetre YSI model 57); the duration of incubation and the weight of the larvae were taken into account. Weight was estimated from the dry weight, after dehydration in an oven; a Cahn electrobalance (10 ,ug precision) was used for weighing. The relationships between

OXYGEN CONSUMPTION BY LARVAE OF PALAEMON

79

SERRATUS

respiration, the weight of the larvae, temperature and salinity were calculated separately for each level of salinity and temperature. The validity of the corresponding regression equations was verified by variance analysis. RESULTS

Relationship between respiration and the weight of larval stages Oxygen consumption per individual, R (~1 h-l ind-l), increased according to age or the dry weight of the larvae W (pug) for all combinations of temperature or salinity (Fig. 1). This increase, described by the relationship R = a- wb,

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80

H. YAGI ET AL.

is more pronounced at higher temperatures. The values of a and b, of the correlation coefficient r and the level of significance are indicated in Table 1 for each combination of factors. From the mean values of the dry weight of the different larval stages (Table 2)) the respiration measurements were expressed per unit of dry weight (speTABLE

1

Relationship between oxygen consumption per individual (R, ~1 h-r ind-r ) and dry weight ( W; pup). Value of coefficients a and b of the relationship R = a* W b and of the correlation coefficient r Temperature

Salinity

a

b

r

Level of significance

1.82*10-5 8.47*10W4 4.60*10-4 1.04.10-3

1.67

0.906 0.906 0.941 0.981

0.05 0.05 0.01

%0

(“C) 13

13 19 25 31 37 43

17

13 19 25 31

21

29

0.001 0.001

1.03

0.983 0.894

1.15.10-3 1.99.10-a 1.12.10-3

0.97

0.910

0.05

0.90 1.02

0.956 0.959

0.01

1.91*10-3

0.92 1.13 1.10

0.950

0.01 0.01

0.967 0.960

0.01 0.01

0.916 0.956

0.05 0.01 0.01

37 43

5.57.10-4 5.69*10W4

13

7.41.10-4 1.02.10-3

1.12

0.05

1.03*10-a 1.36.10-3

1.08 1.09 1.04

37 43

1.86.10-3 2.50*10-3

0.97 0.88

0.958 0.967 0.958 0.942

13 19 25 31

9.89.10-4 1.00*10-3 1.94*10-3 2.83*10-3

1.10 1.12 1.00 0.92

0.947 0.956 0.962 0.966

0.01 0.01 0.01 0.01

37 43

2.90.10-a 2.68-10-3

0.89 0.90

0.964 0.973

0.01 0.01

13 19 25 31 37 43

1.17.10-a 2.32.10-3 3.65.10-3 2.56*10W3 2.22*10-3 3.13.10-3

1.04 0.98 0.91 0.97 0.98 0.90

0.953 0.959 0.977 0.990 0.994 0.973

0.01 0.01 0.001 0.001 0.001 0.01

19 25 31

25

2.51.10-4 5.84.10-4

1.00 1.13 0.97 1.22

0.01 0.01 0.01

OXYGEN CONSUMPTION BY LARVAE OF PALAEMON

SERRATUS

81

TABLE 2 Dry weight of the larval stages of Palaemon serratus Stage

Dry weight bg)

Stage

Dry weight (pug)

ZI z II z III

71.90 f 2.13 110.66 k 2.97 148.06 + 4.77

ZIV zv ZVI

169.20 k 13.88 244.37 k 17.82 341.73 k38.29

cific respiration: R’ (~1 h-l g-‘) for all the combinations of factors (Fig. 2). There appears to be no significant relationship between R’ and W, but in most cases, the highest value of R’ was observed at the zoeal IV stages while the lowest value corresponded to the following stage. We also, quite frequently, noted that metabolism, after a reduction at the zoeal V stage, increased during the last stage. Relationship between respiration and temperature The relationship between specific respiration and temperature is linear (R’ =a’ + b’ *T) for all values of salinity (Fig. 3). The parameters a’ and b’ of this equation, the correlation coefficient r and the significance level are indicated in Table 3 for all combinations of factors. During the first stage of development, for the range of temperatures 13-29” C, and the lowest salinity, the value of Ql,, (5.89) shows a very high sensibility to temperature variations. Relationship between respiration and salinity The relationship between R’ and salinity, S, is expressed by a polynomial equation of the type R’ =a” +b”*S+c*S2, for all temperatures (Fig. 4). The values a”, b”, c and the correlation coefficient r are indicated in Table 4. The results show that respiration is lower in conditions of low and high salinity and that this tendency is more pronounced the higher the temperature. Combined influence of temperature and salinity on specific respiration The results obtained for the various larval stages are given in Fig. 5 in the form of three-dimensional block diagrams where the horizontal axes represent temperature and salinity and the vertical one oxygen consumption per unit of dry weight. The effect of the factors was tested by an ANOVA which, in all cases, indicated a significant effect of the parameters temperature and salinity. Thus, respiration has been demonstrated (Fig. 5) to depend on the combined action of temperature and salinity. Its maximum value always corresponds to the maximum temperature of the experiment ( 29 aC ) and to a mean

H. YAGI ET AL

82

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Fig. 2. Oxygen consumption per unit of dry weight of the larvae of Pa&xenon serratus at different temperatures and salinities: (a) temperatures 13-21°C; (b) temperatures 25 and 29°C.

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serrates

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84 TABLE

H. YAGI ET AL.

3

Relationship between oxygen consumption per unit of dry weight (R’; ~1 h-i g-i) and temperature (T, “C) for the larvae of Pulaemon serratus. Values of the coefficients a’ and b’ of the relationship R’ = a’ + b’ *Tand of the correlation coefficient r. Values of Q10 for the temperature range 13-29°C Stage

Salinity

a’

VJo) ZI

z II

0.965 0.941 0.961 0.983

0.05

5.89 1.85 2.10

114.00 75.9 107.7 75.4

37 43

- 503.6

91.1 85.2

0.922 0.963

0.05 0.01

50.8 76.3

0.992 0.978

0.01 0.01

86.3

0.975 0.984

0.01 0.01

1.95 1.95 1.87

0.978 0.994

0.01 0.001

1.97 1.95

0.996

0.01

- 246.8 - 206.2

108.0 83.2 91.8 84.4

0.993 0.975 0.997

0.001 0.01 0.001

2.58 1.65 1.78

37 43

- 103.2

74.6

134.7

59.0

0.993 0.979

0.001 0.01

13 19 25 31

-463.3 181.8 - 130.3 - 194.1

105.3 79.8 101.6

0.972 0.946 0.989

22.9 - 262.2

0.983 0.926 0.970

2.06 1.50 1.64 1.80

37 43

98.4 78.3

0.05 0.05 0.01 0.01 0.05 0.01

1.67 1.83

13

- 578.8 - 148.0

2.57 1.83

13 19

13 19 25

- 540.5 1.1 -216.4 - 303.4 - 172.4 - 370.5 - 395.8

- 769.2 - 119.1

86.0 84.7 82.3

88.2 74.2

0.994 0.993

0.05 0.01 0.01

1.68 2.08 2.04 1.77

1.75 1.77 1.53

- 449.4

61.6 84.1

0.985

0.01 0.001 0.01

31 37 43

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85.7 79.4 77.0

0.972 0.949 0.995

0.01 0.05 0.001

1.96 1.96 2.39

13 19 25 31 37 43

- 450.8 - 375.7 149.1 151.6 318.5 185.1

99.6 101.4 74.7 68.2 56.7 50.7

0.991 0.995 0.983 0.967 0.946 0.975

0.01 0.001 0.01 0.01 0.05 0.01

2.01 1.88 1.58 1.62 1.55 1.50

19 25

ZVI

Q10

- 89.4 - 682.3 -44.6

31

zv

Level of significance

- 1135.4

31 37 43

z IV

r

13 19 25 31

25

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b’

1.99

OXYGEN CONSUMPTION BY LARVAE OF PALAEMON

13'C

85

SERRATUS

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86

H. YAGI ET AL.

salinity of either 19,25 or 31 %o. Its minimum value always corresponds to the lowest temperature (13” C) and to an extreme salinity (13%0 or 43%0 ) . DISCUSSION

In the relationship respiration per individual-weight of the larvae, the value of the b coefficient ranged between 0.89 and 1.67. If the highest value, which corresponded to conditions (13”C, 13%0) which are not very favourable for

OXYGEN CONSUMPTION BY LARVAE OF PALAEMON SERRATUS

3000

87

(b)

1

10

20

30

“C

Fig. 5. Three-dimensional models of the influence of combinaltions of temperature and salinity on the consumption of oxygen per unit of dry weight of the larvae of Palaemon serratus: (a) stages Z I-Z III; (b) stages Z IV-Z VI.

the survival of the larvae, is ignored, the value of b, in general, ranged between 0.67 (“surface law”; Von Bertalanffy, 1957) and 1 (proportionality with weight). Values of this order are cited for various larvae of decapod crustaceans: Homarus americanus (Logan and Epifanio, 1978)) Menippe mercenaria (Mootz and Epifanio, 1974)) Emerita talpidia (Schatzlein and Costlow, 1978)) Penaeus monodon and P. stylirostris (Gaudy and Sloane, 1981). Values higher

H. YAGI ET AL.

88 TABLE 4

Relationship between oxygen consumption per unit of dry weight (R’; ,~l h-i g-l) and salinity (S; %o) for the larvae of Palaemon serratus. Values of the coefficients a”, b” and c of the relationship R’ =a” +b”-S+e*S’ and of the correlation coefficient r Stage

Temperature (“Cl

a”

b”

c

r

ZI

13 17 21 25 29

- 1026.276 220.579 1062.588 799.021 -313.585

130.408 91.697 16.822 74.844 190.848

-2.219 - 1.891 -0.125 - 1.238 -3.387

0.867 0.991 0.606 0.896 0.831

z II

13 17 21 25 29

348.190 84.928 - 407.971 91.404 -462.573

27.334 80.875 147.599 117.379 169.856

- 0.438 - 1.384 -2.562 - 1.958 - 2.605

0.867 0.893 0.933 0.899 0.973

z III

13 17 21 25 29

231.557 877.754 700.477 1782.395 496.464

48.741 24.694 75.567 22.144 136.422

-0.815 - 0.468 - 1.376 - 0.589 -2.516

0.628 0.869 0.814 0.938 0.947

z IV

13 17 21 25 29

291.905 753.927 1544.369 1187.396 - 1007.461

67.942 53.752 40.426 93.250 243.078

- 1.316 - 1.047 - 0.778 - 1.834 -4.016

0.787 0.952 0.985 0.957 0.864

zv

13 17 21 25 29

- 385.531 67.278 - 26.966 829.425 - 997.277

78.878 61.011 96.374 49.131 201.671

-

1.380 1.056 1.654 0.923 3.220

0.971 0.935 0.978 0.927 0.994

ZVI

13 17 21 25 29

514.370 398.622 1196.306 1724.378 690.226

35.496 77.256 53.542 42.410 122.980

- 0.660 - 1.442 - 1.178 - 1.106 -2.423

0.817 0.974 0.907 0.947 0.828

than 1 are more rarely encountered in the literature: Homarus americanus (Capuzzo and Lancaster, 1979). Values for Cancer irroratw, at 10°C and 30%0 salinity (Johns, 1981) appear, according to this last author, to indicate conditions of physiological stress close to the thermal limits of the distribution of

OXYGEN CONSUMPTION BY LARVAE OF PALAEMON SERRATUS

89

the species; this could also be the case for the maximum values of b observed for the larvae of Pdaemon serrcztus at 13°C for five salinities out of six. However, the frequency of values close to 1 for the other temperatures examined shows that the value for this parameter, otherwise not significantly affected by variations in temperature and salinity, is not the norm for the species considered. Calculated by unit of weight of dry matter, the metabolism is independent of the biomass of the larval stages; this result is similar to that obtained for the larvae of Cancer irroratus (Johns, 1981) and of Libinia emarginata (Schatzlein and Costlow, 1978). It varies from what is usually observed for adult crustaceans where the relationship specific respiration-weight is usually described, in logarithmic coordinates, by a linear relationship with a negative slope. According to Johns (1981) , if important morphological or physiological changes do not occur during the larval stages, metabolic demand per unit of weight must remain unchanged throughout this period. We have noted lower values for the stage Z V and, very often, a maximum at stage Z IV; this latter stage is that of an important physiological modification corresponding to a shift towards a more carnivorous diet expressed by a sudden increase in the proteasic activity (Van Wormhoudt, 1973). This activity subsequently marks a step in stage Z V. The differences found for stage Z IV can be related to such a physiological modification; this is not the same for the minimal values which are nearly always found at stage Z V. These low values perhaps indicate a new state of physiological equilibrium brought about by acclimation of the organism to its new diet. In the relationship metabolism-temperature, there is no marked tendency for the rate of respiration, at temperatures between 25°C and 29”C, to slow down (except for assays with a 13%0 salinity where the combination of low salinity and high temperatures bring about a decrease in respiration). Thus, the thermal range which is compatible with undisturbed physiology of the organism ( Qlo constant) appears to be vast and oriented towards high temperatures. In fact, according to Reeve (1969)) the best conditions of culture for the larvae of Pcduemon serratus correspond to the thermal interval 22-26’ C whereas this optimum is situated at 22°C for adults (Richard, 1978). Furthermore, the values of QIO,most of which are lower than 2, indicate a certain eurythermia (Schlieper, 1952) which is observed for salinities between 19%o and 43%0. This represents an advantage for the migration of the larvae from a marine environment to a coastal one where the ecological parameters are more unstable. A similar observation was made for Pcduemonetes vulgaris (McFarland and Pickens, 1965). The decrease in respiration either side of an optimum, observed for the larvae of Pdaemon serratus, is a fairly common phenomenon with marine invertebrates. This metabolic reaction corresponds to type 4 defined by Kinne (1962). However, the opposite (increase either side of the optimum; type 3 of Kinne, 1962 ) is also observed for certain crustaceans

90

H. YAGI ET AL.

such as, for example, the adults of Crangon vulgaris or the juveniles of Penaeus indict (standard metabolism, Kutty et al., 1971). Metabolism can be reduced in accordance with increases in salinity for all the range tested as for Carcinus maenas (type 2). Finally, respiration can remain stable whatever the salinity, as for the crab Eriocher (type 1); this, intuitively, appears to correspond to optimum conditions of adaptation to an environment with fluctuating salinities. Jones (1974) thus shows that the isopod Idotea chelipes, from a brackish habitat, presents stable rates of metabolism whereas the marine species of the same genera I. neglecta and I. emarginata show a decreased metabolism for extreme values of salinity; this is in accordance with our observations for the larvae of Palaemon serratus. The importance of acclimation to salinity also appears for the juveniles of the crab Callinectes sapidus whose metabolism is constant (type 1) after acclimation but corresponds to type 3 for non-acclimated individuals. For the larvae of Palaemon serratus it is possible that the results concerning the type of metabolic reaction correspond to insufficient acclimation. In fact, acclimation was effected on individuals at fixed stage, isolated before experimentation, and not for the total period of their development. However, it is possible that the relative sensitivity of metabolism of the zoeae to changes in salinity is linked to their marine phase; the migration to the lagoon environment occurs mainly at the postlarval stage. It is, in fact, during this stage that euryhalinity, expressed by a metabolic reaction only slightly affected by changes in salinity, appears as a certain advantage; this has been observed for the postlarvae of two species of the genus Penaeus (Gaudy and Sloane, 1981). The zoeae of Palaemonserratus, therefore, present eurythermia (with a preference for high temperature) which is not accompanied by a particular euryhalinity. These characteristics are in accordance with the marine habitat of these stages during a season (spring) when thermal conditions can change rapidly. Under laboratory rearing conditions, cultures could be optimized by taking into account the thermal and haline conditions most favourable to the physiology of each different stage of the species. It must be stressed that the analysis of factors which can play a role should not be limited to temperature and salinity; other parameters, light and oxygen content in particular, could also have a significant effect. In addition, factors linked to experimental conditions, such as over-stocking, accumulation of metabolites, wall effect (related to the size of the aquariums or of the oxygen bottles), which are inevitably artificial, could be influential. In general, oxygen consumption is high during stage Z IV. This observation may be linked with the fact that, at this particular stage of larval development, the number of tubes of the hepatopancreas suddenly multiplies (Richard, 1978). This anatomic change, which is accompanied by a sudden increase in the number of cells of the hepatopancreas, corresponds to an important increase in the enzymatic proteasic activities. It is also at this moment that the larvae begin

OXYGEN CONSUMPTION BY LARVAE OF PALAEMON

SERRATUS

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to consume a diet which is richer in animal protein, and change the type of feeding, both in nature and in laboratory cultures. Their nitrogenous excretion is also greatly increased. Furthermore, a second increase in respiration is observed at stage VI. It seems to correspond to the phase of morphological metamorphosis, which was also linked to a modification in behaviour. Larvae are pelagic and swim with their abdomen uppermost: the first postlarvae become benthic and orientate their bodies horizontally. At this moment they acquire an internal anatomy which is close to that which characterizes the adults. On the other hand, the fact that oxygen consumption is maximal at a salinity of between 25%0 and 30%0 can be explained by a greater physiological activity linked to the utilization of food by the larvae. In fact, it is at these mean salinities that the energy needs for osmotic regulation appear to be the lowest and that growth is the greatest (Yagi and Ceccaldi, 1984).

REFERENCES Capuzzo, J.M. and Lancaster, B.A., 1979. Some physiological and biochemical considerations on larval development of the American lobster Homarus americanus Milne Edwards. J. Exp. Mar. Biol. Ecol., 40: 53-62. Gaudy, R. and Sloane, L., 1981. Effect of salinity on oxygen consumption in post larvae of the penaeid shrimps Penaeus monodon and P. stylirostris without and with acclimation. Mar. Biol., 65: 297-301. Johns, D.M., 1981. Physiological studies on Cancer irroratus larvae. II. Effects of temperature and salinity on physiological performance. Mar. Ecol. Progr. Ser., 6: 309-315. Jones, M.B., 1974. Survival and oxygen consumption in various salinities of three species of Zdotea (Crustacea, Isopoda) from different habitats. Comp. Biochem. Physiol., 48: 501-506. Kinne, O., 1962. Physiology of estuarine organisms with special reference to salinity and temperature; generai aspects. In: G.H. Lauff (Editor), Estuaries. American Association for the Advancement of Science, Washington, DC, pp. 5X-540. Kutty, M.N., Murugapoopathy, G. and Krishnan, T.S., 1971. Influence of salinity and temperature on the oxygen consumption in young juveniles of the Indian prawn Penaeus indicus. Mar. Biol., 11: 125-131. Logan, D.T. and Epifanio, C.E., 1978. A laboratory energy balance for the larvae and juvenile of the American lobster Hom.arus americanus. Mar. Biol., 47: 381-389. McFarland, W.N. and Pickens, P.E., 1965. The effect of season, temperature and salinity on standard and active oxygen consumption of the grass shrimp, Palaemonetes vulgaris (Say). Can. J. Zool., 43: 571-585. Mootz, C.A. and Epifanio, C.E., 1974. An energy budget for Menippe mercenaria larvae fed Artemia nauplii. Biol. Bull. Mar. Biol. Lab., Woods Hole, 146: 44-55. Reeve, M.R., 1969. Growth, metamorphosis and energy conversion in the larvae of the prawn Palaemon serratus. J. Mar. Biol. Assoc. U.K., 49: 77-96. Richard, P., 1978. Influence de la tempkrature sur la croissance et la mue de Palaemon serratus en fonction de leur taille. Aquaculture, 14: 13-22. Schatzlein, F.C. and Costlow, J.D., Jr., 1978. Oxygen consumption of the larvae of the decapod crustaceans Emerita talpoida (Say) and Libinia emarginata Leach. Comp. B&hem. Physiol., 61A: 441-450.

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Schlieper, C., 1952. ijber die Temperatur-Stoffwechselrelation einiger eurythermer Wassertiere. Verh. Dtsch. Zool. Ges., Suppl. 16,5: 267-272. Van Wormhoudt, A., 1973. Variation des proteases, des amylases et des proteines solubles au tours du developpement larvaire chez Palaemon serrates. Mar. Biol., 19: 245-248. Von Bertalanffy, L., 1957. Quantitative laws in metabolism and growth. Q. Rev. Biol., 32: 217231. Yagi, H. and Ceccaldi, H.J., 1984. Influence combine des facteurs temperature et salinitk sur le metabolisme et la croissance larvaire de la crevette rose Palaemon serratus (Pennant) (Crustack, Dkcapode, Palaemonide). Aquaculture, 37: 73-85.