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1.
A suspected new enteric Sphaerospora species was believed to be directly associated with the mass mortality of yearling groupers of Epinephelus spp. in South China. The epizootic generally emerged from late September to late April of the following year. The infection prevalence and mortality rate were significantly negatively correlated with fish size. Clinical signs included anorexia, cachexia and extrusion of white pulp‐like substance from anus after gentle pressure on the abdomen. Upon necropsy, severe intestinal oedema, thin and transparent intestinal wall, swollen spleen, kidney and gall bladder could be observed. Wet preparation of the infected samples showed large amount of typical disporous plasmodia of the genus Sphaerospora, but no mature spores were observed. Epidemiological investigation showed that this parasite exclusively infected Epinephelus groupers. Histopathologically, this species mainly infected the epithelium of intestine and kidney tubules and caused severe epithelia sloughing and the collapse of intestinal villus. Interestingly, this enteric myxosporidiosis did not cause severe emaciation of infected fish for mass mortality usually emerged within 2–3 days after appearance of clinical signs. The species was most genetically related to Sphaerospora fugu (89% sequence identity) and phylogenetically positioned within marine Sphaerospora lineage. This is the first report of enteric sphaerosporosis of groupers.  相似文献   

2.
Z Ding  Q Meng  H Liu  S Yuan  F Zhang  M Sun  Y Zhao  M Shen  G Zhou  J Pan  H Xue  W Wang 《Journal of fish diseases》2016,39(9):1043-1051
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3.
The effects of culture density and bottom areas on cuttlefish (Sepia officinalis) culture were studied. Cuttle fish were cultured under three experimental combinations of culture density and bottom area: (1) high density and small bottom surface area; (2) low density and large bottom area; (3) high density and large bottom area. Each experimental protocol was repeated in triplicate. Average weights at the end of the experiment were of 65.8 ± 5.8, 87.1 ± 5.6 and 78.7 ± 5.9 g for cuttlefish cultured under the conditions of protocol 1, 2, and 3, respectively; these differences were significant between each of the three groups. Total biomass increased faster (up to 7.5 kg per tank) under the high density/large bottom area conditions (protocol 3) due to the larger number of animals and low mortality in those tanks. Growth rates (%bw day−1) were different between protocols, with growth rates of 2.1 ± 0.1, 3.0 ± 0.2, and 2.5 ± 0.1%bw day−1 obtained for cuttlefish cultured according to protocol 1, 2, or 3, respectively. Average feeding rates were similar for the three groups—10.7 ± 0.8, 9.7 ± 2.0, and 9.6 ± 1.1%bw day−1 for cuttlefish cultured according to protocols 1, 2, and 3, respectively, while food conversions (%) were different—21.5 ± 3.2, 32.4 ± 2.5, and 27.0 ± 1.1%bw day−1, respectively. Total mortality was high in the high density/small bottom area tanks, 30%, while it was very low for the groups cultured under conditions of low and high density/large bottom area, 4%. Based on these results, we conclude that culture conditions that provide large bottom areas also provide good survival conditions and promote growth in comparison those with small bottom areas, even under conditions of lower culture densities.  相似文献   

4.
The effect of varying oxygen saturation regimes on growth and haematological profiles of peled Coregonus peled was investigated on fish of initial age 90 days post hatching. Eighty‐five juveniles per group (initial body weight 3.09 ± 0.80 g) were submitted to a 63‐day experiment with one of four water saturation regimes: normoxia (NORm, 80%–90%), hypoxia (HYPo, 50%–60%), hyperoxia (HYPe, 150%–160%) and intermittent hyperoxia (iHYPe, 150%–160% ‐ 80%–90%). Survival rate in NORm, HYPe and iHYPe ranged from 96.3 ± 2.1% to 97.7 ± 2.7, but survival 87.5 ± 3.0 was significantly lower in the HYPo group. No differences were observed in feed conversion ratio. The highest final body weight of 18.2 ± 4.6 g and a specific growth rate of 2.81 ± 0.01%/day were seen in the NORm group. Significant differences were found in haemoglobin concentration with increased saturation. The fish had lower haemoglobin 55.00 ± 5.72 and 51.35 ± 10.89 g/L in treatments HYPe, iHYPe with compared to the normoxia (64.22 ± 5.78 g/L). Haematocrit was similar in the groups HYPo, NORm and iHYPe (0.55 ± 0.04, 0.58 ± 0.05 and 0.54 ± 0.09) with the exception of HYPe, which was significantly lower (0.48 ± 0.06). Significantly lower count of erythrocyte was observed in iHYPe group (0.88 ± 0.20) with compared to the normoxia (1.06 ± 0.13). The supersaturation level was not associated with effects on growth and survival, and adding oxygen is not recommended for intensive rearing of peled. The results showed normoxia oxygen level to be the most suitable conditions for peled.  相似文献   

5.
The effects of different diets (natural or pellets) on growth, survival, and moulting interval of juvenile spider crabs, weighing between 0.011–1.56 g and up to 17.6 mm in carapace length, were tested over a period of 90 days. During experiment I, five diets were tested: (1) frozen shrimp—Paleomonetes sp., (2) fresh mussels—Mytilus sp., (3) white fish fillets—Merlucius merlucius, (4) blue fish fillets—Sardina pilchardus, and (5) commercial crustacean pellets. Spider crabs fed fresh mussels grew larger (0.98 ± 0.69 g) and had higher growth rates (4.0 ± 0.7 %BWd−1) compared to the other four diets. The crabs fed shrimp pellet and frozen shrimp grew to intermediate sizes and were smaller than the ones fed fresh mussels, but they were larger than spider crabs fed either blue or white fish fillets (0.46 ± 0.63 and 0.26 ± 0.13 g, respectively) compared to the ones fed white fish fillets (0.12 ± 0.04) and blue fish fillets (0.04 ± 0.02 g). The spider crabs fed blue fish fillets only lasted until day 60 of the experiment, after this day none of the 20 fed this diet were left. During experiment II, two diets were tested: (1) white and blue fish fillets and (2) commercial fish pellet. There were no differences in growth both in weight or carapace length (2.9 ± 1.8 and 2.1 ± 1.5 g in weight, and 18.9 ± 5.0 and 17.7 ± 3.3 mm, respectively) at the end of the experiment. Similarly, there were no differences in growth rates in weight between the two diets (1.2 ± 0.4 and 0.9 ± 0.3 %BWd−1, respectively) or in carapace length (0.4 ± 0.1 and 0.4 ± 0.2 %BWd−1, respectively). Fresh mussel appears to be a very good diet to culture the early stages of this species, while shrimp pellets also deliver acceptable results. On the contrary, frozen shrimp, fish fillets either from blue or white species (much higher lipid content in the blue species), and fish pellets were found to be bad diets for the culture of the early stages of M. brachydactyla.  相似文献   

6.
During the parasitological survey of cultured juvenile Pacific bluefin tuna (PBT) Thunnus orientalis in 2007 and 2008, two myxosporeans and one microsporidian were found. Morphological and molecular analysis showed that the heart-infecting and brain-infecting myxosporeans are identified as Kudoa shiomitsui and K. yasunagai, respectively. This is a new host record for both species. High prevalence of infection (77–100%) with K. shiomitsui was observed in October to December (1–2 months post-transfer to sea cages), whereas only a few fish were infected with K. yasunagai. A microsporidian observed as white “cysts” in the trunk muscle of PBT had a resemblance to Microsporidium seriolae, the causative parasite of beko disease in yellowtail. Phylogenetic analysis showed that the microsporidian from PBT is closely related to but distinct from several other muscle-infecting species such as M. seriolae, Microsporidium sp. RSB, and Microsporidium sp. SH. Additionally, the spore dimension (2.7 × 1.5 μm on average) was remarkably smaller than the others. These results suggest that the present microsporidian is an undescribed species and designated Microsporidium sp. PBT. Prevalence and intensity of infection with Microsporidium sp. PBT reached a maximum of 100% and 20 cysts/fish, respectively. Although pathogenic effects of the two Kudoa species on fish health remain unknown, the microsporidian could be of concern to PBT aquaculture due to unsightly cysts in the musculature, reducing the market value of the fish.  相似文献   

7.
Two groups of Apostichopus japonicus, a thermotolerant strain (group G3: wet weight, 64.22 ± 13.16 g/ind.), which was selected focusing on the performance of thermo‐tolerance through three generations for 10 years, and a control group (group C: wet weight, 62.08 ± 12.01 g/ind.) were collected from July to October in a seawater pond in northern China. Differences in relative faecal mass (RFM), relative intestinal mass (RIM), percentage of individuals with faeces (PIWF) and intestinal metabolites were investigated and compared between the two groups. The temperatures of terminating aestivation of the two groups were assessed according to the values of RFM and RIM. A regression analysis showed that the corresponding group G3 temperatures were 0.56–1.34°C and 0.70–1.49°C higher than those of group C when RFM and RIM were 0.01–0.05 and 0.005–0.025 respectively. The PIWF values in group G3 were 11.5%–21.2% higher than that in group C from 20 July to 22 September. Significant differences at the concentrations of 52 metabolites were detected between the two groups, 36 were higher in group G3 and 16 were higher in group C. The concentrations of threitol, 2‐methylglutaric acid, N‐acetyl‐D‐galactosamine, N‐acetyl‐L‐leucine, lactose, oxoproline, 2,3‐dimethylsuccinic acid and d‐glucoheptose were significantly different between groups G3 and C and were considered metabolic markers distinguishing group G3 from group C. Metabolism of A. japonicus in group G3 was more active than that in group C. These results provide new insight for understanding ingestion and intestinal metabolism in the thermotolerant strain of A. japonicus under high summer temperature.  相似文献   

8.
Seriolella violacea, a new species to be potentially farmed in Chile and Peru, has shown cranial malformations during farming that could adversely affect its commercial development. This study seeks to generate early knowledge of the osteological development and type of cranial abnormalities that this species presents under culture conditions. Larvae from wild caught broodstock were reared from 1 to 60 days post hatching (DPH) (4.8 ± 0.1 mm TL and 11.8 ± 1.0 mm TL respectively). Larvae samples were collected throughout the experimental trial for recording cranial osteological development and abnormalities in cartilage and bone. At 5.7 ± 0.1 mm TL, coraco‐scapular, sclerotic, ethmoid plate and quadrate cartilages were present. At 8.0 ± 0.6 mm TL, early ossification was observed in the jaw, premaxilla and maxilla. At 11.8 ± 1.0 mm TL, the branchiostegal rays, jaw, maxilla and opercular complex were ossified. The first cartilaginous structures observed were the Meckel's cartilage, the branchial arches and the suspensory ligament. The first cranial malformations were detected at 5.7 ± 0.1 mm TL, coinciding with mouth opening. The most frequent malformations were a curvature of the lower jaw (23.1%), abnormal separation between branchial arches and the Meckel's cartilage (19.4%) and bulging jaws (15.7%).  相似文献   

9.
The growth, survival and influence of environmental factors were analysed in two cohorts of cultured Pteria sterna in Ayangue Bay, Province of Santa Elena, Ecuador (tropical Eastern Pacific). Juveniles representing cohorts I and II (8.4 ± 0.54 and 5.0 ± 0.17 mm in dorso‐ventral axis) were deployed in November 2015 and February 2016, and grown in pearl nets suspended in a long line for 12 and 10 months respectively. The stocking density was monthly and bi‐monthly reduced during sampling of individuals to determine growth in dorso‐ventral shell axis, dry mass of shell, soft tissues and dry mass of fouling on shell. Water temperature, salinity, total seston and phytoplankton biomass (chlorophyll a) were determined at the culture site. Results showed that P. sterna reached ~100 mm in length during the first year of culture. Although little negative influence of environmental factors was detected, high temperatures during the reproduction period can be the most negative influential trait. The highest tissue mass (6 g), which occurred at the 10th month of cultivation, as well as a high availability of spat by artificial collectors in the coastal waters, showed that the species can be considered a good candidate for aquaculture in the tropical eastern Pacific.  相似文献   

10.
The genus Megalocytivirus is known to infect a wide range of cultured marine fish. In this study, we examined the pathogenicity of FLIV (Megalocytivirus from olive flounder, genotype III) and RBIV (Megalocytivirus from rock bream, genotype I) to their homologous and heterologous host species. Olive flounder (7.5 ± 1.3 cm) injected with FLIV [major capsid protein (MCP) gene copies, 6.8 × 103–6.5 × 106/fish] at 24 °C did not die until 90 days post‐infection (dpi). The average virus replication in the spleen peaked (1.27 × 106/fish) at 20 dpi. Rock bream (6.5 ± 1.5 cm) injected with FLIV (8.8 × 105 and 6.5 × 106/fish of MCP copies) showed no mortality until 50 dpi. The rock bream that survived after FLIV infection were rechallenged with RBIV at 50 dpi had 100% mortality, showing that there is no cross‐protection between FLIV and RBIV. Temperature shifting (26 °C and 20 °C at 12 h intervals) did not cause FLIV‐specific mortality into olive flounder, but higher virus copies were observed in the fish exposed to higher stocking density. This study demonstrates that FLIV and RBIV have different antigenic and pathogenic characteristics and that FLIV has low pathogenicity to olive flounder.  相似文献   

11.
The effects of different salinity levels, including 10–15, 30–35, 70–75, 110–115 and 150–155 ppt, were evaluated on survival and the body amino acids (BAA) of Artemia franciscana. The results were expressed as total essential (TE), non‐essential (NE) and total amino acids (TAA); also, the ratio of the TE to NE (ENAA) on days 3 and 13 of the culture is reported. The study of changes in Artemia BAA showed that with the increase in the water salinity, the TE, NE and TAA increased significantly on days 3 and 13 of the culture. However, the highest ratio of ENAA was observed in the 110 gL?1 salinity treatment on day 3 (1.067 ± 1.25). Regarding the effects of different salinity treatments on the survival rate of Artemia, it was observed that, generally, an increase in the water salinity would reduce the survival rate of this species. This reduction was observed on day 3 of culture in the salinity treatments above 120 (66.66 ± 1.68%) and below 30 gL?1 (89.66 ± 0.34%) and on day 13 of culture in the salinity treatments below 30 (11.86 ± 0.13%) and above 70 gL?1. Basically, it can be concluded that A. franciscana culture at a salinity of 110 gL?1 can lead to the biological enrichment of Artemia in terms of amino acid profile.  相似文献   

12.
Ninety‐seven specimens of spotfin hatchetfish, Thoracocharax stellatus, an ornamental freshwater species from the Amazon basin, were captured in the basin of the Guamá River in the municipality of Belém, in northern Brazil, and analysed for coccidiosis infection. Overall, 26 of the specimens were infected by apicomplexan parasites of the genus Goussia, with unsporulated forms being found in the gastric epithelium and sporulated forms in the intestinal lumen. The spheroid oocysts (mean diameter: 13.2 ± 1.7 μm) have four elliptical sporocysts. A partial sequence of the SSU rDNA of the new species was obtained, which contained 1,121 base pairs, with 43.8% guanine + cytosine (G + C), and the bases distributed as follows: A = 28.1%, C = 18.3%, G = 25.5% and T = 28.1%. The combined analysis of the morphometric and phylogenetic evidence confirmed that the specimens represented the genus Goussia and were allocated to a new species, Goussia guamaensis n. sp., which is described here.  相似文献   

13.
Bovine colostrum, an alternative food of animal origin provided as partial protein source, may constitute an innovative ingredient in fish feeding. Serum insulin‐like growth factor 1 (IGF‐1) and cellular activity of enteric, hepatic and muscle tissues of juvenile pacu Piaractus mesopotamicus fed with lyophilized bovine colostrum (LBC) were evaluated. Pacu (8.46 ± 0.74 g; 7.75 ± 0.27 cm, n = 18 in triplicate) were stocked into 18 tanks (300 L; 18 fish per tank, in triplicate) and fed with control diet containing 0% of LBC or experimental diet containing 10% and 20% of LBC inclusion for either 30 or 60 days of experiment. IGF‐1 serum concentration was not affected (P > 0.05) by the diet containing LBC and experimental period. The intestinal and hepatic cellular activity was not influenced by LBC (P > 0.05); however, intestine protein/RNA decreased at 60 days (P < 0.05). The muscle cellular activity was affected by LBC, highest in fish fed with diet containing 10% of LBC (P < 0.05). Between the periods DNA and protein/RNA increased at 60 days, while RNA, protein/DNA and RNA/DNA ratio decreased in this same period (P < 0.05). Increased DNA muscle content indicates fish growth by hyperplasia. The results of the present study is related with suitable development of enteric, hepatic and muscle tissues and proper condition of juvenile pacu fed with LBC considering the absence of differences in relation to juveniles that consumed diet without colostrum.  相似文献   

14.
The culture‐based fishery of Liangzi Lake, Yangtze River Basin, established in 1992, yielded 2,652 t/year (±167) between 2005 and 2015, dominated by stocked carps [Hypophthalmichthys molitrix (Val.) and Hypophthalmichthys nobilis (Richardson)] and mitten crab Eriocheir sinensis (Milne Edwards), accounting for 53% and 23% of the production and 20% and 52% in value, respectively. The lake had a macrophyte cover dominated by Vallisneria natans (Lour.) Hara with a cumulative biomass of 10,647 g/m2 that disappeared after a major flood in 2010 and changed its ecology. Management changes in stocking strategies introduced in the post‐flood period enabled the culture‐based fishery to maintain viability and sustainability to combat the major ecological change in the lake. The stocked species contributed significantly to nutrient removal of 24.71 ± 5.12 t/yr and 6.29 ± 0.87 t/yr of total nitrogen and total phosphorus, respectively.  相似文献   

15.
Meagre (Argirosomus regius) is a relatively new farmed fish species in Croatian mariculture. This study is the first attempt to determine the prevalence of cymothoid isopod parasite Ceratothoa oestroides and its effects on cultured meagre in the Mediterranean area. When analysing growth of meagre at two sites in the central part of the Eastern Adriatic Sea, the greatest difference in total fish length was recorded in March 2016, when fish with parasites were 33% smaller than fish without parasites (24.47 ± 3.29 vs. 16.28 ± 1.01 cm; p < .001). The largest difference in mass was also recorded during sampling in March, when parasitized fish was 74% lighter than the unparasitized fish (171.75 ± 72.96 vs. 44.77 ± 6.57 g; p < .001). The presence of the cymothoid isopod in the buccal cavity was observed, and caused fish deformation throughout the entire duration of the study. Also, female parasites with pulli II in marsupium were found. Based on the determined prevalence and effects on production and health status, monitoring of the interaction between C. oestroides and meagre should be considered in future management plans for cultivation of this promising species for Mediterranean aquaculture.  相似文献   

16.
Copepods are crucial source of live feeds in the aquaculture industry. In particular, several species of the genus Acartia are considered optimal prey for fish larvae. The species Acartia bilobata has excellent potential for marine larvae culture, as it is easy for mass culture. This study investigated the effects of various algal diets on the egg production and egg‐hatching rate of A. bilobata. The results indicated that the single‐species diet Isochrysis galbana was the most supportive diet for A. bilobata egg production and female life span in all treatments (egg production: 23.85 ± 0.70 eggs female?1 day?1 and female life span: 18.00 ± 1.45 days). Nannochloropsis oculata and Tetraselmis chui treatments gave markedly lower egg production and female life span as both single‐species and multiple‐species diets. For the egg hatching‐rate experiment, except for the T. chui treatment, which yielded a considerably lower hatching rate than the other diets, the hatching rate was only slightly affected by the algal diets. These results confirm that A. bilobata, a tropical brackish‐water copepod species, develops rapidly at 28°C and can produce a large number of eggs; therefore, it has considerable potential for larvae culture.  相似文献   

17.
The purpoase of this research was to test the effects of three culture densities on the growth and survival of Octopus vulgaris. A total of 141 sub-adult octopuses (1,175.4 ± 194.9 g) were randomly distributed in nine tanks of 2,000 l each (3.6 m × 1.1 m, and 50 cm water depth). Three tanks were stocked with a low initial density of 4 kg/m3, while three other tanks were stocked with an initial density of 8 kg/m3, and the remaining three tanks were stocked at an initial density of 15 kg/m3. Octopuses were all fed frozen squid (Loligo gahi) at 5% body weight per day (%BW/day). The experiment lasted for 70 days. Water temperature varied between 20 ± 2°C, and salinity varied between 36 ± 1 ppt. During the entire experiment, dissolved oxygen was always >75%, and ammonia was always lower than 0.1 mg/l. No differences in growth or growth rates (between 0.9 and 1.1%BW/day for the three densities) were found. Nevertheless, mortality was significantly lower for the low density compared to the other two densities tested. Maximum densities in the culture tanks (>25 kg/m3) were attained in the higher culture densities after 56 days of the experiment.  相似文献   

18.
In the present study, we report the first successful instance of controlled reproduction in Scatophagus argus, which has recently emerged as a new aquaculture resource. The controlled reproduction process for S. argus was optimized with regard to salinity acclimation. Gonadal maturation was affected by salinity in both sexes. Levels of plasma 17β‐estradiol (E2) and 11‐ketotestosterone (11‐kT) were salinity dependent and increased significantly with the duration of acclimation. Plasma levels of gonadal steroids were higher in fish held at 25‰ salinity. The highest gonadosomatic indices (GSI), 15.1 ± 1.6 in the female and 6.4 ± 1.2 in the male, were also observed at 25‰ salinity. Nevertheless, the optimal salinity for S. argus embryonic development and larval culture was 15‰. Thus, the salinity requirement for gonadal maturation and early development are quite different. The use of advanced reproductive technologies combining salinity acclimation and stimulation of luteinizing hormone‐releasing hormone analog (LHRH‐A2) resulted in a fertilization rate of 83.2%–91.3% and embryonic survival rates of over 90%. Embryos of S. argus at the 2‐cell, blastula, gastrula and pharyngula stages were observed. Most embryos hatched after 21.0 hr of incubation at 28.0 ± 1.0°C. The development of larvae into juveniles was completed at 40–45 days posthatch (dph). In this study, we provide information about the controlled reproduction of S. argus and identify the optimal environmental parameters for S. argus embryonic and larval culture, with the aim of developing reliable reproductive techniques for its mass production.  相似文献   

19.
The effects and commercial implications of aquatic plant addition, and variable prawn stocking density and supply of commercial aquafeed on water quality, prawn production and economic benefit, are investigated in a prawn (Macrobrachium rosenbergii) + plant (Hydrilla verticillata) co‐culture system. Our experimental design includes a control (PM, prawn monoculture without H. verticillata, with 30 prawns/m2) and four treatments with 15% plant cover of total pond area in each replicate. Dissolved oxygen, pH, N, P, total ammoniacal nitrogen, nitrite and nitrate in this co‐culture system were significantly lower than those of PM. Prawn survival (96.2 ± 14.9%), average final weight (68.5 ± 4.9 g) and yield (879.1 ± 102.4 kg/ha) in treatment 20W80%A (20 prawns/m2, 80% of control aquafeed) were obviously greater than in PM and other treatments. Despite small males (SM) and immature females (IF) being predominant in prawn + plant cultures, more than 77.2% of prawns reached or exceeded 40 g on completion of trials, and by six months were of appropriate size for market. We report culture of M. rosenbergii with H. verticillata to be both feasible and profitable. The optimal treatment, a stocking density of 20 prawns/m2 with these plants, enabled reduction of commercial aquafeed to 20% conventional culture levels. For this optimal treatment, we estimate total gross revenue, profit and internal rate of return to be US$ 6,593.3 ± 103.3 ha?1, US$ 3,095.5 ± 42.6 ha?1 and 127.5 ± 20.7% for 20W80%A respectively; we estimate U.S. Dollar (US$) invested generates 3.87 times conventional culture revenue. Co‐culture of M. rosenbergii and plants renders prawn production ecologically and economically feasible on larger farms.  相似文献   

20.
Calanoid copepods, including species of the genus Acartia, are commonly used as larval diets for marine finfish. This study aimed to determine the separate effects of water temperature (18, 22, 24, 28° ± 0.5°C) and photoperiod (24L:0D; 18L:6D; 12L:12D; 8L:18D; 0L:24D) on Acartia grani egg production (EP), hatching rate (EHR) and population growth. Egg production rate was not affected by the two abiotic parameters. A. grani eggs incubated at T24°C and T28°C were the first to achieve 50% hatching rate (23–25 hr), with significant differences at the end of the experiment (48 hr) between T28°C treatment (EHR 88 ± 5%) and T18°C treatment (EHR 65 ± 2%). However, different temperature regimes did not affect final number of individuals in population growth experiment. Still, when eggs were excluded from data, population at lower temperatures (18°C) was mainly composed by the nauplii stage (72%), while at higher temperatures (24°C and 28°C) more than 60% of the population was composed by copepodites and adults. A. grani subjected to long‐day photoperiods had significantly lower EHR (16.7% at 24L:0D; 20.8% at 18L:6D) than at short‐day photoperiods (52.6% at 6L:18D; 50.0% at 0L:24D). In population growth experiment, eggs were the most common life stage after 12‐day culture. Lowest population number was found at constant light conditions (665.0 ± 197.1), suggesting higher metabolic rates and depletion of energy reserves in long‐day conditions. This study expanded knowledge on the biological response of A. grani to separate temperature and photoperiod regimes, and provided ground to improve the culture of this potential life feed species for hatcheries.  相似文献   

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