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1.
In the present study, we developed a larval anchovy growth model in relation to sea temperature and food availability via food consumption and metabolic process terms, based on biological data from previous laboratory experiments and field surveys from 2003 to 2006 in Hiuchi-nada Sea, central part of Seto Inland Sea, Japan. To investigate when food shortage for larval anchovy and then recruitment failure occur in Hiuchi-nada Sea, anchovy food requirements were estimated by using the growth model, and we compared the food requirement with anchovy food availability. We applied an estimation method for growth model parameters, Hewett?CJohnson p and Q 10, by minimizing the sum of squares of difference between mass-specific growth rates estimated by the models and those by otolith growth analysis. Parameter p was 0.86, slightly higher than typical values, and Q 10 was 2.11, close to the value used for the biological model of larval northern anchovy. Food shortage for anchovy larvae did not occur in Hiuchi-nada Sea, although it was indicated that low food availability led to a low reproductive success rate. The newly developed growth model is considered optimal at present and useful to link environmental conditions and larval growth. 相似文献
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3.
以1~6月龄三疣梭子蟹"中宁1号"为材料,采用Logistic、Gompertz和von Bertalanffy3种模型分别拟合了体质量、体长、全甲宽、甲宽、体高、大螯长节长、大螯不动指长及第一步足长节长共8个形态性状的生长特征,旨在寻找各性状的最佳生长模型,并对其增长规律进行研究。结果表明:三疣梭子蟹体质量性状生长过程以Logistic生长模型(R2=0.999)的拟合效果最佳;除体质量外的其它7个性状则均以von Bertalanffy生长模型(R2为0.990~0.994)拟合效果最好;各性状模型经ANOVA检验后均具有统计学意义(P0.01)。根据各性状的最佳生长模型得出各性状的极限值分别为体质量231.44 g、体长84.45 mm、全甲宽164.44 mm、甲宽128.47 mm、体高43.69 mm、大螯长节长59.96 mm、大螯不动指长90.89 mm、第一步足长节长37.20 mm。体质量的快速生长区间及拐点分别为2.14~3.91月龄及3.02月龄;其它7个性状快速生长区间的始速点为0月龄,终速点为2.05~2.35月龄,拐点在1月龄左右。各性状间的生长速率、生长加速率、相对增长率与绝对增长率存在一定差异。总之,体质量性状生长过程符合"慢-快-慢"的特征,其它性状则表现为"快-慢"的特征。以上结果可为三疣梭子蟹"中宁1号"选择育种及养殖生产提供参考依据。 相似文献
4.
The present study is a first step towards evaluation of the potential for line-mussel production in the Great Belt region between the Kattegat and Baltic Sea, Denmark. We present experimental results for actual growth rates of juvenile/adult mussels Mytilus edulis in suspended net bags in terms of shell length and dry weight of soft parts during extended periods (27–80 days) in the productive season in the first 6 series of field experiments, including 4 sites in Great Belt and 2 sites in Limfjorden, Denmark. Data were correlated and interpreted in terms of specific growth rate (μ, % day?1) as a function of dry weight of soft parts (W, g) by a previously developed simple bioenergetic growth model μ = aW ?0.34. Results were generally in good agreement with the model which assumes the prevailing average chlorophyll a concentration at field sites to essentially account for the nutrition. Our studies have shown that M. edulis can grow from settlement in spring to 30 mm in shell length in November. We therefore suggest line farming of 30 mm ‘mini-mussels’ during one growth season, recovering all equipment at the time of harvest and re-establishing it with a new population of settled mussel larvae at the beginning of the next season, thus protecting the equipment from the damaging weather of the Danish winter season. The growth behavior during the fall–winter season was recorded in an additional 7th series of mussel growth experiments on farm-ropes to show the disadvantage of this period. 相似文献
5.
A model for fish growth simulation based on the bioenergetic factorial approach is presented. This work presents a novel approach that extends the traditional bioenergetic model by explicitly including the Energy and Protein fluxes (EP model). This is a valuable feature that allows the dynamic simulation of fish proximate composition. For the aquaculture industry it represents a trade-off between detailed process simulation and feasibility of model implementation, namely regarding data gathering on an operational setting. The EP model is targeted to simulate fish production in commercial farms. Farm data for feed intake, feed composition (energy and protein content), temperature over time and the initial fish body weight are the only required data to run the model. Furthermore, apparent digestibility coefficient (ADC) values of the feed used in the farm must be known or else ADC values of feeds with similar composition can be used. The EP model implementation is illustrated for the gilthead seabream (Sparus aurata) based on published experimental data. The model was validated (r = 0.997, p < 0.05, n = 12) using a published experimental data set for gilthead seabream reared in a range of temperatures that reproduce the conditions in most countries producing this species. For the entire growth period (488 days) the estimated mean absolute error (MAE) is 8.8 g.fish−1 and the mean absolute percentage error (MAPE) is 8.3%. Simulation of fish growth in real operational conditions is evaluated with three datasets from a commercial farm that operates in earthen ponds with temperatures ranging between 12.6 °C and 24.8 °C. Overall the model outputs match well with the production data in the 3 batches. Initial weight ranged between 2.8 g and 3.7 g. The deviation between the data and simulated final weights is below 15 g, for a final weight around 435 g. The maximum absolute error is 21.1 g per fish (MAE) and in percentage 8.3% (MAPE). 相似文献
6.
Three stochastic models were used to describe the growth of Heterodontus portusjacksoni off eastern Victoria, Australia. The models are based on a reparametrization of the von Bertalanffy growth model to take account of length-at-age heterogeneity, and incorporate random variation of the von Bertalanffy growth coefficient (k), using three different probability distribution functions (pdfs): Weibull, gamma and log-normal. They were fitted to the lengths of 179 specimens (79 females and 100 males), and associated age estimates obtained by counting growth bands in the inner trunk dentine layer of the dorsal-fin spines. The species is relatively long-lived (maximum estimated age of 35 years for females and 28 years for males) and slow growing, but has rapid growth during the early stages of life. All the models provided similar growth parameters and length-at-age quantiles. However, Kullbac?s information mean indicated that the stochastic model assuming a log-normal distribution fitted the length-at-age data better for both females (L∞ = 1337, E(k) = 0.059, t0 = 5.294) and males (L∞ = 1125, E(k) = 0.075, t0 = 4.944) than the models assuming other distributions. The χ2 likelihood ratio test indicated that females and males grow differently. 相似文献
7.
《Fisheries Research》2006,82(2-3):229-235
Model selection based on information theory is a relatively new paradigm in biological sciences with several advantages over the classical approaches. The aim of the present study was to apply information theory in the area of modelling fish growth and to show how model selection uncertainty may be taken into account when estimating growth parameters. The methodology was applied for length–age data of four species of fish, taken from the literature. Five-candidate models were fitted to each dataset: von Bertalanffy growth model (VBGM), generalized VBGM, Gompertz growth model, Schnute–Richards growth model, and logistic. In each case, the ‘best’ model was selected by minimizing the small-sample, bias-corrected form of the Akaike information criterion (AIC). To quantify the plausibility of each model, given the data and the set of five models, the ‘Akaike weight’ of each model was calculated. The average model was estimated for each case based on . Following a multi-model inference (MMI) approach, the model-averaged asymptotic length for each species was estimated, using all five models, by model-averaging estimations of L∞ and weighting the prediction of each model by . In the examples of this study, model selection uncertainty caused a magnification of the standard error of the asymptotic length of the best model (up to 3.9 times) and thus in all four cases estimating L∞ from just the best model would have caused overestimation of precision of the asymptotic length. The VBGM, when used for inference, without being the best model, could cause biased point estimation and false evaluation of precision. Model selection uncertainty should not be ignored even if VBGM is the best model. Multi-model inference by model-averaging, based on Akaike weights, is recommended for making robust parameter estimations and for dealing with uncertainty in model selection. 相似文献
8.
《Fisheries Research》1988,6(2):135-152
Estimates of von Bertalanffy growth model (VBGM) parameters K and L∞ were made for red drum (Sciaenops ocellatus), and black drum (Pogonias cromis), tagged and recaptured in Texas bays from November 1975 through June 1985. An annual temperature model was used to examine the growth model when periods of cold temperature were excluded. The best fit of the VBGM for red drum was based on time at large expressed in day-degrees with the coldest 60 days of the year excluded and yielded VBGM parameters estimates (± SE) of K = 0.422 (0.023) and L∞ = 918 (21) mm. Black drum data were best fitted with time at large expressed in days with the coldest 120 days of the year excluded and yielded VBGM parameters of K = 0.219 (0.027) and L∞ = 798 (42) mm. The exclusion of cold periods added to the body of evidence suggesting that scales and otoliths may be useful for ageing these species in the Gulf of Mexico. The source of the tag return (recreational fishermen, commercial fishermen, Texas Parks and Wildlife personnel) affected the parameter estimates. The pooled data, however, appeared to give the most reliable estimates. 相似文献
9.
Bayesian hierarchical models were developed to estimate the growth parameters of northern abalone, Haliotis kamtschatkana, using tag-recapture data with a mixture of single and multiple recaptures. Individual variability in the growth parameters L∞ and k of the von Bertalanffy model was incorporated in the analyses. The models developed fit the data well based on the Bayesian p-values. Variability in L∞ for individuals was high relative to the variability in L∞ for the population, and variability in k for individuals was about the same as the variability in k for the population. Simulations showed that estimates of the growth parameters were accurate (relative biases <5%), when variability in both L∞ and k or just in L∞ was accounted for. The “true” values of the parameters, L∞ and k, were contained in the estimated 95% credibility intervals in 90–94 out of 100 simulation runs on 100 simulated data sets. Overall, allowing for variability for both L∞ and k resulted in moderately more accurate estimates than allowing for just L∞. On the contrary, estimates were unreliable when variability in just k was considered. Using the WinBUGS software program, the calculation procedure was rather simple irrespective of which growth parameter was modeled with variability. 相似文献
10.
C.G. Askew 《Aquaculture (Amsterdam, Netherlands)》1978,14(2):91-104
A method is described for extrapolating the results from bivalve growth trials to cover either longer time periods or different size ranges. Examples of general size-related trends in growth and mortality rates of oysters, Ostrea edulis L. and Crassostrea gigas Thunberg are given, and their application to an economic model is described. This can be used to make projections of the likely sizes, numbers surviving and hence value of a stock, from the time of relaying until marketable size is reached. The results can be subjected to discounted cash flow analysis as a technique of project appraisal and in optimizing ongrowing schedules. The initial part of the method can be used separately in monitoring batch-to-batch or year-to-year differences in growth performance. 相似文献
11.
Marine macroalgae become increasingly important as a regenerative source of biomass for the production of food, pharmaceuticals, cosmetics and energy. An increasing and environmentally sound utilization of algae requires a closed, land-based cultivation, not limited to coastal or offshore areas. Within this study, segmental and ring-shaped cultivation vessels were developed and compared to tumble cultivation in a circular tank. The development of these innovative approaches also considered economic efficiency, adaptability, handling and reliability. The growth rates achieved by cultivating the red algae P. palmata and C. crispus and the green alga U. lactuca over a test period of 7 d were used to evaluate these experimental models. Mean growth rates of P. palmata and C. crispus in the ring-shaped cultivation model were slightly decreased whereas growth rate of U. lactuca was similar or increased compared to tank cultivated algae. The developed ring-shaped cultivation system distinctly lowered variable costs by reducing the necessary volume of cultivation medium. An increased control of the cultivation process was achieved by separating the supply of CO2 and nutrients, and the temperature control from agitation. 相似文献
12.
The design, construction and operation of a 100 m2 rectangular plastic-covered culture system for green algae (chlorella, scenedesmus) is described. A simple simulation model which predicts water temperature with an accuracy acceptable for estimating algal growth rate has been developed. Although simulated and measured observations showed significant statistical agreement, the model tends to underestimate daily maximum temperature and overestimate daily minimum temperature. The model can be readily adapated for usage in other parts of the world. 相似文献
13.
《Fisheries Research》2007,83(1-3):186-193
Large-scale environmental variation may drive the recruitment dynamics of estuarine-dependent fishes. High physiological tolerance allows estuarine-dependent species to take advantage of productive habitats; but abiotic variability can have a strong bearing on early growth and recruitment dynamics. Using spot (Leiostomus xanthurus) as a model estuarine-dependent species, we employed a multifaceted approach to examine abiotic influence on early growth by integrating data from a controlled growth experiment, continuous records of field conditions, and otolith growth records from the field. We asked whether fluctuation in early growth was controlled by the two primary abiotic variables, water temperature and salinity. Fluctuation in field growth was compared with expected fluctuation derived from laboratory growth parameters and abiotic variation experienced by juvenile spot in the field. Fluctuation in expected daily growth cross-correlated significantly with actual growth inferred from otolith microstructure over a 76 day field-growth period (r = 0.363; P < 0.001); however, the relationship was not strong enough to predict growth fluctuation. Moreover, high individual variability in inferred growth points to the importance of other abiotic and biotic variables. 相似文献
14.
《Aquaculture (Amsterdam, Netherlands)》2007,262(2-4):281-288
Two growth trials were completed on post-metamorphosed Atlantic cod (Gadus morhua) for a period of four weeks to determine the optimal temperature for best growth and feed efficiency. The same experiment was repeated twice under similar conditions to determine the effect of four temperature regimes (10, 12, 14 and 16 °C) on randomly selected juvenile cod with an initial weight ranging from 0.34 to 0.51 g. Post-metamorphosed cod grown at 14 and 16 °C were significantly larger at the end of the experiments than the fish grown at 10 or 12 °C, with specific growth rates following a similar trend (p < 0.05). Fish held at 16 °C utilized feed less efficiently than those held at the lower temperatures in experiment II and the highest feed efficiency was observed in fish held at 10 °C (p < 0.05). The results of the feed efficiency and the maximum growth per degree (dG / dTmax) in experiment II suggest that the feed efficiency was likely maximized at a lower temperature than those used in this study. By using data collected from sub-samples of fish in experiment II, maximum growth (Gmax) was estimated at 14.5 °C using a growth temperature model. Cannibalism was a problem in the first experiment but was greatly reduced in experiment II by feeding a larger size feed pellet (2 mm). 相似文献
15.
Small abalone Haliotis diversicolor (Reeve, 1846) is one of the smallest commercial abalone in the world. The successful application of artificial propagation and mass seed production techniques since the 1980s have resulted in the establishment of well-developed culture systems for small abalone in Taiwan. In the study reported here, we estimated the growth of a population of small abalone after a decade in a closed culture system and its growth characteristics with those of wild populations reported in previous studies. The von Bertalanffy growth equations of the shell length (L) and body weight (W) of cultured abalone were L t = 71.73 (1 ? e?0.84 (t?0.16)) and W t = 47.70 (1 ? e?0.84 (t?0.16))3.180, respectively. The instantaneous rate of change for weight had an inflection point at the age of 1.54 years, indicating that cultured abalones reach their apex of body growth around this age. Compared with the wild populations, the cultured population exhibits a significantly smaller maximal shell length (L ∞) and a significantly larger growth coefficient (k). Based on our results, it appears that the artificial culture of generations of small albalone for one decade or more in a closed system could be one of the major factors causing the observed minimization of size in the cultured abalone; this may be an adaptation in which growth is traded off for the larger k. 相似文献
16.
《水生生物资源》1998,11(5):315-324
An adaptation of the von Bertalanffy growth model is formulated to describe the phenotypic plasticity of fish somatic growth in relation to trophic conditions. The model is developed for the North sea Downs herring (Clupea harengus). It suggests that annual growth variability during 1974–1990 was mainly due to the combined effects of herring abundance and wind-induced turbulence (coincident with the spring stratification of the water column). Springtime turbulences cause reduced and delayed planktonic blooms preceding the annual foraging period of Downs herring. The negative relation observed between herring abundance and growth is hypothesized to be due to intra-specific competition for trophic resources. Incorporated into the calculation of yield per recruit, the established growth model provides slightly more optimistic diagnoses while dropping the classic assumption of constant weight at age. 相似文献
17.
Nabila F. Bishara 《Aquaculture (Amsterdam, Netherlands)》1976,8(4):337-349
Some aspects of the biometrics of Metapenaeus stebbingi, M. monoceros and Penaeus trisulcatus in the brackishwater Lake Manzalah are studied.M. stebbingi dominated the catch all over the lake from December 1966 to June 1967 followed by M. monoceros. The lowest percentage was that of P. trisulcatus which dominated the catch in the northeastern and western parts of the lake in the period September–December. M. monoceros dominated the catch in the northwestern area in the same period. The relation of this distribution to the nature of the lake bottom, chemical composition of the sediment and salinity variations are discussed.Age and growth studies showed that P. trisulcatus has an average monthly growth of 10 mm, and that the fishery is supported by the 0-year class. For M. monoceros an approximate growth of 5 mm/month was observed and it was concluded that the 2-year age group supported the fishery of this species.For M. stebbingi an approximate growth rate of 2–4 mm/month was observed and it was concluded that the I+ and II+ age groups constitute the catch.The growth studies show that P. trisulcatus and M. monoceros spawn during spring, while the peak of the spawning season for M. stebbingi is in the autumn. A close relationship was found between the seasonal variations in the rate of increase of prawn weight and the spawning season.The study included the distribution of the different species and length groups in the different parts of the lake. 相似文献
18.
《Aquaculture (Amsterdam, Netherlands)》1987,66(2):181-196
The growth of two species of Cichlidae, the African Oreochromis niloticus and the Central American Cichlasoma melanurum, fed with three different diets (100% pellets, 50% pellets and 50% Azolla, 100% Azolla) was compared. The growth performances of O. niloticus (G=2.3) fed only with pellets were higher than those of C. melanurum (G=0.9). With the mixed diet (50% pellets and 50% Azolla) growth was reduced for both species but this reduction was proportionally lower with C. melanurum. The fish fed exclusively with Azolla showed negative growth but fish weight loss was least for C. melanurum.Comparison of the chemical composition of the two fish species reveals significant differences. Generally moisture is lower for C. melanurum and lipid concentration is higher for this species with all three diets. Fed with Azolla, both species have a higher moisture and lower lipid concentration. Crude protein concentration (±15%) is very similar for both species regardless of diet.In conclusion, for intensive fish culture based on commercial pellets, the African species O. niloticus performs better than the American C. melanurum. On the other hand, the use of Azolla as feed for these fish does not seem very satisfactory but experiments should be conducted with typical herbivorous Cichlidae which may be able to utilize this fern in agro-piscicultural ecosystems. 相似文献
19.
The dietary value of dried, commercial Chlorella was compared with that of living marine Chlorella, and yeast, in relation to growth of the rotifer Brachionus plicatilis raised individually and by batch culture methods.A concentration of 50 μg/ml of dried Chlorella powder is near an optimal density for rotifer growth. The dried material in suspension is less effective for growth than living marine Chlorella, although it is much more effective than a suspension of yeast at the same density (50 μg/ml).In batch culture (12-l glass vessel), the rotifers grew from an initial inoculation of 13.2 individuals/ml to a density of 434 individuals/ml by the 16th day. About 107 rotifers could be removed from one batch culture in five harvests in the 41-day experimental period.The results indicate that dried Chlorella powder is an effective food for the rotifer Brachionus plicatilis. 相似文献
20.
The effects of temperature and food ration on the growth of juvenile loggerhead turtle, Caretta caretta L. were examined in relation to body weight under controlled conditions in the laboratory. With increasing food ration there was increasing growth rate. The best daily growth rate at 20°C water temperature was 1.87%. Basal metabolism was reached at a daily feed rate of 1.01% body weight at 20.5°C derived from a formula for growth, namely g = Af ? B where g = 0.62f ? 0.63. 相似文献