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Effect of environmental embryonic temperature on larval development of Macrobrachium rosenbergii (De Man)
J. Exp. Mar. Biol. Ecol., 1987, Vol. 114, pp. 39-47
39
Elsevier
JEM 00982
Effect of environmental embryonic temperature on larval development of Macrobrachium rosenbergii (De Man) Gabriel
Gomez
Diaz
Aquaculture Depaninent, Faculty of Applied Biological Sciences, Hiroshima Universiry. Fukuyama,‘Japan
(Received 3 March 1987; revision received 29 July 1987; accepted 3 September 1987) Berried females of Macrobrachium rosenbergii (De Man) from Anuenue stock were allowed to incubate their eggs at three different temperatures (25,29, and 31 “C). The newborn larvae were reared in the laboratory from hatch through completion of the metamorphosis to postlarva in 30 combinations of temperature (22-34 “C) and salinity (O-34 ppt). Survival and stage attainment rates were observed. Multiple linear regression analysis and response surface methodology were used to estimate the response of larvae to these different temperature and saliity combinations. Dissimilarities in the response of zoeae from the three egg incubation temperatures were found. Larvae from eggs incubated at 25 “C during embryonic development showed tolerance to a broader range of temperature and salinity conditions than those incubated at 29 or 31 “C. The response also changed with the ontogeny of the larvae. The zoeae are considered to have undergone acclimation during embryonic development, thus eliciting a different response. Abstract:
Key words: Environmental history; Larval development; Macrobrachium rosenbergi% Palaemonid prawn; Salinity; Temperature
INTRODUCTION
Temperature and salinity are two of the most important environmental factors in marine and brackish water habitats affecting the life processes of crustacean larvae, especially the rates of survival and growth. The combined effects of these two factors have been studied to assess the optimum rearing conditions of a number of decapod larvae (Choudhury, 1970, 1971; Knowlton, 1974; Rochanaburanon & Williamson, 1976; Moreira et al., 1979; Ogasawara et al., 1979; Uno & Yagi, 1980; Yagi 8z Uno, 1981; Yagi 8c CeccaIdi, 1983, 1984; Holtschmit & Pfeiler, 1984; Igarashi et al., 1984; Blaszkowski & Moreira, 1986). To date, there is no information on the combined effect of these environmental factors on development of Mucrobrachium larvae. This paper deals with the evaluation of combined temperature and salinity effects on the zoeal stages of Macrobrachium rosenbergii (De Man) after their incubation at ditTerent temperatures.
Correspondence address: G. Gomez Diaz, Aquaculture Department, Faculty of Applied Biological Sciences, Hiroshima University, 2-17 Midorimachi, Fukuyama 720, Japan. 0022-0981/87/$03.50 0 1987 Elsevier Science Publishers B.V. (Biomedical Division)
40
G.GOMEZ METHODS
AND
DIAZ
MATERIALS
Anuenue broodstock was used for the present experiment. The rearing and feeding of prawns were the same as reported previously (Gomez Diaz & Ohno, 1986). Three females were inseminated by the same male to minimize variations of genetic origin; after mating, each berried female. was allowed to acclimatize to one of the three egg incubation temperatures (25, 29, or 31 “C), by changing the water temperature at the rate of 1 “C every 2 h. Within 1 h after hatching, the zoeae were transferred to l-l beakers and allowed to acclimatize to one of the six experimental salinities (0,6.8, 13.6, 20.4,27.2, and 34 ppt), changing the salinity at a rate of 6.8 ppt per 30 min with the egg incubation temperature unchanged. After salinity acclimation, dupfcate samples of 40 individuals were put into 500-cc culture dishes and these were placed in constant temperature water baths. Then the larvae were allowed to acclimatize to the five experimental temperatures (22,25,28, 31, and 34 “C) by changing the temperature at a rate of 3 ‘C every 2 h. Survival and development stage were recorded on a daily basis; development was calculated as the median number of days required to reach each larval stage, and response surface methodology (Box, 1954, 1956; Box & Youle, 1955; Alderdice, 1972) was used to produce response surface equations from these data. The functional form used was a full quadratic with temperature and salinity as interaction terms. These response surface equations were further expressed in accordance with the formula of a common ellipse (Gomez Diaz, 1987), and from this, the surface area was determined. RESULTS
Differences were found among Anuenue stock zoeae from eggs incubated at the three temperatures. The duration from spawning to hatch was 26, 17, and 16 days for the temperatures of 25,29, and 3 1 ’ C, respectively. According to the survival data (Table I), the larvae from eggs incubated at 29 “C metamorphosed from 25 to 34 ‘C, and a metamorphosis rate higher than 30% was obttied in the range of 28-31 “C and 6.8-27.2 ppt of salinity. In the case of egg incubation at 31 “C, the temperature range to obtain postlarvae was 25-3 1 “C, and metamorphosis rates of > 40% were obtained only at 25 “C and 20.4 ppt, 28 “C and the salinity range of 13.6-27.2 ppt, and 31 “C and 13.6 ppt. However, in the case of egg incubation at 25 “C, the temperature range where the larvae could metamorphose, was shifted to 22-3 1 ‘C, while > 70% metamorphosis was observed in the range of 25-3 1 ‘C and at salinities of 6-8-34 ppt (13.6 and 20.4 ppt only, for the case of 25 “C) (Table I). By means of the response surface analysis, these differences become more obvious. In Fig. 1, the response contours were plotted for 60% attainment to the ninth zoea. This model displays the larval tolerance to wider ranges of salinity in every instance compared to the ranges of tolerance to temperature. The differences in tolerance among the three groups are significant specially in the case of larvae from eggs incubated at
EFFECT OF EMBRYONIC
TEMPERATURE
41
ON MACROBRACHZUM DEVELOPMENT
29 “C where the zoeae are restricted to a limited range of temperature and salinity conditions. This can also be noted in Fig. 2, where the response surfaces are plotted as 30% metamorphosis to postlarva for larvae of each of the three egg incubation temperatures. The larvae from eggs incubated at 3 1 and 25 “C during embryonic development display more tolerance to lower temperatures and more resistance to combined conditions of temperature and salinity than the larvae from eggs incubated at 29 ’ C. This means that larvae incubated at 29 oC have more narrow tolerance limits in respect to temperature and salinity conditions than those of the other two groups.
TABLE I Survival and median number of days to metamorphosis of M. rosenbergii larvae incubated at three temperatures during embryonic development and reared under 30 combinations of temperature-salinity. s (PPt)
22
25
28
31
34
0.0 6.8 13.6 20.4 27.2 34.0 0.0 6.8 13.6 20.4 21.2 34.0 0.0 6.8 13.6 20.4 27.2 34.0 0.0 6.8 13.6 20.4 21.2 34.0 0.0 6.8 13.6 20.4 27.2 34.0
Metamorphosed larva (%)
Median number of days to metamorphosis
Incubation temperature (“C)
Incubation temperature to C)
25
29
31
0.0 0.0 1.5 17.5 18.8 0.0 0.0 41.3 70.0 70.0 53.8 28.8 0.0 66.3 18.8 88.8 81.3 72.5 0.0 51.3 12.5 80.0 76.3 76.3 0.0 0.0 0.0 0.0 0.0 0.0
0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 3.8 1.5 1.5 0.0 45.0 53.8 42.5 46.3 16.3 0.0 30.0 41.3 11.3 35.0 18.8 0.0 0.0 1.3 0.0 0.0 0.0
0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 3.8 43.8 18.8 5.0 0.0 28.8 43.8 57.5 60.0 20.0 0.0 28.8 52.5 37.5 35.0 20.0 0.0 0.0 0.0 0.0 0.0 0.0
25
29
61.0 61.7 52.1 77.0
-
39.8 33.1 31.0 31.5 39.2
49.7 40.0 43.0 52.0
61.5 46.5 39.1 41.5 56.5
25.4 23.1 23.1 23.2 75.8
42.0 32.4 37.4 37.8 41.0
35.8 30.2 34.4 35.3 42.0
21.0 18.1 19.1 19.3 21.1
34.0 28.8 21.0 26.8 34.0
28.9 27.0 29.3 34.5 36.7
27.5
31
G. GOMEZ DIAZ
42
The reduced length of the temperature axes, as seen in Figs. 1-2, indicates that M. rosenbergii zoeae are more restricted by temperature than by salinity conditions. It was found that the response surfaces obtained are ellipsoid in shape for most of the cases (hyperbolae were obtained for the second zoea from eggs incubated at 29 “C)
0
6.6
13.6 SALINITY
20.4
27.2
34
ppt
Fig. 1. Response surfaces estimated as 60% attainment to the ninth zoed stage ofM. rosenbergiilarvae. The numbers in the response contours indicate the egg incubation temperature (“C).
O
6.8
13.6 SALINITY
20.4
27.2
34
ppt
Fig. 2. Estimated response surfaces for 30?,, metamorphosis to postlarva of M. rosenbergii larvae. The number in the response contours indicates the egg incubation temperature (“C).
(Table II). On this basis, a comparison between the response contours for the different larval stages was accomplished by means of the area of ellipsoids (estimated as 30% attainment to each stage) plotted in Fig. 3 against zoeal stage. The first four larval stages have bigger area values that decrease as development progresses. This means that early
TABLE
II
10 11 Pl
i
PI 2 3 4 5 6
:‘:
: 9 10 11 Pl 2 3 4 5 6 I
;
4.1579 22.8368 31.4726 69.4083 84.3401 95.6747 100.5820 101.8910 102.1320 100,755o 96.3106 - 0.1949 27.6589 69.1446 91.6316 93.6479 89.7959 84.3115 81.1767 55.1196 42.8657 42.1145 16.8827 76.2356 75.0758 91.5632 119.1850 118.7180 110.1630 101.5750 67.2888 5 1.6230 49.8659
- 0.07761 - 0.38520 - 0.53403 - 1.23332 - 1.50782 - 1.71941 - 1.80871 - 1.83017 - 1.83185 - 1.80379 - 1.72602 - 0.00003 - 0.47287 - 1.20696 - 1.61865 - 1.65831 - 1.59218 - 1.49293 - 1.43511 - 0.97214 - 0.75392 - 0.74068 - 0.31413 - 1.30613 - 1.29459 - 1.60209 -2.11461 - 2.10627 - 1.95089 - 1.79553 - 1.18541 - 0.9093 1 - 0.87956
=2 8.34234 8.57251 8.31450 7.15482 7.34820 7.53192 7.86694 7.90102 6.60569 5.16047 4.20689 8.47097 7.34206 3.36152 3.05463 3.23193 2.72318 2.77234 2.94017 1.84809 1.69261 1.66692 6.14776 2.96613 2.21957 3.40451 5.23248 5.50833 5.30665 5.16861 3.59545 2.99021 2.88269
c3
CS
0.03626 0.03735 0.03844 0.01880 - 0.01005 - 0.02519 - 0.04394 - 0.51704 - 0.02735 0.00673 0.02351 0.02201 0.07253 0.13135 0.52544 0.0060 1 0.00492 - 0.00121 - 0.09788 0.00508 0.0029 1 0.00183 0.12375 0.50118 0.17158 0.11748 0.2298 1 -0.01111 - 0.01833 - 0.02339 - 0.01240 - 0.00465 - 0.00249
- 0.22342 - 0.23489 - 0.22977 - 0.18089 -0.16715 - 0.16346 - 0.16079 - 0.15742 - 0.14358 - 0.13333 - 0.11765 - 0.21286 - 0.22762 - 0.16685 - 0.10638 - 0.07942 - 0.06292 - 0.06098 - 0.06128 - 0.04939 - 0.04786 - 0.04642 - 0.23705 - 0.16613 - 0.16439 - 0.15762 - 0.14163 - 0.12001 - 0.10843 - 0.10238 - 0.0790 1 - 0.07501 - 0.07389
-
C4
Regression coefficients
Multiple correlation coefficient 0.900265 0.911298 0.906859 0.883407 0.878588 0.887055 0.886063 0.886447 0.892390 0.896824 0.905450 0.881828 0.901684 0.890123 0.849078 0.839871 0.836378 0.838834 0.838262 0.774702 0.730060 0.726832 0.877406 0.881488 0.894046 0.902584 0.891338 0.870033 0.858831 0.858310 0.836601 0.809033 0.809604
C6
- 38.029 - 319.534 - 442.854 - 945.659 - 1145.150 - 1294.440 - 1360.390 - 1379.660 - 1384.580 - 1370.070 - 1310.650 22.954 - 384.556 - 957.139 - 1257.970 - 1284.150 - 1231.230 - 1157.940 - 1117.220 - 760.605 - 593.428 - 582.993 - 205.48 - 1073.25 - 1051.39 - 1269.45 - 1635.74 - 1632.91 - 1519.05 - 1404.05 - 933.93 - 717.54 - 692.58
31.0 30.5 30.5 29.4 28.3 28.1 28.1 28.1 28.3 28.3 28.3 _* 30.9 29.8 28.7 28.3 28.2 28.2 28.2 28.4 28.5 28.5 31.8 30.7 30.2 28.3 27.9 27.1 27.6 27.6 27.7 28.0 28.0
21.0 22.7 22.9 21.8 20.8 21.7 22.0 22.0 20.5 19.0 19.0 2T.o 21.8 21.4 21.4 22.7 22.5 22.2 20.2 18.6 18.5 21.3 20.7 20.6 21.3 21.1 20.9 20.7 20.6 20.4 20.0 20.7
f (“Q
s (PPt)
Centre
Lt., egg incubation temperature; pi, postlarva; *temperature and salinity parameters for the centre were not calculated because the equation represents an hyperbola. c, represents a constant; cz-c6 are regression coefficients that can be used to generate the response equations according to the expression y = c, + ca(t) + c&2) + c&T) + c&F) + c&t l S).
31
29
2
25
:
Zoeal stage
id. (“C)
Results ofthe multiple regression analysis for each zoeal stage of&f. rosenbergilarvae from eggs incubated at three temperatures during embryouic development. Centre S and 1 values represent the salinity and temperature conditions for maximum response.
44
G. GOMEZ
DIAZ
zoeae have wider salinity and temperature tolerances, and as development advances, the Iarvae become limited to narrower ranges of temperature and salinity in which maximum survival is possible. These changes in capacity with the ontogeny of the larvae are also indicated by the variation ofthe centers of response surfaces in Table II. Among
2
3
4
5
ZOEAL
6
7
8
9
1011PL
STAGE
Fig. 3. Variation in the area of response surfaces estimated as 30% attainment to each larval stage of M. beak. Egg incubation tem~ratur~s: 25 “C (white circles); 29°C (black circles); 31 “C (white squares).
the three groups, larvae from eggs incubated at 25 “C appear to be more tolerant to the combined effect of temperature and salinity; these larvae are clearly shown to be more resistant to lower temperatures and a wider range of salinities. The duration of the larval development to metamorphosis is also influenced by the rearing temperature of the zoeae (Table I). The median number of days required to metamorphosis of the larvae from eggs incubated at 25 or 3 1 oC was in general smaller than that of the larvae from eggs incubated at 29 “C. In the case of the larvae reared at low temperature (22 “C) the larval duration extended markedly (Table I). DISCUSSION
Survival and growth of h4. rosenbergii larvae are limited to various temperature and salinity conditions, with temperature playing the more important r61e. Considering the results from the present experiment, the possibility to obtain high metamorphosis rates over a wider range of temperature and salinity conditions is increased when animals are maintained at a 25 “C incubation temperature during embryonic development. Thus, it is apparent that the response of M. rtxenbergii larvae can be modified by the incubation temperature during the embryonic development (Figs. l-2). By comparison
EFFECI’ OF EMBRYONIC
TEMPERATURE
ON MACROBRACHIlLU
DEVELOPMENT
45
of the areas of the response surfaces as a measure of response capacity (Alder-dice, 1972), the variations in the optimum response can be evaluated. For example, in Fig. 3, it can be noted that for larvae from eggs incubated at 29 and 31 “C the pattern of variation among the larval stages is somewhat similar. The shift to relatively wider salinity and temperature ranges (larger response surface areas) in the larvae from eggs incubated at 25 “C is an indicator of an increased larval tolerance to both higher and lower salinities (Fig. 3). A number of authors have reported different temperature and salinity ranges as optimum conditions for the rearing of A4. rosenbergii larvae (Ogasawara, 1976; Uno & Yagi, 1980; New 8z Singholka, 1982). One could speculate and attribute all these differences in optimum conditions to genotypic variability, state of acclimation of the prawns in question, or to variations caused by differences in experimental methodology. The striking difference in the response (tolerance) of the larvae from eggs incubated at 25 “C is attributable to acclimation of the larvae to low temperatures during the embryonic development. Richard (1978) found comparable results studying the tolerance to extreme temperatures in Palaemon serratus of different sizes, and concluded that acclimation has a pronounced effect on tolerance. Acclimation at low temperatures increased survival at extreme low temperatures, and acclimation to high temperature increased survival at high temperatures. Also Silver-thorn & Reese (1978) reported improved survival of M. rosenbergii postlarvae acclimated to < 22 ‘C. Although embryonic (Nakamura & Baba, 1982) and larval development duration (Dawirs, 1985) of crustaceans change according to the rearing conditions, the dilferences in response of the larvae from the present experiment can be envisioned as quantitative aspects of performance (tolerance to the combined effect of temperature and salinity) that have been modified by nongenetic adaptation (Kinne, 1962, 1964) of the larvae to the incubation temperature during embryonic development. Variations in the adaptation of crustaceans can be assessed quantitatively by measuring differences in tolerance or performance of individuals with different environmental histories. Preston (1985) concluded that temperature and salinity conditions for maximum hatching success in Metapenaeus bennettae depend on the conditions during spawning, and that the conditions for maximum survival and growth depended on the rearing conditions prior to experimentation. Similarly, other laboratory studies have shown that the effect of temperature and salinity may vary according to previous environmental history (Preston, 1985). The different results for the larvae from eggs incubated at 25, 29, or 3 1 “C can be interpreted as variations in resistance adaptation (tolerance to extreme conditions) acquired or modified during embryonic development. Theoretically, these differences may have been determined at least in part by other factors, like the conditions at which the parent stock developed gonads, its nutritional state or even by factors of genetic origin. In the present experiment, by using parents from the same stock, and the sperm from one male, it is likely that the influence of genetic adaptation was minimized. Nevertheless, any one or several of these other factors could explain that the larvae incubated at 29 ‘C have a more restricted tolerance range of temperature and salinity conditions than those incubated at 25 and 31 “C; one could consider the
46
G. GOMEZ DIAZ
physioIo~c~ state of the berried female acclimated to 29 oC as being responsibIe at least in part for the different capacity of response. The existence of developmental (ontogenic) related changes in the response of crustacean larvae has been suggested by a number of authors (Jones, 198 1; Moreira et al., 1982, 1983). In agreement, variations in resistance adaptation at the different stages of larval development were found in the zoeae from the three incubation temperatures (Fig. 3, Table II). At least for the zoeal stages and the postlarva, tolerance decreases with age. It may be advantageous, therefore, to have knowledge of the state of acclimation (environmental history) of the parental stock and the larvae, to assess properly the performance of ~dividu~s exposed to different salinity and temperature conditions during the seedling production process of M. ~ose~r~j hatcheries.
ACKNOWLEDGMENTS
The present study was supported in part by a grant from the Japanese Ministry of Education. The author is grateful to Prof. A. Ohno from the Fisheries Resources Research Laboratory, Tokyo University of Fisheries, for assistance with response surface analysis, and to Dr. Y. Ogasawara for his interest.
REFERENCES
ALDERDICE,D. F., 1972.Environmental factors. In, Marine ecology, edited by 0. Kinne, Wiley-Interscience, New York, pp. 1659-1772. BLASZKOWSKI,C. & G. MOREIRA,1986. Combined effects of temperature and salinity on the survival and duration of the larval stages of Pagu~~ criniricornb (Dana) (Crustacea, Pagmidae). J. Exp. Mar. Biol. Eeol.. Vol. 103, pp. 77-86. Box, G. E. P., 1954.The exploration and exploitation of response surfaces: some general considerations and examples. Biometrics, Vol. IO; pp. 16-60. Box, G.E. P., 1956. The determination of optimum conditions. In, Design and analysti of industtial experiments, edited by O.L. Davis, Olivei & Boyd, London. pp. 495-578. Box, G. E. P. & P. V. YOULE, 1955. The exploration and exploitation of response surfaces: an example of the link between the fitted surface and the basic mechanism of the system. Biomeh-tcs, Vol. II, pp. 287-323. CHOU~H~RY,P. C., 1970. Responses of larval Ma~robra~hium carcinus (L.) to variations in salinity and diet (Decapoda, Palaemonidae). C~fuceu~ff (l&den), Vol. 20, pp. 113-120. CHOUDHURY,P.C., 1971. Laboratory rearing of the palaemonid shrimp ~a~robru~~um acunthurus (Wiegmann, 1836). Cr~~taceana (L&den), Vol. 21, pp. 113-125. DAWIRS, R.R., 1985. Temperature and larvai development of Carcinus maenas (Decapoda) in the laboratory; predictions of larval dynamics in the sea. Mar. Ecal. Prog. Ser., Vol. 24, pp. 297-302. GOMEZ DIAL G. & A. OHNO, 1986.Possible significance of rearing conditions of ovigerous Mucrobrachium rosenbergii (de Man). In, The First Asian Fisheries Forum, edited by J. L. Maclean et al., Asian Fisheries Society, Manila, Philippines, pp. 45-48. GOMEZ DIAZ, G., 1987. Influence of the parental stock on the larval development of Macrobruchtum rosenbergii. Int. J. Invertebr. &prod. Dev., Vol. 12, pp. 45-56. HOLXCHMI~‘,K.H. & E. PFEILER, 1984.Effect of salinity on survival and development of larvae and postlarvae ofhkrobruchium americanurn Bate (Decapoda. Palaemonidae), Crustaceana (Leiden), Vol. 46, pp. 23-28.
EFFECI’ OF EMBRYONIC
TEMPERATURE
ON MACROBRACHZUM
DEVELOPMENT
47
IOARASHI,Y., H. YAGI& Y. UNO, 1984. Influence combi& des facteurs temp6rature et &nit& sur la croissance larvaire de Palaemon pac@us (S~pson) (P~aemo~des, Decapodes, Crustacbs), Mer (Tokyo), Vol. 22, pp. 287-292. JONES,M. B., 1981. Effect oftemperature, season, and stage oflife cycle on salinity tolerance ofthe estuarine crab Helice crassa Dana (Grapsidae). J. Exp. Mar. Biol. Ecol., Vol. 52, pp. 271-282. KINNE, O., 1962. Irreversible non-genetic adaptation. Comp. Biochem. Physiol., Vol. 5, pp. 265-282. KINNE, O., 1964. Non-genetic adaptation to temperature and salinity. Helgol. Weiss.Meeresunters., Vol. 9, pp. 433-458. KNOWLTON,R. E., 1974. Larval developmental processes and controllii factors in decapod crustacea, with emphasis on caridea. 7?zaIassiaJugosi., Vol. 10, pp. 138-158. MOREIRA,G. S., J. C. MCNAMARA& P. S. MOREIRA,1979.The combined effects of temperature and salinity on the survival and moulting of early zoeae of Macrobrachi~ kol~~ (Decapoda : P~aemo~dae). Biol. Fisiol. Anim. Univ. Sdo Paula, Vol. 3, pp. 81-93. MOREIRA,G. S., J. C. MCNAMARA& P. S. MOREIRA, 1982. The effect of salinity on the metabolic rates of some palaemonid shrimp larvae. Aquacuiture, Vol. 29, pp. 95-100. MOREIRA, G.S., J.C. MCNAMARA, S.E. SHUMWAY8c P.S. MOREIRA, 1983. Osmoregulation and respiratory metabolism in Brazilian Macrobrachium (Decapoda, Palaemonidae). Comp. Biockem. PhysioL, Vol. 74A(l), pp. 57-62. NAKAMURA,K. & K. BABA, 1982. Observations on the development of the post-embryo of the shrimp, Palaemon paucidens. &fern. Fat. Fisk. Kagoshima Univ., Vol. 31, pp. 125-139. NEW, M. B. & S. SINGHOLKA,1982. Freshwater prawn farming. A manual for the culture OfMaffobrac~~ rosenberg%. FAO Fisk. Tech. Pap., No. 225, 116 pp. OGASAWARA,Y., 1976. Tansui ebi toku ni tenagaebi to sono yooshoku. In, Tansui zooshoku, edited by D. Inaba, pp. 457-475. (In Japanese.) OGASAWARA,Y., S. KOSHIO& Y. TAKI, 1979. Responses to salinity in larvae from three local populations of the freshwater shrimp, Macrobrackium nipponense. Bull. Jpn. Sot. Sci. F&k., Vol. 45, pp. 937-943. PRESTON,N., 1985. The combined effects of temperature and salinity on hatching success and the survival, growth, and development of the larval stages ofMetapenaeus bennettae (Racek & Dall). J. Eq. Mar. Biol. Ecol., Vol. 85, pp. 57-74. RICHARD,P., 1978. TolCrance aux tempkatures extrkmes de PaIaemon serratus (Pennant): influence de la taille et de Pacclimatation. J. Exp. Mar. Biol. Ecol., Vol. 35, pp. 137-146. ROCHANABURANON, ‘I’. & D.I. WILLIAMSON,1976. Laboratory survival of larvae of Palaemon elegant Rathke and other carideau shrimps in relation to their distribution and ecology. Esruarine Coastai Mar. Sci., Vol. 4, pp. 83-91. SILVERTHORN,S.U. & A.M. REESE, 1978. Cold tolerance at three salinities in postlarval prawns, Macrobrackium rosenbergi? (de Man). Aquaculture, Vol. 15, pp. 249-255. UNO, Y. & H. YAGI, 1980. Influence de la combinaison des facteurs temperature et salinitt sur la croissance larvaire de Macrobrackium rosenbet@ (de Man) (Palaemonides, DCcapodes, Crustacts). Mer {Tokyo), Vol. 18, pp. 171-178. YAGI, H. & H. CECCALDI,1983. Croissance, survie et respiration des stades larvaires de Pa~aemon serratus (Pennant), Crustacea Decapoda, &diffbrentes combinaisons de salinitt et de tempcature. Rapp. Comm. fnt. Mer MPditerr., Vol. 28, pp. 345-348. YAGI,Y. & H. CECCALDI,1984. Influence combinCe des facteurs temptrature et salinitC sur la mttamorphose et la croissance larvaire de la crkvette rose Palaemon serratus (Pennant) (Crustacea, Decapoda, Palaemonidae). Aquaculture, Vol. 37, pp. 73-85. YAGI,H. & Y. UNO, 1981. Influence de la combinaison des facteurs temptrature et salinitt sur la croissance larvaire de Macrobrackium nipponense (De Haan) (Palaemonides, Dbcapodes, Crusta&). Mer (Tokyo), Vol. 19, pp. 93-99.
39
Elsevier
JEM 00982
Effect of environmental embryonic temperature on larval development of Macrobrachium rosenbergii (De Man) Gabriel
Gomez
Diaz
Aquaculture Depaninent, Faculty of Applied Biological Sciences, Hiroshima Universiry. Fukuyama,‘Japan
(Received 3 March 1987; revision received 29 July 1987; accepted 3 September 1987) Berried females of Macrobrachium rosenbergii (De Man) from Anuenue stock were allowed to incubate their eggs at three different temperatures (25,29, and 31 “C). The newborn larvae were reared in the laboratory from hatch through completion of the metamorphosis to postlarva in 30 combinations of temperature (22-34 “C) and salinity (O-34 ppt). Survival and stage attainment rates were observed. Multiple linear regression analysis and response surface methodology were used to estimate the response of larvae to these different temperature and saliity combinations. Dissimilarities in the response of zoeae from the three egg incubation temperatures were found. Larvae from eggs incubated at 25 “C during embryonic development showed tolerance to a broader range of temperature and salinity conditions than those incubated at 29 or 31 “C. The response also changed with the ontogeny of the larvae. The zoeae are considered to have undergone acclimation during embryonic development, thus eliciting a different response. Abstract:
Key words: Environmental history; Larval development; Macrobrachium rosenbergi% Palaemonid prawn; Salinity; Temperature
INTRODUCTION
Temperature and salinity are two of the most important environmental factors in marine and brackish water habitats affecting the life processes of crustacean larvae, especially the rates of survival and growth. The combined effects of these two factors have been studied to assess the optimum rearing conditions of a number of decapod larvae (Choudhury, 1970, 1971; Knowlton, 1974; Rochanaburanon & Williamson, 1976; Moreira et al., 1979; Ogasawara et al., 1979; Uno & Yagi, 1980; Yagi 8z Uno, 1981; Yagi 8c CeccaIdi, 1983, 1984; Holtschmit & Pfeiler, 1984; Igarashi et al., 1984; Blaszkowski & Moreira, 1986). To date, there is no information on the combined effect of these environmental factors on development of Mucrobrachium larvae. This paper deals with the evaluation of combined temperature and salinity effects on the zoeal stages of Macrobrachium rosenbergii (De Man) after their incubation at ditTerent temperatures.
Correspondence address: G. Gomez Diaz, Aquaculture Department, Faculty of Applied Biological Sciences, Hiroshima University, 2-17 Midorimachi, Fukuyama 720, Japan. 0022-0981/87/$03.50 0 1987 Elsevier Science Publishers B.V. (Biomedical Division)
40
G.GOMEZ METHODS
AND
DIAZ
MATERIALS
Anuenue broodstock was used for the present experiment. The rearing and feeding of prawns were the same as reported previously (Gomez Diaz & Ohno, 1986). Three females were inseminated by the same male to minimize variations of genetic origin; after mating, each berried female. was allowed to acclimatize to one of the three egg incubation temperatures (25, 29, or 31 “C), by changing the water temperature at the rate of 1 “C every 2 h. Within 1 h after hatching, the zoeae were transferred to l-l beakers and allowed to acclimatize to one of the six experimental salinities (0,6.8, 13.6, 20.4,27.2, and 34 ppt), changing the salinity at a rate of 6.8 ppt per 30 min with the egg incubation temperature unchanged. After salinity acclimation, dupfcate samples of 40 individuals were put into 500-cc culture dishes and these were placed in constant temperature water baths. Then the larvae were allowed to acclimatize to the five experimental temperatures (22,25,28, 31, and 34 “C) by changing the temperature at a rate of 3 ‘C every 2 h. Survival and development stage were recorded on a daily basis; development was calculated as the median number of days required to reach each larval stage, and response surface methodology (Box, 1954, 1956; Box & Youle, 1955; Alderdice, 1972) was used to produce response surface equations from these data. The functional form used was a full quadratic with temperature and salinity as interaction terms. These response surface equations were further expressed in accordance with the formula of a common ellipse (Gomez Diaz, 1987), and from this, the surface area was determined. RESULTS
Differences were found among Anuenue stock zoeae from eggs incubated at the three temperatures. The duration from spawning to hatch was 26, 17, and 16 days for the temperatures of 25,29, and 3 1 ’ C, respectively. According to the survival data (Table I), the larvae from eggs incubated at 29 “C metamorphosed from 25 to 34 ‘C, and a metamorphosis rate higher than 30% was obttied in the range of 28-31 “C and 6.8-27.2 ppt of salinity. In the case of egg incubation at 31 “C, the temperature range to obtain postlarvae was 25-3 1 “C, and metamorphosis rates of > 40% were obtained only at 25 “C and 20.4 ppt, 28 “C and the salinity range of 13.6-27.2 ppt, and 31 “C and 13.6 ppt. However, in the case of egg incubation at 25 “C, the temperature range where the larvae could metamorphose, was shifted to 22-3 1 ‘C, while > 70% metamorphosis was observed in the range of 25-3 1 ‘C and at salinities of 6-8-34 ppt (13.6 and 20.4 ppt only, for the case of 25 “C) (Table I). By means of the response surface analysis, these differences become more obvious. In Fig. 1, the response contours were plotted for 60% attainment to the ninth zoea. This model displays the larval tolerance to wider ranges of salinity in every instance compared to the ranges of tolerance to temperature. The differences in tolerance among the three groups are significant specially in the case of larvae from eggs incubated at
EFFECT OF EMBRYONIC
TEMPERATURE
41
ON MACROBRACHZUM DEVELOPMENT
29 “C where the zoeae are restricted to a limited range of temperature and salinity conditions. This can also be noted in Fig. 2, where the response surfaces are plotted as 30% metamorphosis to postlarva for larvae of each of the three egg incubation temperatures. The larvae from eggs incubated at 3 1 and 25 “C during embryonic development display more tolerance to lower temperatures and more resistance to combined conditions of temperature and salinity than the larvae from eggs incubated at 29 ’ C. This means that larvae incubated at 29 oC have more narrow tolerance limits in respect to temperature and salinity conditions than those of the other two groups.
TABLE I Survival and median number of days to metamorphosis of M. rosenbergii larvae incubated at three temperatures during embryonic development and reared under 30 combinations of temperature-salinity. s (PPt)
22
25
28
31
34
0.0 6.8 13.6 20.4 27.2 34.0 0.0 6.8 13.6 20.4 21.2 34.0 0.0 6.8 13.6 20.4 27.2 34.0 0.0 6.8 13.6 20.4 21.2 34.0 0.0 6.8 13.6 20.4 27.2 34.0
Metamorphosed larva (%)
Median number of days to metamorphosis
Incubation temperature (“C)
Incubation temperature to C)
25
29
31
0.0 0.0 1.5 17.5 18.8 0.0 0.0 41.3 70.0 70.0 53.8 28.8 0.0 66.3 18.8 88.8 81.3 72.5 0.0 51.3 12.5 80.0 76.3 76.3 0.0 0.0 0.0 0.0 0.0 0.0
0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 3.8 1.5 1.5 0.0 45.0 53.8 42.5 46.3 16.3 0.0 30.0 41.3 11.3 35.0 18.8 0.0 0.0 1.3 0.0 0.0 0.0
0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 3.8 43.8 18.8 5.0 0.0 28.8 43.8 57.5 60.0 20.0 0.0 28.8 52.5 37.5 35.0 20.0 0.0 0.0 0.0 0.0 0.0 0.0
25
29
61.0 61.7 52.1 77.0
-
39.8 33.1 31.0 31.5 39.2
49.7 40.0 43.0 52.0
61.5 46.5 39.1 41.5 56.5
25.4 23.1 23.1 23.2 75.8
42.0 32.4 37.4 37.8 41.0
35.8 30.2 34.4 35.3 42.0
21.0 18.1 19.1 19.3 21.1
34.0 28.8 21.0 26.8 34.0
28.9 27.0 29.3 34.5 36.7
27.5
31
G. GOMEZ DIAZ
42
The reduced length of the temperature axes, as seen in Figs. 1-2, indicates that M. rosenbergii zoeae are more restricted by temperature than by salinity conditions. It was found that the response surfaces obtained are ellipsoid in shape for most of the cases (hyperbolae were obtained for the second zoea from eggs incubated at 29 “C)
0
6.6
13.6 SALINITY
20.4
27.2
34
ppt
Fig. 1. Response surfaces estimated as 60% attainment to the ninth zoed stage ofM. rosenbergiilarvae. The numbers in the response contours indicate the egg incubation temperature (“C).
O
6.8
13.6 SALINITY
20.4
27.2
34
ppt
Fig. 2. Estimated response surfaces for 30?,, metamorphosis to postlarva of M. rosenbergii larvae. The number in the response contours indicates the egg incubation temperature (“C).
(Table II). On this basis, a comparison between the response contours for the different larval stages was accomplished by means of the area of ellipsoids (estimated as 30% attainment to each stage) plotted in Fig. 3 against zoeal stage. The first four larval stages have bigger area values that decrease as development progresses. This means that early
TABLE
II
10 11 Pl
i
PI 2 3 4 5 6
:‘:
: 9 10 11 Pl 2 3 4 5 6 I
;
4.1579 22.8368 31.4726 69.4083 84.3401 95.6747 100.5820 101.8910 102.1320 100,755o 96.3106 - 0.1949 27.6589 69.1446 91.6316 93.6479 89.7959 84.3115 81.1767 55.1196 42.8657 42.1145 16.8827 76.2356 75.0758 91.5632 119.1850 118.7180 110.1630 101.5750 67.2888 5 1.6230 49.8659
- 0.07761 - 0.38520 - 0.53403 - 1.23332 - 1.50782 - 1.71941 - 1.80871 - 1.83017 - 1.83185 - 1.80379 - 1.72602 - 0.00003 - 0.47287 - 1.20696 - 1.61865 - 1.65831 - 1.59218 - 1.49293 - 1.43511 - 0.97214 - 0.75392 - 0.74068 - 0.31413 - 1.30613 - 1.29459 - 1.60209 -2.11461 - 2.10627 - 1.95089 - 1.79553 - 1.18541 - 0.9093 1 - 0.87956
=2 8.34234 8.57251 8.31450 7.15482 7.34820 7.53192 7.86694 7.90102 6.60569 5.16047 4.20689 8.47097 7.34206 3.36152 3.05463 3.23193 2.72318 2.77234 2.94017 1.84809 1.69261 1.66692 6.14776 2.96613 2.21957 3.40451 5.23248 5.50833 5.30665 5.16861 3.59545 2.99021 2.88269
c3
CS
0.03626 0.03735 0.03844 0.01880 - 0.01005 - 0.02519 - 0.04394 - 0.51704 - 0.02735 0.00673 0.02351 0.02201 0.07253 0.13135 0.52544 0.0060 1 0.00492 - 0.00121 - 0.09788 0.00508 0.0029 1 0.00183 0.12375 0.50118 0.17158 0.11748 0.2298 1 -0.01111 - 0.01833 - 0.02339 - 0.01240 - 0.00465 - 0.00249
- 0.22342 - 0.23489 - 0.22977 - 0.18089 -0.16715 - 0.16346 - 0.16079 - 0.15742 - 0.14358 - 0.13333 - 0.11765 - 0.21286 - 0.22762 - 0.16685 - 0.10638 - 0.07942 - 0.06292 - 0.06098 - 0.06128 - 0.04939 - 0.04786 - 0.04642 - 0.23705 - 0.16613 - 0.16439 - 0.15762 - 0.14163 - 0.12001 - 0.10843 - 0.10238 - 0.0790 1 - 0.07501 - 0.07389
-
C4
Regression coefficients
Multiple correlation coefficient 0.900265 0.911298 0.906859 0.883407 0.878588 0.887055 0.886063 0.886447 0.892390 0.896824 0.905450 0.881828 0.901684 0.890123 0.849078 0.839871 0.836378 0.838834 0.838262 0.774702 0.730060 0.726832 0.877406 0.881488 0.894046 0.902584 0.891338 0.870033 0.858831 0.858310 0.836601 0.809033 0.809604
C6
- 38.029 - 319.534 - 442.854 - 945.659 - 1145.150 - 1294.440 - 1360.390 - 1379.660 - 1384.580 - 1370.070 - 1310.650 22.954 - 384.556 - 957.139 - 1257.970 - 1284.150 - 1231.230 - 1157.940 - 1117.220 - 760.605 - 593.428 - 582.993 - 205.48 - 1073.25 - 1051.39 - 1269.45 - 1635.74 - 1632.91 - 1519.05 - 1404.05 - 933.93 - 717.54 - 692.58
31.0 30.5 30.5 29.4 28.3 28.1 28.1 28.1 28.3 28.3 28.3 _* 30.9 29.8 28.7 28.3 28.2 28.2 28.2 28.4 28.5 28.5 31.8 30.7 30.2 28.3 27.9 27.1 27.6 27.6 27.7 28.0 28.0
21.0 22.7 22.9 21.8 20.8 21.7 22.0 22.0 20.5 19.0 19.0 2T.o 21.8 21.4 21.4 22.7 22.5 22.2 20.2 18.6 18.5 21.3 20.7 20.6 21.3 21.1 20.9 20.7 20.6 20.4 20.0 20.7
f (“Q
s (PPt)
Centre
Lt., egg incubation temperature; pi, postlarva; *temperature and salinity parameters for the centre were not calculated because the equation represents an hyperbola. c, represents a constant; cz-c6 are regression coefficients that can be used to generate the response equations according to the expression y = c, + ca(t) + c&2) + c&T) + c&F) + c&t l S).
31
29
2
25
:
Zoeal stage
id. (“C)
Results ofthe multiple regression analysis for each zoeal stage of&f. rosenbergilarvae from eggs incubated at three temperatures during embryouic development. Centre S and 1 values represent the salinity and temperature conditions for maximum response.
44
G. GOMEZ
DIAZ
zoeae have wider salinity and temperature tolerances, and as development advances, the Iarvae become limited to narrower ranges of temperature and salinity in which maximum survival is possible. These changes in capacity with the ontogeny of the larvae are also indicated by the variation ofthe centers of response surfaces in Table II. Among
2
3
4
5
ZOEAL
6
7
8
9
1011PL
STAGE
Fig. 3. Variation in the area of response surfaces estimated as 30% attainment to each larval stage of M. beak. Egg incubation tem~ratur~s: 25 “C (white circles); 29°C (black circles); 31 “C (white squares).
the three groups, larvae from eggs incubated at 25 “C appear to be more tolerant to the combined effect of temperature and salinity; these larvae are clearly shown to be more resistant to lower temperatures and a wider range of salinities. The duration of the larval development to metamorphosis is also influenced by the rearing temperature of the zoeae (Table I). The median number of days required to metamorphosis of the larvae from eggs incubated at 25 or 3 1 oC was in general smaller than that of the larvae from eggs incubated at 29 “C. In the case of the larvae reared at low temperature (22 “C) the larval duration extended markedly (Table I). DISCUSSION
Survival and growth of h4. rosenbergii larvae are limited to various temperature and salinity conditions, with temperature playing the more important r61e. Considering the results from the present experiment, the possibility to obtain high metamorphosis rates over a wider range of temperature and salinity conditions is increased when animals are maintained at a 25 “C incubation temperature during embryonic development. Thus, it is apparent that the response of M. rtxenbergii larvae can be modified by the incubation temperature during the embryonic development (Figs. l-2). By comparison
EFFECI’ OF EMBRYONIC
TEMPERATURE
ON MACROBRACHIlLU
DEVELOPMENT
45
of the areas of the response surfaces as a measure of response capacity (Alder-dice, 1972), the variations in the optimum response can be evaluated. For example, in Fig. 3, it can be noted that for larvae from eggs incubated at 29 and 31 “C the pattern of variation among the larval stages is somewhat similar. The shift to relatively wider salinity and temperature ranges (larger response surface areas) in the larvae from eggs incubated at 25 “C is an indicator of an increased larval tolerance to both higher and lower salinities (Fig. 3). A number of authors have reported different temperature and salinity ranges as optimum conditions for the rearing of A4. rosenbergii larvae (Ogasawara, 1976; Uno & Yagi, 1980; New 8z Singholka, 1982). One could speculate and attribute all these differences in optimum conditions to genotypic variability, state of acclimation of the prawns in question, or to variations caused by differences in experimental methodology. The striking difference in the response (tolerance) of the larvae from eggs incubated at 25 “C is attributable to acclimation of the larvae to low temperatures during the embryonic development. Richard (1978) found comparable results studying the tolerance to extreme temperatures in Palaemon serratus of different sizes, and concluded that acclimation has a pronounced effect on tolerance. Acclimation at low temperatures increased survival at extreme low temperatures, and acclimation to high temperature increased survival at high temperatures. Also Silver-thorn & Reese (1978) reported improved survival of M. rosenbergii postlarvae acclimated to < 22 ‘C. Although embryonic (Nakamura & Baba, 1982) and larval development duration (Dawirs, 1985) of crustaceans change according to the rearing conditions, the dilferences in response of the larvae from the present experiment can be envisioned as quantitative aspects of performance (tolerance to the combined effect of temperature and salinity) that have been modified by nongenetic adaptation (Kinne, 1962, 1964) of the larvae to the incubation temperature during embryonic development. Variations in the adaptation of crustaceans can be assessed quantitatively by measuring differences in tolerance or performance of individuals with different environmental histories. Preston (1985) concluded that temperature and salinity conditions for maximum hatching success in Metapenaeus bennettae depend on the conditions during spawning, and that the conditions for maximum survival and growth depended on the rearing conditions prior to experimentation. Similarly, other laboratory studies have shown that the effect of temperature and salinity may vary according to previous environmental history (Preston, 1985). The different results for the larvae from eggs incubated at 25, 29, or 3 1 “C can be interpreted as variations in resistance adaptation (tolerance to extreme conditions) acquired or modified during embryonic development. Theoretically, these differences may have been determined at least in part by other factors, like the conditions at which the parent stock developed gonads, its nutritional state or even by factors of genetic origin. In the present experiment, by using parents from the same stock, and the sperm from one male, it is likely that the influence of genetic adaptation was minimized. Nevertheless, any one or several of these other factors could explain that the larvae incubated at 29 ‘C have a more restricted tolerance range of temperature and salinity conditions than those incubated at 25 and 31 “C; one could consider the
46
G. GOMEZ DIAZ
physioIo~c~ state of the berried female acclimated to 29 oC as being responsibIe at least in part for the different capacity of response. The existence of developmental (ontogenic) related changes in the response of crustacean larvae has been suggested by a number of authors (Jones, 198 1; Moreira et al., 1982, 1983). In agreement, variations in resistance adaptation at the different stages of larval development were found in the zoeae from the three incubation temperatures (Fig. 3, Table II). At least for the zoeal stages and the postlarva, tolerance decreases with age. It may be advantageous, therefore, to have knowledge of the state of acclimation (environmental history) of the parental stock and the larvae, to assess properly the performance of ~dividu~s exposed to different salinity and temperature conditions during the seedling production process of M. ~ose~r~j hatcheries.
ACKNOWLEDGMENTS
The present study was supported in part by a grant from the Japanese Ministry of Education. The author is grateful to Prof. A. Ohno from the Fisheries Resources Research Laboratory, Tokyo University of Fisheries, for assistance with response surface analysis, and to Dr. Y. Ogasawara for his interest.
REFERENCES
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TEMPERATURE
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