首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 312 毫秒
1.
Development and design of adequate feeding protocols on sea cucumber larvae are necessary for improvements on larvae growth, survival and production of competent juveniles. This work assessed the Holothuria arguinensis larvae growth and survival, fed with three different single microalgae diets of Chaetoceros calcitrans, Isochrysis galbana and Tetraselmis chui, and two microalgae diets based on a combination of C. calcitrans and T. chuii (C:T; 1:1) and C. calcitrans, T. chuii and I. galbana (C:T:I; 1:1:1) during 2 months. Holothuria arguinensis larvae fed with T:C:I, showed higher survival and larger larval and stomach sizes than the ones fed with the other diets. Comparing the results obtained from the single diets, H. arguinensis larvae fed with I. galbana grew and survived better during the first 5 days. However, higher growth was obtained on the larvae fed with C. calcitrans from day 5 to day 12; since this day, larvae fed with T. chuii showed the largest size. These results could be related to the different microalgae size and morphology, in addition to the nutritional value of the different microalgae used. However, no competent larvae that metamorphosed into doliolaria were obtained during this experiment. The tanks used were transparent, which could be causing light stress to the larvae, since competent larvae were obtained in opaque production tanks in our aquaculture installations during the same time period. The combined diet of C. calcitrans, T. chuii and I. galbana (C:T:I) could improve the growth and larvae competency of H. arguinensis.  相似文献   

2.
This study assessed the nutritional value of four species of microalgae for larval sandfish, Holothuria scabra (Echinodermata: Holothuroidea). Two‐day‐old larvae were fed either a single diatom (Chaetoceros muelleri, Chaetoceros calcitrans), flagellate (Isochrysis aff. galbana (T‐ISO), Pavlova salina), or a ternary microalgal diet (TMD) comprised of 40% C. muelleri, 40% T‐ISO, and 20% P. salina for 12 d. On Days 4, 6, and 8 length of larvae fed either C. muelleri, C. calcitrans, or the TMD was significantly greater than in T‐ISO and P. salina fed larvae as well as the unfed control larvae. T‐ISO fed larvae had a significantly greater length compared to unfed larvae on Days 4, 6, and 8; however, larvae fed P. salina had a significantly greater length compared to unfed larvae on Days 6 and 8 only. Survival of larvae fed either C. muelleri or the TMD was significantly better than the flagellate fed and unfed larvae on Days 4, 8, and 12. There was no significant difference between survival of unfed larvae and larvae fed either T‐ISO or P. salina during the 12‐d larval culture period. On Day 12, larvae fed either a diatom or the TMD developed in excess of 84% competent doliolariae. Larvae fed C. muelleri had a significantly higher percentage competent doliolariae than larvae from all other treatments except the TMD. Neither larvae fed either T‐ISO or P. salina nor unfed larvae developed any competent doliolariae. In conclusion, this study showed C. muelleri to be the most effective of the four microalgae tested as a single microalgal diet for larval H. scabra and, as such, C. muelleri will be used as a reference diet in future studies.  相似文献   

3.
The effect of three mono‐specific and four combinations of the diatoms Chaetoceros muelleri, Chaetoceros calcitrans, and the chlorophyte Tetraselmis suecica on survival, development, and dry weight of the western school prawn, Metapenaeus dalli, was assessed from protozoea I until mysis I. The development and dry weight of larvae were significantly greater when fed diets comprising C. muelleri and/or T. suecica. A fourth diet, consisting of all three microalgal species also performed just as well. Survival alone was a poor measure of the performance of the various diets. Larvae fed with C. calcitrans, either alone or in a mixed diet with either C. muelleri or T. suecica, had significantly slower development and lower dry weight. Overall performance, assessed using the normalized biomass development index, determined that both mono‐specific and mixed diets containing C. muelleri and T. suecica were among the best for M. dalli larvae. These results for M. dalli are consistent with those found for commercially grown penaeid prawns. This study enhances the limited knowledge on the feeding requirements of metapenaeid prawn larvae. Moreover, the results will help improve hatchery methods for the aquaculture‐based enhancement of M. dalli in the Swan‐Canning Estuary and potentially increase the abundance of this iconic recreational species.  相似文献   

4.
The effect of docosahexaenoic acid (DHA) on the growth performance, survival and swim bladder inflation of larval Seriola dumerili during the rotifer feeding period was investigated in two feeding experiments. Amberjack larvae at 3 day post hatching were fed rotifers enriched with (1) freshwater C hlorella (Chlo), (2) a mixture (2:1, v/v) of Chlo and DHA‐enriched C hlorella (DHA‐Chlo), (3) DHA‐Chlo and (4) DHA‐Chlo and commercial DHA emulsion, in triplicate for 7 days. The average DHA contents of the rotifers were 0.0, 0.4, 1.0 and 1.9 mg g?1 DM respectively. The survival rate was improved by the enrichment of rotifers with DHA‐Chlo alone, and DHA‐Chlo and emulsion. Growth and swim bladder inflation of fish fed rotifers enriched with DHA‐Chlo were significantly (< 0.05) improved, however, with increased levels of DHA further improvement was not found. DHA content in the larval whole body proportionally increased with the DHA level in the rotifers. These results suggest that DHA enrichment of rotifers is effective to improve the growth, survival rate and swim bladder inflation of amberjack larvae. The DHA requirement of amberjack larvae is estimated to be 1.5 mg g?1 on a dry matter basis of rotifers.  相似文献   

5.
Black‐lip pearl oyster, Pinctada margaritifera broodstock was collected from the wild. Egg production, hatching rate and larval development were compared between oysters induced to spawn within 2 days after collection in the wild (T1), oysters fed a pure microalgae diet during 24 days before spawning (T2) and oysters fed the same microalgal diet in which 10% of the algae were replaced with 2 μm polyunsaturated fatty acid (PUFA)‐rich microspheres (T3). Administration of lipid microspheres resulted in larger sized eggs, a higher percentage of D‐larvae and larger sized 48‐h‐old larvae (P<0.05). The total and neutral lipid contents of the gonad increased after oysters were fed with microalgae only or with supplementary diet. The major neutral and polar fractions of saturated fatty acid (SFA) were 16C and 18C fatty acids, and not influenced by the diet (P>0.05). The gonads of oysters fed supplementary PUFA contained more docosahexaenoic acid (DHA) and less monounsaturated fatty acids. Higher level of DHA in gonads of T3 was associated with oogenesis and embryogenesis success. The n‐3/n‐6 ratio in the neutral lipid fraction provides a good indication of the spawning condition and predicting egg size and hatching rate.  相似文献   

6.
Gonadic conditioning and maturation of queen clam Dosinia ponderosa fed three microalgae (Isochrysis galbana, Tetraselmis suecica and Chaetoceros calcitrans) at three temperatures (20, 25 and 30°C) were assessed. Histological analysis showed six gonadic stages, indicators of maturity. The evaluation included sex proportion, oocyte diameter and frequency of gonadic stages after 22 (middle of trial) and 44 days (end of trial). At day 22, around 60% of females conditioned at 20°C, reached stage III (advances grade of maturation) when fed T. suecica. At day 44, around 50% of females were on stage III, conditioned at 20 and 25°C and fed T. suecica and C. calcitrans. For males, the best combination was C. calcitrans at 20 and 25°C. The temperature of 30°C resulted inadequate for maturation, especially when fed the diatom Isochrysis galbana. High mortalities occurred at that temperature with the three microalgal diets, especially in females. The results permits conclude that T. suecica and C. calcitrans are good sources of feed for D. ponderosa and that the best range of temperature for gonadic development is 22–25°C. These results may be basic for a best management and culture of this clam.  相似文献   

7.
To evaluate the possible dietary application of live and heat‐inactivated probiotic Bacillus pumilus SE5 in grouper Epinephelus coioides, juveniles (14.6 ± 0.2 g) were fed either a basal control diet (without probiotic) or the basal diet supplemented with 1.0 × 108 CFU g?1 live (T1) and heat‐inactivated B. pumilus SE5 (T2). The heat‐inactivated probiotic significantly improved the final weight, weight gain (WG) and specific growth rate (SGR) at day 60 and significantly decreased the feed conversion ratio (FCR) at day 30 and 60, while the viable probiotic significantly decreased the FCR at day 60 (< 0.05). Phagocytic activity, serum complement C3 and IgM levels as well as SOD activity elevated significantly in fish fed the heat‐inactivated probiotic for 60 days (< 0.05). Furthermore, the heat‐inactivated probiotic remarkably up‐regulated expression of TLR2 and pro‐inflammatory cytokines (IL‐8 and IL‐1β) in head kidney (< 0.05), but the viable probiotic failed to do so. These results indicated that heat‐inactivated B. pumilus SE5 can effectively improve the growth performance and immune responses of E. coioides.  相似文献   

8.
This study describes for the first time the cultivation of Cerastoderma edule on a commercial scale. A protocol to grow F2 generation cockles was developed, which led to fine‐tuning experiments for broodstock conditioning and spat growth. Broodstock animals were conditioned with diets of Isochrysis galbana (T‐Iso) or Tetraselmis suecica, whereas a third group was not fed. The best diet, T. suecica, induced 12 females out of 100 animals to spawn a total of 3 380 000 eggs. The non‐fed group did not spawn. Cockle spat (4.9 ± 1.0 mm) grew best when given a mixed diet of C. muelleri, T‐Iso and Sceletonema costatum, or a mixture of P. tricornutum and S. costatum at a concentration of 240 cells μl?1 day?1, resulting in a tripling of their wet weight after 14 days. The impact of density, burrowing substrate and food availability on cockle spat growth (41 days old, 5.6 ± 1.2 mm) was studied for 11 weeks. Best results were obtained by culturing spat at ad libitum food conditions at 500 ind m?2, resulting in an average growth rate of 168 μm day?1, an average final size of 19.0 ± 1.9 mm and a total final biomass of 1040 g m?2.  相似文献   

9.
Usual diets for rearing leptocephalus larvae of Japanese eel Anguilla japonica include eggs of the endangered spiny dogfish Squalus acanthias (SE). We investigated the effects of alternative food materials, hen egg yolk (HEY) and exoskeleton‐free (skinned) Antarctic krill (SAK), on the growth and survival of eel larvae. We found that feed comprising whole krill including exoskeleton (WAK) containing higher levels of fluoride (37.89 mg kg?1) was acutely toxic to eel larvae exposed to this alone. In contrast, extract from SAK containing lower concentrations of fluoride (4.25 mg kg?1) showed no apparent adverse effects. Growth of larvae fed a mixture of SE and SAK in a feed trial of 58 days [mean body weight (BW), 6.0 mg] was about twofold higher than that of larvae fed a mixture of SE and WAK (3.2 mg) (< 0.01). A mixture of HEY and SAK also had some dietary benefits for eel larvae, enabling them to survive for up to 58 days and to grow significantly (mean BW, 2.4 mg), compared with their initial weight (mean BW, 0.2 mg) (< 0.001). Although additional nutritional improvements are needed, the present results suggest that combination diet HEY and SAK may be a good alternative to SE as an effective diet for eel larvae.  相似文献   

10.
Considering the well‐known problems arising from the use of rotifers and Artemia as live prey in larval rearing in terms of fatty acid deficiencies, the aim of this study was to evaluate a partial or complete replacement of traditional live prey with preserved copepods during the larviculture of gilthead sea bream (Sparus aurata). Sea bream larvae were randomly divided into 4 experimental groups in triplicates: group A larvae (control) fed rotifers followed by Artemia nauplii; group B fed a combined diet (50%) of rotifers–Artemia and preserved copepods; group C fed rotifers followed by preserved copepods; and group D fed preserved copepods solely. Survival and biometric data were analysed together with major molecular biomarkers involved in growth, lipid metabolism and appetite. Moreover, fatty acid content of prey and larvae was also analysed. At the end of 40 days treatment, a stress test, on the remaining larvae, was performed to evaluate the effects of different diets on stress response. Data obtained evidenced a positive effect of cofeeding preserved copepods during sea bream larviculture. Higher survival and growth were achieved in group B (fed combined diet) larvae respect to control. In addition, preserved copepods cofeeding was able to positively modulate genes involved in fish growth, lipid metabolism, stress response and appetite regulation.  相似文献   

11.
The microalgae Isochrysis galbana and Chaetoceros muelleri were cultured with seaweed extract (SWE) from six different seaweeds and each SWE was used either as a supplement or as an alternative media to conventional f/2 medium. Microalgae cultured with only the f/2 media acted as the control treatment. I. galbana and C. muelleri were then fed to Penaeus indicus larvae, either singly or in combination, for 8 days to evaluate its nutritional quality. Shrimp larvae fed on microalgae cultured in f/2 media supplemented with SWE from Ulva lactuca or Enteromorpha intestinalis moulted faster (P < 0.05) to the second mysis stage compared with the control. Survival, total length and growth rates were better in shrimp larvae fed on microalgae previously cultured in media supplemented with SWE. In general, shrimp larvae fed microalgae cultured entirely in SWE performed equally well compared with the control. Shrimp larvae fed on mixed microalgae (I. galbana + C. muelleri) showed significantly better growth, survival and development compared with larvae on either single microalgal diet. It was concluded that microalgae cultured with SWE could be used as a low‐cost alternative media in producing live food for the hatchery production of shrimp larvae.  相似文献   

12.
The composition of protein, carbohydrate, lipid and fatty acids of the gonad of wild female broodstock of black‐lip pearl oyster, Pinctada margaritifera, was compared with oysters fed on a ternary combination of microalgae in hatchery. Artificial feeding was found to be as good as natural feeding in terms of number and size of released eggs. Lipid, protein and carbohydrate reserves of unfed oysters were found to be insufficient to complete oogenesis. The proportions of saturated fatty acids (SFA), monounsaturated fatty acids (MUFA) and polyunsaturated fatty acids (PUFA) of the neutral and polar lipids extracted from female gonads were not influenced by variations in the fatty acid composition of the natural food and ternary combination of microalgae in hatchery. T‐Iso, Chaetoceros calcitrans and Chaetoceros muelleri were able to provide sufficient 22:6n‐3 (DHA) and 20:5n‐3 (EPA), two of the most important essential fatty acids required for gametogenesis. The n‐3/n‐6 and 22:5n‐3/20:4n‐3 ratios were consistently higher in the neutral lipids than in the polar lipids. Conversely, the ratio of 20:4n‐3/20:5n‐3, 22:6n‐3/20:5n‐3 and PUFA/SFA was higher in the polar lipids.  相似文献   

13.
The surf Spisula solida and the striped venus Chamelea gallina clams support important fisheries in Europe. These fisheries have been affected by inter‐annual fluctuations in stock abundance and recruitment failures. Aquaculture could contribute to address these problems through the production of larvae or juveniles for stock‐enhancement programmes. In the present study, the prerequisites to produce these species in hatchery were established. Of the different methods used to obtain gametes (thermal stimulation, scarification and flow through), C. gallina spawned in the flow through only. By its turn, the best method for obtaining gametes for S. solida was stripping. Higher survivals of D‐larvae were found at 15 and 17°C. The greatest larval survival and growth rates were obtained from larvae fed Isochrysis aff. galbana (T‐iso). First C. gallina and S. solida pediveliger larvae were found at day 8 and day 26 respectively. The presence of metamorphosed larvae found even in the unfed treatment for C. gallina and for S. solida is an advantage for aquaculture production. After metamorphosis, the S. solida juveniles' survival was quite low, whereas there was no mortality for C. gallina juveniles reared without substrate regardless the diet provided. Juveniles fed the binary diet (Chaetoceros calcitrans ‐ C. cal + T.iso) and the monodiet T‐iso showed relatively higher growth in shell length and weight than C. cal. The hatchery production of these two species was possible, however the results of this study showed that C. gallina can be more attractive for aquaculture than S. solida.  相似文献   

14.
The effect of temperature (10, 13, 16, 19 and 22°C) on hatching, development and survival of yolk‐sac larvae of European hake, Merluccius merluccius, was studied. At 22°C the experiment was suspended because all eggs died a few hours after incubation. Five morphological indicators of larval development (standard length – SL, yolk‐sac volume – YSV, oil globule diameter – OD, body height – BH and body wet weight – BW) were analysed. SL, YSV, OD and BW of newly hatched larvae were biggest in size and weight at low temperatures (< 0.05). Throughout the experiments, the rates of changes in SL, YSV and OD varied with temperature (< 0.05). By contrast, BH and BW remained constant and did not show significant relationship with the effect of temperature (> 0.05). The potential model showed that the SL growth rate varied from 0.05 to 0.08 mm day?1 from 10.5 to 19.5°C respectively. However, at all temperatures two growth phases were identified: a rapid growth phase followed by a slow one. Rapid growth rate in length and depletion in yolk‐sac and oil globule occurred at high temperatures. After total YSV and OD consumption (death by starvation), larvae died between 8 and 14 days at 19.5 and 10.5°C respectively, reaching a maximum length of 4.3 mm at 10.5°C. Metabolic indices such as: lowest threshold temperature (T0); effective larval development (); cumulative thermal units (TC) to complete larval development; the temperature coefficient on growth rate in length (Q10) and the condition factor (K) were also studied.  相似文献   

15.
Several experiments were performed examining the effect of different culture variables on the growth and survival of Argopecten nucleus and Nodipecten nodosus larvae. Higher growth and survival values were obtained at a low density (1 larvae mL?1) than at a high density (5 larvae mL?1), except for N. nodosus's survival, which was not affected by density. Higher growth was obtained when feeding the larvae a diet of Isochrysis galbana, similar results occurred with the diet of Isochrysis galbana+Chaetoceros calcitrans in A. nucleus and with I. galbana combined with the lipid emulsion EmDHA in N. nodosus. Higher survival was obtained when the diet included a mixture of microalgae than when EmDHA was supplemented. Growth and survival of the larvae of A. nucleus were greater when fed continuously, while N. nodosus grew and survived better when food was given discontinuously. Higher growth and survival values were recorded at lower food concentrations ranging from 20 to 40 cells μL?1 of I. galbana. Higher growth was observed with increasing temperature between 22 and 28 °C, although there was a simultaneous decrease in survival. No significant effects on larval production parameters were found when the culture water was changed totally or partially, but higher larval growth of N. nodosus was verified when a partial renewal of water was performed.  相似文献   

16.
The supply of microalgae to hatcheries is a limiting factor for the mass larval production of sea cucumber (Apostichopus japonicus) in Fujian Province, China. In this study, Nannochloropsis sp. isolated from the East China Sea was tested as food for A. japonicus larvae. The first trial compared the effect of mono‐, bi‐ and trialgal diets comprising three microalgae (Chaetoceros muelleri, Dunaliella tertiolecta and Nannochloropsis sp.) on A. japonicus larval growth, survival, settlement and juvenile growth. The results showed that there were no significant differences in survival and settlement between larvae fed with Nannochloropsis sp. and other diets. All diet treatments yielded similar juvenile sea cucumber output. In the second trial, A. japonicus larvae were fed equally four times daily at three different rations (5000, 20 000 and 40 000 cells mL?1 day?1). Larvae fed 20 000 cells mL?1 day?1 were significantly larger than larvae in other groups and experienced the highest survival rate. In the third trial, A. japonicus larvae were fed 20 000 cells mL?1 day?1 in three different frequency (2, 3 and 4 meals day?1). The greatest body length was observed in larvae that received 3 meals day?1. Survival and settlement of larvae fed 2 meals day?1 were significantly lower than other two groups. These results suggest that Nannochloropsis sp. can be used as a diet for the large‐scale production of A. japonicus seed, and larvae fed three times daily at a ration of 20 000 cell mL?1 day?1 are recommended for hatchery production of A. japonicus.  相似文献   

17.
A 12‐week growth trial was conducted in a flow‐through system to determine dietary selenium (Se) requirement for on‐growing gibel carp (initial body weight: 76.2 ± 0.05 g, mean ± SEM). Selenomethionine was supplemented to the basal diet to formulate seven semi‐purified diets containing 0.26, 0.58, 0.72, 1.14, 1.34, 1.73 and 2.09 mg Se kg?1 diet. The results showed that plasma superoxide dismutase (SOD) activity significantly increased when fish were fed with 0.58 mg Se kg?1 diet (< 0.05) and then decreased at 2.09 mg Se kg?1 diet (< 0.05). Plasma T‐AOC activity was higher in fish fed with 0.72 mg Se kg?1 diet (< 0.05) and plasma malondialdehyde (MDA) was higher in fish fed with 0.26 mg Se kg?1 diet (< 0.05). When fish were fed 1.14 mg Se kg?1 diet, hepatic GSH‐Px, T‐AOC, GSH and CAT activities were significantly higher than those fed with 0.26 mg Se kg?1 diet (< 0.05). Hepatic superoxide dismutase (SOD) activity was higher at 1.34 mg Se kg?1 diet (< 0.05). Fish liver Se concentrations were significantly higher when fed with 0.72 mg Se kg?1 diet (< 0.05) and then kept constant when Se ≥ 0.72 mg kg?1 (> 0.05). Whole‐body and muscle Se concentrations were higher when fed with 1.34 mg Se kg?1 diet (< 0.05) and kept a plateau when Se ≥ 1.34 mg kg?1 (> 0.05). In conclusion, based on broken‐line regression of hepatic Se concentrations, hepatic SOD activity and hepatic T‐AOC activity, dietary Se requirements for on‐growing gibel carp was 0.73 mg kg?1, 1.12 mg kg?1 and 1.19 mg kg?1 diet respectively.  相似文献   

18.
The quality of the microalgae provided on Paracentrotus lividus larvae rearing is a primordial factor having a direct (nutritional properties) and indirect (water quality) impact on growth, competence and survival. Skeletonema costatum is a diatom commonly used in the bivalve cultivation. However, the use of this diatom in P. lividus larval cultivations is poorly known. The Rhodomonas spp. is a microalgae commonly used in sea urchin larvae culture. Three different diets were tested on P. lividus larvae and post‐larvae cultivation (D1—Rhodomonas marina, D2—S. costatum, D3—mixture of both algae). Larvae fed with the D2 diet (55.8%) and D3 (39.9%) had a survival at 15 DAH higher than D1 (5.5%). The low survival in D1 could be due to the higher microbiological load on microalgae (Vibrio alginolyticus and V. pectenicide). Larvae fed with S. costatum (D2) showed a lower development than other diets. The competency index was lower for larvae fed with the D2. These results show that microalgae diversified diets contribute to a better development of P. lividus larvae. During the settlement and post‐settlement phase, there was also a lower growth of the sea urchin fed with the D2 and a higher survival for D3.  相似文献   

19.
A feeding trial was conducted to determine the optimum dietary protein level of sea cucumber Apostichopus japonicus juvenile focusing on growth performance and non‐specific immune response. Diets with seven crude protein levels (42.0, 108.9, 155.2, 216.7, 258.0, 313.3 and 357.5 g kg?1) were fed to sea cucumber juveniles (1.05 ±0.01 g) once a day for 100 days. More than 70% survival was observed, and there was no significant difference among all treatments. The sea cucumbers fed diets containing 108.9 g kg?1 crude protein showed significantly (< 0.05) higher body weight gain than those of the sea cucumbers fed diets containing 42.0, 216.7, 258.0, 313.3 and 357.5 g kg?1 crude protein. No significantly differences (> 0.05) were observed in moisture, crude protein, crude lipid, ash and carbohydrate content of the body wall among all treatments. The coelomic fluid catalase activity of the sea cucumbers generally increased with increasing dietary protein levels. Therefore, the acid phosphatase, superoxide dismutase and lysozyme activity increased with increasing dietary protein levels at first and decreased subsequently. The relationship between dietary protein levels and body weight gain was analysed by a second‐order polynomial regression analysis model. The result indicates that the optimum dietary protein level for sea cucumber juveniles is 135.4 g kg?1.  相似文献   

20.
Clearance rate (CR) and ingestion rate (IR) of different sizes (89, 125 and 188 μm shell length) of Pinctada margaritifera larvae were determined when feeding on various microalgae. The microalgae tested were the diatoms, Chaetoceros muelleri and C. simplex, and flagellates, Tahitian Isochrysis aff. galbana, Pavlova lutheri and P. salina at 5 or 10 cells μL–1. Both CR and IR of microalgae tested in this study increased with increasing larval size; but at all larval sizes, diatoms resulted in lower CR and IR. Of the microalgae tested, P. margaritifera larvae showed greatest CR and IR with the two Pavlova spp. Maximum CR for P. salina was 10.5, 21.2 and 29.7 μL h–1 for larvae with shell lengths of 89, 125 and 188 μm, respectively. The highest IR values for P. margaritifera larvae with shell lengths of 89, 125 and 188 μm were 8.7, 81.0 and 165.7 cells·larva–1 h–1, respectively. CR and IR of P. salina were approximately five times higher than those recorded for C. muelleri and C. simplex.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号