Growth and lipid composition of phyllosomata of the southern rock lobster, Jasus edwardsii, fed enriched Artemia

Newly hatched phyllosoma larvae of Jasus edwardsii were on‐grown to stage V. Using triacylglycerol‐rich marine oil nutrient sources and microalgae, Artemia were enriched with the major polyunsaturated fatty acids (PUFA) to ratios similar to that of wild‐caught phyllosomata. Artemia enriched by different methods were fed to cultured phyllosomata. At each stage animals were counted, measured and sampled for lipid analyses. Survival was highest from stages II to III (62–86%), with mean total survival at 3–12%. From stages I to V larvae increased in mass (0.2–2.2 mg) and total length (2.1–5.8 mm), and decreased in total lipid. The major lipid class in all phyllosomata was polar lipid, followed by sterol, with no triacylglycerol detected. The main fatty acids were 18:1(n‐9)c, 18:2(n‐6), 16:0, 18:0, eicosapentaenoic acid [EPA; 20:5(n‐3)], 18:1(n‐7)c, arachidonic acid [AA; 20:4(n‐6)] and docosahexaenoic acid [DHA; 22:6(n‐3)]. On‐grown phyllosomata had levels of AA and EPA similar to that of wild phyllosomata, but contained markedly lower levels of DHA. Strategies for enhancement of DHA levels will be needed for culture of rock lobster phyllosomata.     

Lipid and fatty acid composition of likely zooplankton prey of spiny lobster (Jasus edwardsii) phyllosomas

Several of the world's major spiny lobster fisheries, including Jasus edwardsii in Australasia, have gone into dramatic decline due to decreasing recruitment of their lecithotrophic postlarvae. There is evidence that the decline is related to poor nutritional condition of the postlarvae, especially lipid that is accumulated in large quantities during the preceding pelagic larval stage. Therefore, characterizing the lipid composition of the likely potential zooplankton prey of the larvae (phyllosomas) of spiny lobsters will provide new insights into their nutritional requirements. The lipid class and fatty acid composition of more than 30 species of likely zooplankton prey of the larvae of the spiny lobster, J. edwardsii, were determined. These results showed that most zooplankton prey had a high proportion of their lipid content as polar lipid (PL) (range of 9.4–94.8%, mean of 76.1 ± 2.6%). Zooplankton prey provide phyllosomas with polyunsaturated fatty acids (PUFA) for growth and development, as well as a range of other important fatty acids that are accumulated as PL and used for fuelling the migration of the subsequent lecithotrophic postlarvae across the continental shelf. Overall, these results indicate that phyllosomas consume prey with wide ranging lipid content, but dominated by PL, and high in docosahexaenoic acid, eicosapentaenoic acid and the key fatty acids used for energy storage.     

Effects of marine reserve protection on spiny lobster (Jasus edwardsii) abundance and size at Tonga Island Marine Reserve,New Zealand

• 1. Diving surveys were undertaken to investigate the effects of marine reserve protection on spiny lobster (Jasus edwardsii) populations at Tonga Island Marine Reserve, northern South Island, New Zealand over a 2 year period from December 1998 to December 2000.
• 2. Spiny lobsters were 2.8 times more abundant overall, and mean size was 19 mm carapace length larger in shallow transects and 28 mm carapace length larger in deep transects, in the marine reserve than at adjacent fished sites. That pattern was evident despite very high variability within sites, and among sites within reserve and fished areas.
• 3. Large reproductive males were 10 times more abundant within the reserve compared to adjacent fished areas, suggesting that more eggs would be fertilized in the reserve than on the adjacent fished coast.
• 4. Estimates of size‐specific fecundity, combined with abundances of females, suggested that almost nine times more eggs would be produced in the reserve than in fished areas.
• 6. We estimate that the mean abundance of spiny lobster in the reserve has increased by 22%, 5 years after its establishment, indicating an annual population increase of 4.4%. Over the same period, abundance of spiny lobster outside the reserve has declined by 2.9% per annum.
• 7. Based on known spiny lobster movements, we suggest that marine reserves of more than 10 km length should be given priority over smaller reserves. Smaller reserves will, however, protect part of the population for at least a portion of their lifespan.
• 8. Previous studies of movement of J. edwardsii suggest that spillover from the reserve should occur, and as population density increases we predict that more spiny lobsters will move out from the reserve.

Copyright © 2002 John Wiley & Sons, Ltd.     

Tissue content, fecundity and quality of eggs and phyllosoma larvae after supplementing the diet of spiny lobster Jasus edwardsii broodstock with ascorbic acid-enriched Artemia biomass

Ascorbic acid (AA)‐enriched Artemia in alginate pellets and unenriched pellets were fed to Jasus edwardsii broodstock to supplement AA intake of the basal diet (mussels, squid and compound prawn pellets) during ovarian development before egg extrusion. Pellet AA content ranged from 150 μg g^?1 (unenriched) to 9153 μg g^?1 (enriched). The basal diet (150 μg AA g^?1) was compared with low (150 μg AA g^?1), medium (450 μg AA g^?1) and high (1350 μg AA g^?1) AA supplementation. Dietary AA content was obtained using combinations of unenriched and AA‐enriched Artemia in combination with the basal diet. Supplementation resulted in ovarian AA saturation at ～240 μg g^?1, a significant increase over 152 μg g^?1 at time 0. Digestive gland concentrations were 76–92 μg AA g^?1 for diets containing ≤450 μg AA g^?1, but reached 270 μg AA g^?1 for the high supplement. The considerable AA store in tail muscle appeared to be translocated to the ovary during maturation. There was no significant AA depletion in eggs during embryogenesis suggesting minimal AA utilization during this phase. Jasus edwardsii spawns once annually, unlike other multiple spawning crustaceans. Therefore, AA supplementation did not alter fecundity or phyllosoma quality, but resulted in a dose‐dependent increase (up to 33%) in AA content of eggs and phyllosoma.     

Feeding juvenile Artemia enriched with ascorbic acid improves larval survival in the spiny lobster Jasus edwardsii

Newly hatched Jasus edwardsii phyllosoma were fed unenriched Artemia [endogenous ascorbic acid (AA) concentration of 166 μg g^?1 dry weight (dw)], Artemia supplemented with algae (AA concentration 594 μg g^?1 dw) or with ascorbyl‐2‐polyphosphate (A2P) (AA concentration 11 737 μg g^?1 dw) to examine possible benefits of AA enhancement on culture. Plain or algal‐enriched Artemia were fed continuously for 28 days in two treatments during the study. Four other treatments received A2P‐enriched Artemia on a progressive basis starting from the commencement of the trial (D‐0), the third (D‐3), sixth (D‐6) or ninth day (D‐9) of Stage I (14 days) and similarly during Stage II (14 days). Prior to the commencement of A2P supplementation, plain Artemia were supplied to these animals. By Stage III (28 days feeding), algal, D‐0 and D‐3 phyllosoma had attained the largest size. The uptake and retention of AA by Stage III phyllosoma appeared to be dose‐dependent with the highest concentration of AA incorporation evident in D‐0 phyllosoma (1816 μg g^?1 dw), while algal and plain phyllosoma contained the lowest concentrations (600 and 300 μg g^?1 dw, respectively). Survival at Stage III was highest in D‐0 phyllosoma (89%) and lowest in plain phyllosoma (51%). There was a positive relationship between phyllosoma AA concentration and larval survival (R² = 0.8328, P < 0.0001). D‐0 phyllosoma had the lowest stress index when subjected to an osmotic/temperature activity test, indicative of better survival in culture compared to plain, algal and D‐9 phyllosoma, which had consistently higher indices. A negative relationship existed between phyllosoma AA concentration and stress indices at Stage III (R² = 0.9263, P < 0.0001), suggesting that AA from the Artemia diet conferred stress resistance.     

The effect of photoperiod on growth, survival, colour and activity of juvenile southern rock lobster, Jasus edwardsii

Juvenile (1–10 g) southern rock lobsters, Jasus edwardsii, were subjected to five photoperiods [0L(light):24D(dark); 6L:18D; 12L:12D; 18L:6D; 24L:0D] during a 112‐day trial, and growth, survival, colour, food consumption and activity were examined. Lobsters grown under the 6L:18D and 24L:0D photoperiods had significantly lower (P < 0.05) final mean weight and specific growth rate than any other treatments. Photoperiod had no effect on survival or colour of lobsters. Food consumption differed significantly during the first week of the trial; after 5 weeks, food consumption was similar in all treatments. Major peaks in activity occurred during dark periods for lobsters exposed to photoperiods that had a light:dark regime. Activity of lobsters exposed to continuous light or dark regimes remained constant and at low levels during the 24‐h period. Food consumption or activity does not appear to determine the rate of growth of lobsters in the different photoregimes. One over‐riding outcome of this and other studies on photoperiod is that the growth and survival response of juvenile J. edwardsii was not significantly better than those of the standard 12L:12D cycle.     

Ingestion of artificial diets with different textures as determined by the inert marker ytterbium oxide during culture of early‐stage phyllosoma of the spiny lobster,Jasus edwardsii

Instar 1 and 2 Jasus edwardsii (Decapoda; Palinuridae) phyllosoma larvae were fed an artificial diet formulation (based on fish and mussel) consisting of three different gelatin combinations (firm, 4% inclusion; medium, 2% inclusion; and soft, no gelatin). The diet contained ytterbium oxide (Yb₂O₃; 1% inclusion), an inert heavy metal marker, which was used to confirm diet consumption in instar 1 and 2 phyllosoma. Over a 6‐h feeding period, instar 1 phyllosoma showed a preference for the soft and medium diets as opposed to the firm diet, but this effect was not significant with instar 2. The artificial diets remained palatable over the duration of the experiments, suggesting leaching did not influence diet attractiveness. It is suggested that diets comprising softer food items such as microencapsulated pellets or gelatinous formulated diets and pastes are most suitable for early‐instar phyllosoma. Furthermore, it is also suggested that Yb₂O₃ is a potentially useful marker for ongoing quantitative work on diet utilization in lobster larvae.     

Optimal feed pellet size for culturing juvenile spiny lobster Jasus edwardsii (Hutton, 1875) in New Zealand

There is intense international interest in the development of spiny lobster aquaculture and of particular interest is the development of artificial diets for spiny lobsters. However, there is little information on the feeding behaviour of spiny lobsters and their ability to handle and consume artificial feeds of different dimensions. Observations of the feeding behaviour of juveniles of the spiny lobster Jasus edwardsii in culture found that they waste significant amounts of food through externally fragmenting the feed pellets before sweeping particles into the mouth. The consumption efficiency of different sized pellets was found to change markedly with increasing size of the juvenile lobsters. Up to 50% of artificial food was wasted by the inefficient feeding behaviour of the lobsters. However, consumption of the feed could be reduced by as much as 19% by altering pellet size. These results indicate that the size of feed pellets, and their consistency and fragmentation characteristics, will be critical aspects of cost‐effective feeding of cultured spiny lobsters.     

Evaluation of Commercial Shrimp Grow-Out Pellets as Diets for Juvenile Southern Rock Lobster,Jasus edwardsii

Abstract

The growth, survival, and biochemical composition of juvenile southern rock lobster, Jasus edwardsii, were examined in response to a variety of diets, consisting of a natural food organism (blue mussel, Mytilus edulis) and/or commercial shrimp pellets. Blue mussel supported significantly better (a minimum of 25% higher) growth than a range of shrimp diets. Diet intake (0.83-1.26% wet body weight/day) and feed conversion ratio (1.34-2.48) with the formulated diets were generally similar to that with blue mussel (1.03% wet body weight/day; 1.55 feed conversion ratio). Changes in the chemical composition of southern rock lobsters due to treatments were more clearly observed in the digestive gland than in the whole body. Carapace color and tissue carotenoid level varied significantly with carotenoid content of the diets. A caro-tenoid level of 115 mg/kg is required in formulated diets to produce southern rock lobsters of similar color to wild-caught juveniles. In a separate experiment, a blue mussel diet was compared to mixed diets comprised of blue mussel and a shrimp, Penaeus monodon, diet. In the mixed diets, blue mussel was replaced with the formulated diet for either ×days/week or 6 days/week. Growth and survival did not differ significantly among treatments. The use of formulated diets in the culture of southern rock lobster appears feasible but will require increased knowledge of the nutritional requirements. Until specific diets are developed, this study has shown that similar growth can be obtained from a mixed diet, consisting primarily of a cheap formulated diet supplemented with blue mussel once per week. Such a scenario offers real possibilities for significantly reducing the cost of southern rock lobster production.     

Impact of wind stress anomalies on the seasonal pattern of southern rock lobster (Jasus edwardsii) settlement in South Australia

Quantified estimates of southern rock lobster (Jasus edwardii) puerulus settlement have been undertaken in the Southern Zone fishery of South Australia since the early 1990s. An analysis of mean monthly puerulus settlement indices from 1995 to 2007 in three monitoring sites revealed a strong seasonal correlation (r > 0.94 between sites) in settlement patterns. Settlement was highest during the winter months of June, July and August with peak settlement in all sites occurring in July. A reduced secondary settlement occurred during February and March. Seasonal trends were correlated with monthly wind stress and direction data in order to investigate possible environmental drivers of settlement. Using monthly averages of wind stress, it was hypothesized that strong along‐shore wind‐stress anomalies (ASWSA) prior to peak settlement would influence puerulus indices. Maximum ASWSA over the December–May period prior to maximum settlement was therefore examined. The results showed significant correlations (P < 0.1, r = 0.51–0.90) between wind stress and puerulus settlement in all but one site. We suggest that storm events, in combination with onshore surface drift during the period of settlement, are the principal physical oceanographic mechanisms influencing settlement patterns within the Southern Zone rock lobster fishery of South Australia.     

The effect of PUFA enriched Artemia on growth, survival and lipid composition of western rock lobster, Panulirus cygnus, phyllosoma

Western rock lobster, Panulirus cygnus, phyllosoma were grown from hatching to stage IV. Larvae were fed with Artemia enriched with a (i) base enrichment (Base) containing 520 g kg^?1 squid oil or tailor made enrichments in which oils high in polyunsaturated fatty acid (PUFA) have been added at the expense of squid oil. These treatments were (ii) base enrichment supplemented with docosahexaenoic acid (DHA) rich oil, (iii) base enrichment supplemented with arachidonic acid (AA) rich oil, or (iv) base enrichment supplemented with DHA and AA (D + A) rich oils. Total survival of phyllosoma to stage IV was high, with no significant difference between treatments (range 12.3–17.5%). By stage IV, the larvae fed the DHA or AA enriched Artemia were significantly larger (3.33 mm length) than larvae fed the Base or D + A enriched Artemia (3.18–3.24 mm length). Phyllosoma were sampled at stages II and III for biochemical analysis. The major lipid class (LC) in all phyllosoma was polar lipid (PL) (88.9–92.4%), followed by sterol (ST) (6.2–9.7%). Triacylglycerol (TAG), free fatty acid (FFA) and hydrocarbon/wax ester were minor components (≤1%) in all phyllosoma samples. In contrast, the major LC in all enrichments and enriched Artemia was TAG (76.3–85.1% and 53.4–60.2%, respectively), followed by PL (11.4–14.8% and 30.6–38.1% respectively). The main fatty acids (FA) in phyllosoma were 16:0, 18:1n‐9, 18:1n‐7, 18:0, AA, eicosapentaenoic acid (EPA) and DHA. Addition of AA, and to a lesser extent DHA, to enrichments resulted in increased levels of those FA in Artemia and phyllosoma compared with the Base enrichment. This was particularly evident for stage III larvae. Comparatively, elevated growth for phyllosoma to stage IV was achieved with DHA and AA enriched diets. Our findings highlight the importance of lipids and in particular essential long‐chain PUFA, as nutritional components for phyllosoma diets.     

Fatty acid profiles of spiny lobster (Panulirus homarus) phyllosoma fed enriched Artemia

Three different life stages of spiny lobster larvae (phyllosoma) of Panulirus homarus were fed A1‐Selco‐enriched Artemia in two culture treatments, one with the microalgae Nannochloropsis salina (green water) and the other without the microalgae (clear water) to assess the ability to manipulate their fatty acid composition. Phyllosoma fed with 3‐h A1‐Selco‐enriched Artemia salina attained Stage VIII (5.3 mm) and Stage V (3.4 mm) in 42 days in the green and clear water treatments respectively. The higher content of the essential fatty acids in N. salina (eicosapentaenoic acid, 25.8%; arachidonic acid, 9.5%; and docosahexaenoic acid, 4.2%) in the green water system increased the fatty acid content of the live food Artemia, and ultimately the phyllosoma. In spite of phyllosoma being fed with enriched Artemia in the clear water system, the total polyunsaturated fatty acid content of the early (Stages I–III) and mid stage (Stages IV–V) phyllosoma were significantly smaller (18.8% and 14.6% respectively) (P<0.05) than in the green water system (25.3% and 21.2% respectively). These results indicate the positive role of the microalgae in boosting the essential fatty acid content of lobster larvae.     

Morphological and biochemical characteristics of phyllosoma after photothermal manipulation of reproduction in broodstock of the spiny lobster, Jasus edwardsii

The consequences of photothermal manipulation of reproduction in Jasus edwardsii broodstock on the morphology of newly hatched larvae and their biochemical characteristics were examined. The treatment of compressed temperature and photoperiod delayed the time of moult, mating and egg extrusion, but reduced the period until larval hatch, and reduced the hatching duration in individual females compared to the ambient treatment of simulated natural photoperiod and water temperature. Thus, the availability of phyllosoma for hatchery rearing was extended. However, the broodstock in the compressed treatment produced smaller phyllosoma and more larvae failed to develop beyond the naupliosoma stage than animals from the ambient cycle. Phyllosoma from the compressed treatment contained a higher proportion of polar and triacylglycerol lipid classes, lower wax esters, elevated levels of the essential fatty acid docosahexaenoic acid, a higher ratio of n-3/n-6 fatty acids, and lower levels of ascorbic acid. The changes in larvae from the compressed treatment may adversely affect their viability, and are probably due to the higher water temperatures experienced during late embryonic development.     

Potential virulence factors of bacteria associated with tail fan necrosis in the spiny lobster,Jasus edwardsii

Tail fan necrosis (TFN) is a common condition found in commercially exploited spiny lobsters that greatly diminishes their commercial value. Bacteria possessing proteolytic, chitinolytic and lipolytic capabilities were associated with TFN in spiny lobsters, Jasus edwardsii. In this study, 69 bacterial isolates exhibiting all the three enzymatic capabilities from the haemolymph and tail fans of J. edwardsii with and without TFN were further characterized and compared, including morphology, biofilm formation, antimicrobial activity, antimicrobial resistance, and production of siderophores, melanin and ammonia. The genomic patterns of the most common Vibrio crassostreae isolates were also compared between TFN‐affected and unaffected lobsters. Biofilm formation was stronger in bacterial isolates from both haemolymph and tail fans of TFN‐affected lobsters compared to those from the unaffected lobsters, while melanin production and siderophore production were stronger in the isolates from tail fans of lobsters with TFN. By contrast, the other characteristics of isolates were similar in lobsters with and without TFN. The Vib. crassostreae isolates from the affected lobsters had similar genomic patterns. Overall, the results indicate that in addition to proteolytic, chitinolytic and lipolytic activities, the bacteria associated with TFN commonly have enhanced activity of important virulence factors, including biofilm formation, melanin production and siderophore production.     

Artemia prey size and mode of presentation: Effects on the survival and growth of phyllosoma larvae of southern rock lobster (Jasus edwardsii)

Performance of phyllosoma of thesouthern rock lobster (Jasus edwardsii)was examined after feeding Artemia-baseddiets. Survival and growth of newly-hatchedlarvae cultured to Stage III were lower(p < 0.05) when fed 0.8 mm Artemia than1.5 mm or 2.5 mm Artemia alone or 1.5 mmArtemia in combination with pieces ofmussel (Mytilus edulis planulatus) gonad.This could not be attributed to deficiencies inthe composition of fatty acids but appeared tobe due to the inability of larvae to capturesufficient appropriate-sized, enrichedArtemia for their nutritional requirements.There was an indication that survival andgrowth were higher between Stages III and Vwhen fed 2.5 mm Artemia than 1.5 mmArtemia alone or in combination with musselpieces. However, Stage VI larvae grew to asimilar size at Stage VIII when fed 1.5 mm or2.5 mm Artemia. Unexpectedly, larvae fedthe combination of 1.5 mm Artemia plusmussel supplement had lower survival than foundpreviously, and generally lower than when fed 1.5 mm Artemia alone. This was despitean apparent nutritional profile (lipid contentand fatty acid composition) of mussel more akinto that of newly-hatched phyllosoma thanenriched Artemia. On the other hand,survival and growth to Stage VIII were higherwhen larvae were fed alginate pelletscontaining Artemia than when fed 1.5 mmor 2.5 mm Artemia alone.     

Environmental influences on daily commercial catch rates of South Australia's southern rock lobster (Jasus edwardsii)

The extent to which catchability of southern rock lobster (Jasus edwardsii) due to short‐term environmental factors, rather than abundance, may be affecting legal‐size catch rates from the South Australian Southern Zone rock lobster fishery was examined. Multivariate weighted linear regression was applied to daily aggregated commercial catch rates using several environmental covariates in addition to year and month. Model pruning via backward selection identified the following variables as being significantly related to catch rate: wave height and period, lagged wave height, bottom temperature, moon phase, and a spatial block index. These variables explained 7% of the total variance in log‐transformed daily catch rates and another 84% was explained by month and year. A negative relationship was found between catch rate and each of bottom temperature and same‐day wave height, while the relationships between catch rate and days prior to full moon, and average wave height over the past 3 days were positive.     

The effects of krill hydrolysate-supplemented soya-bean based diets on the growth, colouration, amino and fatty acid profiles of juvenile American lobster, Homarus americanus

The feasibility of soya-based diets for pounded American lobster, Homarus americanus , was investigated using diets (40% protein) of low-fat soya-bean meal (SBM) containing various proportions of freeze-dried krill hydrolysate (FDKH) at 0, 12.5, 25, 50, 75, and 100% of dietary protein, in a 60-day trial using stage 5 juveniles. Diets of fresh blue-mussel, Mytilus edulis , and a diet of 100% of protein from fish meal (FM), approximating the industry diet of fish, were included for comparison. Specific growth rates (SGR) were not significantly different in all krill-containing diets, 100% FM and mussel diets. Juveniles on the mussel diet and the 75 and 100% FDKH diets had significantly higher maximum body weight gains (BWG), longer survivals (days in culture) and shorter moulting cycles. Juveniles deriving 100% of dietary protein from SBM failed to moult and had the lowest SGR and BWG, and the shortest survival period. Carotenoid content (mg kg⁻¹ dry weight), n-3 HUFA profiles (% of total fatty acids) and arginine (% of total amino acids) in the carcass correlated with dietary profiles (% of dry diet) and the level of dietary FDKH. Dietary SBM increased carcass 18:2n-6. Soya-bean meal supplemented with FDKH may provide up to 87.5% of dietary protein in artificial diets without compromising short-term BWG.     

Differing environmental drivers of settlement across the range of southern rock lobster (Jasus edwardsii) suggest resilience of the fishery to climate change

Temporal and spatial trends in settlement of the southern rock lobster, Jasus edwardsii, were examined to identify the influence of environmental variables over different spatial scales. Settlement data were collected from 1994 to 2011 along the Southern Australian and New Zealand coasts. We identified common settlement trends at a regional scale (100–500 km): the magnitude of settlement at sites from South Australia (SA) and Victoria (VIC) were similar, but different to sites in Tasmania (TAS). In New Zealand, three spatial regions were identified: northern (NNZ), middle (MNZ) and southern regions (SNZ). Higher settlement in SA, VIC and MNZ occurred in years with higher rainfall and storms in spring and El Niño conditions. In TAS and SNZ, higher settlement occurred during La Niña conditions. These results suggest that settlement over regional scales is modulated by oceanic processes, but outcomes vary between regions. At a local scale, a higher wave period and wind relaxation were relatively more important than the sea surface temperature (SST) in SA and VIC. In TAS, the current velocity also influenced the strength of settlement. However, much of the local settlement variability was not explained by the models suggesting that settlement in J. edwardsii is a complex process where larval behaviour, biological factors and oceanographic processes interact over different scales. The apparently complex processes affecting settlement showed that environmental conditions that reduced settlement strength in one region of the fishery often increased settlement strength in other regions. This could provide resilience to climate change at the stock level.     

中国龙虾叶状幼体摄食的研究

中国龙虾叶状幼体孵出后1－2h就开始摄食、其适宜的开口饵料为卤虫无节幼体，叶状幼体Ⅱ、Ⅲ、Ⅳ期摄食卤虫无节幼体后的变态率分别为80％、40％和32．5％。卤虫幼虫体和贻贝卵巢混合投喂，可提高叶状幼体的存活率。叶状幼体对不同饵料具有选择性，昼夜均可摄食，没有明显的摄食节律性。光照和黑暗对叶状幼体的摄食和存活没有影响。在适宜的卤虫无节幼体下，叶状幼体5－9min就可饱食，然后经过45－90min消化完毕；初孵叶状幼体对不同大小的卤虫无节幼体（349．5－604．9μm）的摄食没有明显差异，本试验可为开展中国龙虾的人工育苗积累资料。