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1.
Taiki Fuji Akihide Kasai Keita W. Suzuki Masahiro Ueno Yoh Yamashita 《Fisheries Science》2010,76(4):643-652
Juvenile temperate seabass Lateolabrax japonicus were sampled along the Yura River estuary from April to July 2008 to determine their distribution and feeding habits during
migration within a microtidal estuary. Throughout the sampling period, juvenile seabass were distributed not only in the surf
zone, but also in the freshwater zone, and they were particularly abundant in areas with aquatic vegetation in the freshwater
zone. This distribution pattern suggests that the early life history of the temperate seabass depends more intensively on
the river (freshwater) than previously considered. Small juveniles in the freshwater zone fed on copepods and chironomid larvae
and upon reaching a standard length (SL) of approximately 20 mm did they fed on mysids. In contrast, juveniles (approx. 17–80 mm
SL) in the surf zone fed mainly on mysids. 相似文献
2.
P. Domingues S. Garcia I. Hachero-Cruzado N. Lopez C. Rosas 《Aquaculture International》2010,18(3):487-499
The effects of two alternative prey (crayfish and hake) were tested on growth and survival of both juveniles and adults of
Octopus vulgaris in two experiments. Octopuses fed the control (squid) were larger (3.0 ± 0.7 kg) than those fed crayfish (2.4 ± 0.6 kg) at
the end of experiment I. Similarly, overall growth rates were higher for octopuses fed squid (1.7 ± 0.3 and 1.2 ± 0.2 %BW day−1, respectively). Average feeding rates for the experiment were not different, being 6.5 ± 0.9 and 7.5 ± 0.9 %BW day−1, respectively, for octopuses fed either squid or crayfish. Nevertheless, food conversions for the experiment were higher
(42.4 ± 2.7%) for octopuses fed squid compared to the ones fed crayfish (23.9 ± 1.9 g). For experiment II, hake and crayfish
were compared to squid; the final weight of octopuses fed squid, hake or crayfish was 1,183.0 ± 242.7 g, 1,175.6 ± 240.1 g
and 922.3 ± 160.1 g, respectively. Overall growth rates for the experiment were 1.9 ± 0.2 %BW day−1, 1.9 ± 0.3 %BW day−1 and 1.1 ± 0.3 g, respectively. Final weight and growth rates were never different (P > 0.05) between octopuses fed squid and hake, but were always higher (P < 0.05) compared to the ones fed crayfish. Average feeding rates for experiment II were similar for the three diets, and
of 4.6 ± 1.5, 4.2 ± 1.3 %BW day−1 and 5.1 ± 0.9 %BW day−1, respectively, for octopuses fed squid, hake or crayfish. Food conversions for experiment II were of 41.0 ± 9.6%, 40.5 ± 9.9%
and 21.3 ± 7.4 g, respectively, for octopuses fed squid, hake or crayfish, and were always higher for octopuses fed squid
and hake compared to crayfish. The results indicate that crayfish is not an adequate replacement for the usual prey to fatten
octopus, even considering its much lower market price. 相似文献
3.
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
4.
Gonzalo Perez Benavente Ingebrigt Uglem Ronan Browne Carlos Marino Balsa 《Aquaculture International》2010,18(6):1177-1189
A bottleneck for re-establishment or enhancement of lobster (Homarus gammarus L.) populations through release of hatchery-produced juveniles is ineffective and expensive juvenile production. In this
study, we cultured lobster juveniles from stage V to a size being suitable for re-establishment or enhancement purposes (40–50 mm
total length) in cages submerged under existing facilities for culture of bivalves. The lobsters were not feed or tended during
the culture period (6–14 months). The survival and growth rates were similar or higher compared to what has been achieved
with other methods used for culture of lobster juveniles in the past. The highest survival (82–89%) and fastest growth (4–5 cm
total length over 190–250 days) were achieved using commercial oyster baskets. It is believed that the juveniles fed on naturally
occurring plankton and organisms growing inside the cages. Thus, the current study shows that it is possible to culture lobster
juveniles for reestablishment or enhancement purposes in a way that would involve less investments and operational costs than
earlier used methods as there would be no need for artificial heating of water, for large buildings or for continuous feeding
and tending of large numbers of juveniles. 相似文献
5.
Yi Hu Beiping Tan Kangsen Mai Qinghui Ai Lu Zhang Shixuan Zheng 《Aquaculture International》2011,19(3):459-473
A 10-week feeding experiment was conducted to evaluate the nutritional value of menhaden oil (MO), soybean oil (SO) and soybean
lecithin oil (SL) at different ratios (MO/SO/SL) in practical diets for juvenile Litopenaeus vannamei by determining their effects on survival, growth, blood chemistry and fatty acid composition of hepatopancreas and muscle
tissue. Eight isonitrogenous and isolipidic diets were formulated using 3% MO(3/0/0), 3% SO(0/3/0), 3% SL(0/0/3), 1% MO + 1%
SO + 1% SL (1/1/1), 1% SO + 2% SL (0/1/2), 1% MO + 2% SL (1/0/2), 2% SO + 1% SL (0/2/1) and 2% MO +1% SL (2/0/1), respectively.
There were no significant differences in body weight gain among all treatments. However, shrimp fed diets with SL supplementation
showed significantly (P < 0.05) higher survival than those fed diets without SL supplementation (3% MO and 3% SO diets). The fatty acid (FA) composition
of hepatopancreas and muscle tissue reflected, to a certain extent, FA composition of the test diets. Shrimp fed the 3% SL
diets showed significantly (P < 0.05) higher triglyceride (TG) concentration in serum than those fed the other experimental diets. Shrimp fed diets containing
SL have relatively higher total cholesterol (TC) and phospholipid (PL) concentration in serum than those fed the diets without
SL (3% MO and 3% SO). The results of the present investigation are encouraging and confirmed soybean lecithin supplement in
shrimp practical diets, when sufficiently high levels of phospholipid are present, survival is enhanced. 相似文献
6.
Four semi-purified diets, containing crystalline amino acids (CAAs), were fed to juvenile red sea bream, Pagrus major in order to ascertain the ideal dietary amino acid pattern for this species. A control diet containing 50% casein–gelatin as protein sources, but no CAAs were fed to the fish. The other diets contained 30% casein–gelatin and 20% CAAs. CAAs were added to diets to simulate with amino acid pattern of the red sea bream eggs protein (REP), red sea bream larvae whole body protein (RLP), red sea bream juvenile whole body protein (RJP), and brown fishmeal protein (BFP). The juveniles (average initial body weight, 1.58 ± 0.01 g) were maintained in triplicate tanks and fed twice daily for 30 days. The highest weight gain was observed in juveniles fed the RJP diet. No significant difference was observed in juveniles fed the RLP and BFP diet. Feed efficiency ratio, protein efficiency ratio and amino acid retention in the whole body were significantly (p < 0.05) affected by the simulated dietary amino acid patterns. The essential amino acid profile and A/E ratios of the whole body after the growth trial showed little difference among the dietary treatments. The results suggest that red sea bream juveniles are able to utilize high amounts of CAA in coated form. The amino acid pattern of RJP could be used as an appropriate of reference dietary amino acid for this species. 相似文献
7.
Shude Xu Liang Zhang Qingyang Wu Xuebing Liu Shuqi Wang Cuihong You Yuanyou Li 《Aquaculture International》2011,19(5):1007-1018
In order to evaluate the feasibility of dried seaweed Gracilaria lemaneiformis (Bory) as a dietary ingredient for the rabbitfish Siganus canaliculatus (Park), juvenile fish (average weight 15.64 ± 0.15 g) were fed with two isonitrogenous (32% crude protein) and isolipid (8%
lipid) diets for 8 weeks, with one diet incorporating 33% of dried G. lemaneiformis (DGL), which accounted for 6% protein and 17% carbohydrate (DGL-diet), and the other containing no DGL (control diet). After
8 weeks, the growth performance and feed utilization efficiency of fish fed with the DGL-diet were inferior to fish fed with
the control diet, although some non-specific immunity parameters were better in fish fed with the DGL-diet compared with those
of fish fed control diet. Nutritional composition (whole body composition, amino acid, and fatty acid composition in dorsal
muscle) except methionine and tyrosine in muscle showed no differences between the two groups. Furthermore, the survival rate
of fish and apparent digestibility coefficient of diets were the same between the two groups. These results indicated that
incorporation of DGL in diet of S. canaliculatus is feasible, and further studies are recommended to optimize the level of DGL in diet of S. canaliculatus to improve growth performance. 相似文献
8.
Milagros R. de la Peña Myrna B. Teruel Jose M. Oclarit Mary Jane A. Amar Ellen Grace T. Ledesma 《Aquaculture International》2016,24(4):1103-1118
The effects of using thraustochytrid Schizochytrium sp. as source of lipid and fatty acids in a formulated diet on growth, survival, body composition, and salinity tolerance of juvenile donkey’s ear abalone, Haliotis asinina, were investigated. Treatments consisted of diets either containing a 1:1 ratio of cod liver oil (CLO) and soybean oil (SBO) (Diet 1) or thraustochytrid (Diet 2) as source of lipid and fatty acids at 2 % level. Natural diet Gracilariopsis heteroclada (Diet 3) served as the control. No significant difference in growth was observed in abalone fed Diet 3 (SGR: 5.3 % BW day?1; DISL: 265 μm day?1) and Diet 2 (SGR: 5.2 % BW day?1; DISL: 255 μm day?1). Survival ranged from 78 to 85 % for all treatments and was not significantly different from each other. A 96-h salinity stress test showed highest survival of 84 % in abalone fed Diet 2 compared with those fed diets 1 and 3 (42 %). The high growth rate of abalone fed Diet 2 and high tolerance to low salinity could be attributed to its high DHA content (8.9 %), which resulted to its high DHA/EPA ratio of 10.5 %. These fatty acids play a significant role in abalone nutrition. The fatty acid profile of abalone meat is a reflective of the fatty acid profile of the oil sources in the diet. The present study suggests that the use of Schizochytrium oil in lieu of CLO and SBO can support good growth of abalone which is comparable with abalone fed the natural seaweeds diet. 相似文献
9.
The effects of dietary mannan oligosaccharides (MOS) on the survival and growth of Astacus leptodactylus juveniles were evaluated. Experimental diets were prepared by using supplementation of 0 (Control), 1.5, 3.0, and 4.5 g MOS
kg−1 commercial trout larvae diet containing 43 g kg−1 protein and 15.74 g kg−1 lipid. A. leptodactylus juvenile with an average total length of 3.6 ± 0.46 cm (TL) and average weight of 1.25 ± 0.43 g was stocked in 0.2-m2 aquariums at a rate of 50 crayfish/m2 and reared for 60 days at 22.8°C. The experiment consisted of four treatments with three replicates each. Each aquarium contained
ten crayfish. Crayfish juvenile fed with 0, 1.5, 3.0, and 4.5 MOS attained 6.15 ± 0.49, 5.94 ± 0.29, 7.34 ± 0.39, and 5.94 ± 0.27 cm
final total length and 50, 56.67, 46.67, and 50% survival rates, respectively. Moreover, molting frequencies in 0, 1.5, 3.0,
and 4.5 g kg−1 MOS groups were detected as 44.44, 61.11, 83.33, and 38.88%, respectively. At the end of the experiment, a general enhanced
growth performance (P < 0.05) and feed conversion ratio were observed in crayfish fed on the diet containing 3.0 g kg−1. Crayfish juveniles fed with 3.0 g kg−1 MOS had the highest final length (7.34 ± 0.39 cm), although their survival was the lowest (46.67%) compared to other treatments
but not significant. Specific growth rates were significantly different (P < 0.05) among the treatment groups at the end of the 60-day experiment. There were no significant differences (P > 0.05) in percentage moisture, protein, and ash (wet-weight basis) in the tail meat of A. leptodactylus juvenile among treatments (diet) that averaged 82.3, 16.1, and 1.2%, respectively. However, lipid value was significantly
different among the diets P < 0.05), with values between 0.13 and 0.32. From the current results, it could be advised to use MOS at the rate of 3.0 g kg−1 in A. leptodactylus juvenile diets. 相似文献
10.
Tomoki Hashimoto Katsuya Hyodoh Takuma Hirose Satoshi Nishikawa Toshiya Katano Shin-ichi Nakano 《Aquaculture International》2008,16(4):309-318
In the pearl cultivation farms of the Ehime Prefecture, Japan, mass mortalities of the pearl oyster Pinctada fucata have occurred since 1994. The occurrences of mass mortality roughly coincided with a shift of the dominant phytoplankton
from Skeletonema and Chaetoceros to Chaetoceros and Nitzschia all of which belong to Bacillariophyceae. Hence, we evaluated Nitzschia, together with Chaetoceros and Isocrysis, as food for the oyster. Wet weights, lengths, widths, glycogen contents, and growth rates in terms of wet weight of the
oysters in all the feeding treatments were significantly higher than those in the non-feeding treatment. The highest glycogen
content (2.34%) and growth rate (2.21 g month−1) were found in the Chaetoceros treatment. Growth rate in the Isocrysis treatment (1.63 g month−1) was also high, although glycogen content in this treatment (0.41%) was low. In the Nitzschia treatment, growth rate of the oyster (0.94 g month−1) was the lowest and glycogen content (0.83%) was also low relative to that in the Chaetoceros treatment. Chlorophyll a concentration in fecal pellets was lowest in the Nitzschia treatment (<2.7 μg mg−1), suggesting more complete digestion of Nitzschia by the oyster. Thus, Nitzschia was edible and digestible but not assimilated by P. fucata. We propose the following scenario for the relationship between Nitzschia dominance and mass mortality. When Nitzschia dominates in a culture area, the physiological condition of P. fucata deteriorates due to low assimilation of Nitzschia by the oyster, followed by susceptibility of the oyster to infection by agents lethal to the oyster. 相似文献
11.
A field survey and a laboratory experiment were conducted to examine ontogenetic shifts in habitat and diet of the turban snail Turbo cornutus. The main habitat of turban snail juveniles smaller than 10 mm shell height (SH) was turfs of articulated coralline algae, and that of adults larger than 50 mm SH was kelp beds of Ecklonia bicyclis and Ecklonia cava. However, the ontogenetic habitat shift during the juvenile stage of 20–50 mm SH was unclear. From the results of a long-term feeding experiment and stable isotope analysis, the gelidiacean alga Gelidium elegans was assumed to be more important as a food source for juvenile turban snail than E. cava in the field. However, the frequency of individuals inhabiting gelidiacean algal turfs was low in both juvenile and adult stages. Thus, the ontogenetic shifts in habitat and diet did not coincide and other factors, i.e., daytime refuge, are important. As the growth rate was higher in the juveniles fed on the two algal species than those fed on single algal species, co-occurrence of various algal habitats in rocky shore ecosystems as a coastal ecosystem complex may enhance growth of turban snail juveniles feeding on a combination of different algal species. 相似文献
12.
Thomas H. Galley Frederico M. Batista Richard Braithwaite Jon King Andy R. Beaumont 《Aquaculture International》2010,18(3):315-325
The blue mussel Mytilus
edulis is a commercially important species whose fishery and culture generally relies on natural spat collection. Hatchery-production
could provide an alternative source of seed, enabling reliable expansion of the industry. Mussel spawning and larval rearing
trials were carried out to optimise elements of hatchery production. Culturing fertilised eggs at low density (20–200 eggs cm−2) rather than high density (400–720 eggs cm−2) significantly improved the quality of first veliger larvae and differences in this improvement were evident between the
eggs from different females (maternal effects). Veliger larval growth at 17 or 21°C was significantly faster than growth at
14°C. Feeding veliger larvae an identical total ration either daily or at 2–3 day intervals did not significantly affect their
growth. Different microalgal diets (1: Isochrysis sp. (clone T-ISO), 2: Chaetoceros
calcitrans forma pumilus, 3: C. muelleri, 4: mixed Isochrysis sp. (clone T-ISO) and C. calcitrans f. pumilus, and 5: mixed Isochrysis sp. (clone T-ISO) and C. muelleri) were tested on veliger larval growth and mixed diets outperformed single-species diets. 相似文献
13.
An 8-week feeding trial was conducted to evaluate the use of local poultry by-product meal (PBM) in replacement of imported
fishmeal in the diets of cobia, Rachycentron canadum. Six isolipidic (12%) and isoproteic (45%) experimental diets were formulated using PBM to replace fishmeal at 20, 40, 60,
80 and 100% dietary protein. Eleven juvenile cobia (initial mean weight of 30.7 ± 0.78 g) were randomly stocked in 300-L circular
fibreglass tanks and hand-fed based on the total biomass of each tank, twice a day at 0900 h and 1500 h. The fish were group
weighed at 2-week intervals to monitor their growth performance in order to adjust the feeding ratio. At the end of the feeding
trial, weight gains (WGs) ranging from 221 to 322% were obtained. The specific growth rate (SGR), WG and protein efficiency
ratio (PER) for fish fed with PBM-based diets were not significantly different (P > 0.05) when compared to fish fed the control diet. The best SGR was recorded for fish fed with 60PBM diet, which was significantly
higher (P < 0.05) than those fed the control diet with values at 2.40 ± 0.01 and 1.97 ± 0.26%/day, respectively. The FCR of 1.83 ± 0.05
for fish fed the 60PBM diet was not significantly different (P > 0.05) when compared to those fed the control diet. The PBM source and dietary level did not significantly (P > 0.05) affect the hepatosomatic index of the fish. The results from this study suggested that PBM could replace 100% dietary
fishmeal without adversely affecting the growth performance, but an optimal replacement level at approximately 60% was recommended
for better growth performance and efficient feed utilization. 相似文献
14.
The present experiment was conducted to determine the dietary total phosphorus requirement of juvenile yellow catfish Pelteobagrus fulvidraco. Six diets with increasing dietary phosphorus concentration (0.43, 0.55, 0.78, 0.90, 1.05 and 1.18% of dry matter, respectively)
were fed to triplicate groups of 20 fish each (mean initial body weight, 2.68 ± 0.08 g, mean ± SD) to apparent satiation for
7 weeks. Weight gain and specific growth rate (SGR) increased with increasing dietary phosphorus level from 0.43 to 0.90%
and then declined over dietary phosphorus level of 0.90% (P < 0.05). Phosphorus retention increased with increasing dietary phosphorus level from 0.43 to 0.55% and then declined over
dietary phosphorus level of 0.55% (P < 0.05). Dietary phosphorus levels significantly influenced whole body crude protein and ash contents (P < 0.05), but not whole body lipid content (P > 0.05). Vertebrae phosphorus content increased with dietary phosphorus level from 0.43 to 0.78% (P < 0.05) and then plateau over the level of 0.78% (P > 0.05). Dietary phosphorus level significantly influenced condition factor, viscerosomatic index and hepatosomatic index
(P < 0.05). The relationship between SGR and whole body ash content against dietary phosphorus levels could be expressed as
a second-order polynomial equation and the points of 0.89 and 0.85% were considered to be the optimal dietary total phosphorus
level, respectively. Based on broken-line analysis of vertebrae phosphorus content, the minimal dietary total phosphorus requirements
for maintaining maximum phosphorus storages were estimated to be 0.76% phosphorus. 相似文献
15.
Nilnaj Chaitanawisuti Tosapon Sungsirin Somkiat Piyatiratitivorakul 《Aquaculture International》2010,18(3):303-313
A feeding experiment was conducted to determine the effects of dietary calcium and phosphorus, and the interaction between
calcium and phosphorus, on the growth of juvenile spotted babylon, Babylonia areolata, cultured in a recirculating culture system. Nine isonitrogenous experimental diets supplemented with three levels of calcium
(1, 4, and 7%) for each of three levels of phosphorus (1, 3, and 5%) were prepared using fish meal, squid meal, and shrimp
meal as the main protein sources. Juveniles with an initial average body weight of 0.59 ± 0.09 g were fed to satiation once
daily with one of the nine diets for 180 days. Absolute and specific growth rates were calculated for both shell length and
whole wet body weight. Results showed that dietary calcium and phosphorus supplementation significantly affected the growth
of juvenile spotted babylon (P < 0.05), but not survival and feed-conversion ratio. The specific growth rate in shell length (SGRL) ranged from 0.32 to 0.39%
day−1. No significant difference among phosphorus levels and no significant interaction between calcium and phosphorus in SGRL
of the spotted babylon (P > 0.05) was found, but significant differences were observed among calcium levels, irrespective of phosphorus levels (P < 0.05). For 1 and 7% supplemental calcium, the spotted babylon had significantly higher SGRL than those fed diets supplemented
with 4% calcium. However, the specific growth rate in body weight (SGRW) ranged from 0.91 to 1.19% day−1 with no significant difference among calcium and phosphorus levels and no significant interaction between calcium and phosphorus
(P > 0.05). Survival and feed-conversion ratio were not significantly affected by dietary calcium and phosphorus levels with
ranges from 91.00 to 95.00% and 2.43 to 2.76, respectively. At the end of the experiment, shell abnormality of B. areolata was found for all feeding trials. 相似文献
16.
The effect of aqueous extract of Cratoxylum formosum on innate immune response and disease resistance in tilapia Oreochromis niloticus was investigated. The fish were fed diets containing 0% (control), 0.5% (diet 1), 1% (diet 2), and 1.5% (diet 3) of C. formosum aqueous extract for 30 days. At the end of the experimental period, parameters of innate immune response including phagocytosis
of blood leukocytes, lysozyme activity in plasma, and respiratory bust activity were examined. Feeding the fish with diet
2 and diet 3 for 20 days enhanced phagocytic activity and for 30 days stimulated lysozyme and respiratory burst activities.
Diet 1 increased the phagocytic activity at 30 days, but did not affect the other measured parameters. All parameters were
not significantly changed (P > 0.05) in the control group throughout the experiment. Following 30 days of feeding, fish were infected with S. agalactiae. The cumulative mortalities of bacterial-infected tilapia that were fed diet 1, diet 2, and diet 3 were 56, 12, and 10%,
respectively, compared with 85% in the control group. These results indicate that the aqueous extract of C. formosum may elevate the innate immune response and enhance disease resistance in tilapia. 相似文献
17.
We monitored feeding behavior and survival of starved juvenile olive flounder experimentally infected with the gill monogenean
Neoheterobothrium hirame. Infected flounder increased amount of the time spent in the water column by 117% when trying to capture live mysids, Neomysis sp. They also showed different feeding patterns from those of uninfected fish and made fewer attacks towards prey during
one feeding attempt. Although the average numbers of mysids captured by individuals were similar between infected and uninfected
fish, heavily infected fish tended to catch less prey. These results indicate that N. hirame reduces the feeding efficiency of the host for capturing live prey and possibly makes them more vulnerable to predation during
feeding. We could not detect any obvious difference in survival rates between uninfected, lightly and heavily infected fish
during 3 months of starvation. There was no evidence that starvation makes fish more susceptible to N. hirame. The present study provides first experimental evidence that N. hirame affects feeding behavior of juvenile olive flounder and supports the idea that this parasite indirectly reducing the host’s
survival and may be responsible for the recent reduction of the flounder population in Japan. 相似文献
18.
Pedro Domingues Ana Ferreira Lorenzo Marquez José P. Andrade Nelda López Carlos Rosas 《Aquaculture International》2008,16(3):215-229
The effects of feeding three natural frozen diets, grass shrimp (Palaemonetes sp.), crayfish (Procambarus clarkii) and fish (Sardina pilchardus) and two semi-humid artificial diets (based on fish powder) to mature cuttlefish, Sepia officinalis, were analysed. Growth and feeding rates (GR and FR, % BW day−1), food conversions (FC, %), and total protein and lipid composition of the diets were determined. Digestive gland to body
weight ratio and absorption efficiency were calculated for each diet. Cuttlefish fed shrimp and crayfish grew larger (1.5
and 1.1% BW day−1, respectively) compared to the other diets. Shrimp promoted the highest FC, followed by crayfish, and sardine. The highest
FR was obtained for cuttlefish fed crayfish (8.4% BW day−1). Although both artificial diets were accepted, none produced growth. A positive correlation (r = 0.96) between cuttlefish ingestion rate and digestive gland weight was obtained. Some cannibalism occurred among cuttlefish
fed the artificial diets during the last week of the experiment. According to the results obtained, P. clarkii could be used as an alternative prey to shrimp for rearing adult mature (>50 g) S. officinalis. 相似文献
19.
Carlos Rosas Ariadna Sánchez Cristina Pascual Josué Aguila Teresita Maldonado Pedro Domingues 《Aquaculture International》2011,19(1):165-180
Octopus maya is a carnivorous species and protein is the main energy source. During the present study, two different dietary protein levels
(40 and 60% CP) were offered to octopuses as specifically designed artificial diets, to determine protein needs and the effects
on metabolism. Frozen crab (Callinectes spp.) was used as control. Results obtained demonstrated that crab remains as one of the best diets for O. maya. The artificial diet with 60% CP produced a low but positive growth rate, and at times, a physiological response similar
to that observed in octopuses fed crabs. The present results show the capacity of O. maya juveniles to adjust their digestive enzymes to different types of food and protein level, and this appears to be well correlated
with octopus growth. General proteases and trypsin from the pancreas were well correlated with growth rates. A low activity
was observed in octopuses fed 40% PC diet (negative growth rate), while a high activity was present in octopuses fed 60% CP
diet and crabs (low and high growth rate, respectively). In contrast, these same enzymes were inducted in the salivary glands
of octopuses fed with the diet that promoted weight loss (40% CP diet), while a reduced activity was observed in octopuses
fed crabs. Energy budget indicates that the animals ingested more than 1,000 kJ week−1 kg−1; with such energy, octopuses should satisfy their physiological demands such as was observed when animals were fed crab (I = 1,300 kJ week−1 kg−1; P = 834 kJ week−1 kg−1). However, a very low digested energy was observed in octopuses the fed artificial diets, indicating that these could have
a factor that limits digestibility. 相似文献
20.
Taichi Masu Satoshi Watanabe Shigeru Aoki Satoshi Katayama Masaaki Fukuda Akinori Hino 《Fisheries Science》2008,74(1):41-47
ABSTRACT: The conventional acetate peel method was modified to analyze the shell growth pattern of juvenile Manila clam Ruditapes philippinarum as small as 2 mm in shell length (SL). In the outer shell layer along the axis of maximum growth, two types of growth increments were observed: distinct increments and indistinct increments, which, respectively, do and do not continue to the middle shell layer. The distinct increments were found to be formed every two days in intertidal and shallow subtidal zones by field enclosure experiments of juveniles with datum points marked with alizarin complexone. Growth patterns of juveniles (12 mm SL) collected from the Seaside Park of Yokohama in Tokyo Bay were analyzed to confirm the modified method. Mean daily shell growth rate from April to July 2005 ranged 120–142 μm/day, which was reasonable as compared with previous studies. It was impossible to backcalculate the growth to the settlement size (i.e. 0.2 mm SL) because of erosion of the outer shell surface, and the smallest backcalculated minimum shell length was 0.8 mm. Fluctuations in daily growth rate were high, ranging 29–315 μm/day, and did not show a clear two-weekly rhythm. 相似文献