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441.
Samet Can Söylemez Keisuke Murakami Carlos Augusto Strüssmann Masashi Yokota Seiichi Watanabe 《Fisheries Science》2010,76(3):437-444
This study examined the ability of late stage (instar XXVI) Japanese spiny lobster Panulirus japonicus phyllosoma larvae to uptake seven l-type amino acids (AAs; aspartic acid, Asp; threonine, Thr; glutamic acid, Glu; glycine, Gly; alanine, Ala; valine, Val; and
methionine, Met) from the rearing medium. The time course uptake during incubation for 5 h in solutions containing 1, 2, 5,
10, or 20 μM of each AA was determined using high performance liquid chromatography. There was considerable individual variation
in uptake rates and even occasional release of AAs, but larvae showed net uptakes of all seven AAs. Two polar acidic AAs (Glu
and Asp) were readily taken up whereas neutral AAs, including three considered as essential for crustaceans (Val, Met, and
Thr), had lower uptake rates. Transient releases of AAs by the larvae were common for the AAs with the lowest uptake rates
at 1–2 h of incubation. Uptake rates increased with increasing AA concentration but less so for those taken up in larger amounts.
Larvae took up AAs to a total of 16.4 μmol/g/h for incubation in the 20 μM solution. The ability to uptake nutrients directly
from the medium may be important for the well-being of the larvae. 相似文献
442.
Carla Patricia Bejo Wolkers Mônica Serra Augusto Barbosa Júnior Elisabeth Criscuolo Urbinati 《Fish physiology and biochemistry》2017,43(3):755-759
Fluoxetine (FLX) is a selective serotonin (5-HT) reuptake inhibitor known for its effects modifying aggressiveness, personality traits, and anxiety-like behaviors. The aim of the present study was to evaluate the influence of the acute treatment, by immersion, with FLX on aggressive behavior of resident Brycon amazonicus fish. Fish pretreated with FLX presented an increase in aggressiveness, evidenced by the increase on the number of bites and chases against the intruder and a decrease in latency for the first attack, when compared to control fish. Together with previous studies, these results show the complexity of the neural modulation of the aggressive behavior in fish by 5-HTergic system. 相似文献
443.
Letícia de Abreu Faria Gustavo Rodrigues Bardella Thiago Augusto de Moura Fernanda Latanze Mendes Godofredo Cesar Vitti 《Communications in Soil Science and Plant Analysis》2016,47(6):769-774
High losses of nitrogen (N) by volatilization of ammonia from urea applied in Eucalyptus are expected due to the influence of plant residues on the soil surface. The study evaluated the N losses by volatilization of ammonia from urea coated with Thiophosphate N-(n-butil) triamide (NBPT) applied in soil with eucalyptus residues in surface under moisture treatments: fertilization in dry soil without irrigation; fertilization in dry soil with posterior irrigation depth (3 mm); fertilization in moist soil without irrigation and fertilization in moist soil with irrigation depth (3 mm). NBPT is a potential inhibitor of urease. Urea with NBPT shows lower losses by volatilization of ammonia when it is applied in dry soil; however in soil conditions of high moisture the losses as well as inhibitor effect of the NBPT are lower. The inhibitor effect of NBPT is reduced over time when it is subjected to moisture conditions. 相似文献
444.
Carlos Augusto Prata Gaona Fabiane da Paz Serra Plínio Schmidt Furtado Luis Henrique Poersch Wilson WasieleskyJr. 《Aquaculture International》2016,24(5):1263-1275
Different water flows for solids removal in the Litopenaeus vannamei BFT system were evaluated. One control (no solids removal) and two treatments using different water flows, high (3945 L h?1—HF) and low (1750 L h?1—LF), were used with no water replenishment after each process, and the total dry weight of the solids was measured. L. vannamei (0.18 ± 0.06 g; 350 individuals m?2) were stocked in 35-m?3 tanks. For 17 weeks, the physical and chemical parameters were maintained within the recommended. To keep the total suspended solids concentrations at approximately 500–600 mg L?1, clarifying was performed. The average water volume flowed by clarifiers was significantly different (p < 0.05) between HF (205 ± 34 m3) and LF (114 ± 24 m3). There was a significant decrease (p < 0.05) in the final tank volume in HF (28.09 ± 0.92 m3) and LF (28.62 ± 1.38 m3) due to the clarifying. Before clarifying (initial sample) and at the end of experiment (final sample) were not significantly different (p > 0.05) for crude protein, moisture or ash. The crude lipid of the LF in the final period was significantly lower (p < 0.05) compared to others in both periods. The survival, productivity and food conversion ratio were significantly better (p < 0.05) in the HF and LF treatments compared to those of the control. The best shrimp performance was obtained with solids removal. The lower flow in the clarifier facilitated particle settling, allowing adjustment of the flow. 相似文献
445.
Raphael Santos Craig A. Radford Joseph Poupin Christophe Brié Suzanne C. Mills René Galzin David Lecchini 《Fisheries Science》2012,78(1):75-80
The post-larval supply of two crustacean taxa (Brachyura and Stomatopoda) was monitored using one crest net over three lunar
months at Rangiroa Atoll, French Polynesia. We captured a total of 37,068 brachyuran and 12,697 stomatopod post-larvae during
the study. Post-larval supply was higher during the warm season (February–April) than during the cold season (June–July) for
both Brachyura (warm season: 85% of total post-larval supply) and Stomatopoda (warm season: 92%). Moreover, the pulse of the
brachyuran post-larval supply occurred predominantly around the last quarter, while the pulse of stomatopods occurred predominantly
around the new moon. However, for both taxa, the post-larval supply was lowest around the full moon and the first quarter.
Overall, our monitoring highlighted that the post-larval supply of Brachyura and Stomatopoda was modulated by seasons and
lunar phases at Rangiroa. 相似文献
446.
Emanuell Felipe Silva Marcelo Augusto Soares Nathalia Ferreira Calazans Joana Lyra Vogeley Bruna Cáritas do Valle Roberta Soares Silvio Peixoto 《Aquaculture Research》2012,44(1):13-21
The effect of the addition of Bacillus probiotic during larvae and postlarvae culture of the white shrimp Litopenaeus vannamei was examined in three separate experiments: (I) Nauplius4‐5 to Zoea3, which were exposed to probiotic in the water (Pw), only in the microalgae (Pm), in the water and microalgae (Pwm) and a control with no probiotic (C); (II) Mysis1 to Mysis3, which were exposed to probiotic in the water (Pw), only in Artemia (Pa), in the water and Artemia (Pwa) and a control (C); (III) PL1 to PL10, which were exposed to similar treatments for mysis experiment. The use of probiotic Bacillus spp. resulted in an increase in the survival and growth of zoea and mysis phases, especially when the probiotic was added only in the water. For postlarvae, the use of the probiotic had no influence on the zootechnical parameters, however, there was a reduction in the count of presumptive Vibrio both for water and shrimp. 相似文献
447.
Leonardo Augusto Coelho Ribeiro Tiago Bresolin Guilherme Jordo de Magalhes Rosa Daniel Rume Casagrande Marina de Arruda Camargo Danes Joo Ricardo Rebouas Drea 《Journal of animal science》2021,99(9)
Wearable sensors have been explored as an alternative for real-time monitoring of cattle feeding behavior in grazing systems. To evaluate the performance of predictive models such as machine learning (ML) techniques, data cross-validation (CV) approaches are often employed. However, due to data dependencies and confounding effects, poorly performed validation strategies may significantly inflate the prediction quality. In this context, our objective was to evaluate the effect of different CV strategies on the prediction of grazing activities in cattle using wearable sensor (accelerometer) data and ML algorithms. Six Nellore bulls (average live weight of 345 ± 21 kg) had their behavior visually classified as grazing or not-grazing for a period of 15 d. Elastic Net Generalized Linear Model (GLM), Random Forest (RF), and Artificial Neural Network (ANN) were employed to predict grazing activity (grazing or not-grazing) using 3-axis accelerometer data. For each analytical method, three CV strategies were evaluated: holdout, leave-one-animal-out (LOAO), and leave-one-day-out (LODO). Algorithms were trained using similar dataset sizes (holdout: n = 57,862; LOAO: n = 56,786; LODO: n = 56,672). Overall, GLM delivered the worst prediction accuracy (53%) compared with the ML techniques (65% for both RF and ANN), and ANN performed slightly better than RF for LOAO (73%) and LODO (64%) across CV strategies. The holdout yielded the highest nominal accuracy values for all three ML approaches (GLM: 59%, RF: 76%, and ANN: 74%), followed by LODO (GLM: 49%, RF: 61%, and ANN: 63%) and LOAO (GLM: 52%, RF: 57%, and ANN: 57%). With a larger dataset (i.e., more animals and grazing management scenarios), it is expected that accuracy could be increased. Most importantly, the greater prediction accuracy observed for holdout CV may simply indicate a lack of data independence and the presence of carry-over effects from animals and grazing management. Our results suggest that generalizing predictive models to unknown (not used for training) animals or grazing management may incur poor prediction quality. The results highlight the need for using management knowledge to define the validation strategy that is closer to the real-life situation, i.e., the intended application of the predictive model. 相似文献
448.
Alex Augusto Gonçalves 《Journal Of Aquatic Food Product Technology》2013,22(2):210-229
ABSTRACTIn recent years, increasing attention has been focused on food safety, and in particular on the intervention methods to reduce and/or eliminate human pathogens from fresh products. Many research and industrial trials are underway to validate the use of ozone in the food industry as an alternative treatment to improve food safety. Notably, when ozone is applied to food surfaces, it leaves no residues since it decomposes quickly. Chemical and physical properties of ozone, its generation, and the antimicrobial power of ozone were explained as well as many advantages of ozone uses in the seafood industry. 相似文献
449.
Faruq Ahmed Yasuyuki Koike Carlos Augusto Strüssmann Seiichi Watanabe 《Aquaculture International》2013,21(5):969-986
Effect of stocking density was studied in three abalone species Haliotis discus discus (HDD), H. gigantea (HG), and H. madaka (HM) and their hybrids [HDD × HM, HM × HG and HG × HM, mother first] by rearing individually marked abalones for 217 days at low (22 % of available surface area; LD), medium (53 %; MD), and high (126 %; HD) densities. Feeding rate (FR) and feed conversion rate were observed by measuring the amount of feed ingested at an interval of 2–3 days. Reduction of growth rate with the increment of density was found in all three species [Specific growth rate in weight (G W ) HDD, LD: 0.121, MD: 0.093, HD: 0.069; HM: 0.12, 0.082, 0.061; HG: 0.254, 0.222, and 0.131] and the hybrids HDD × HM (0.18, 0.109, 0.108). The medium density produced the highest growth rates in HM × HG and HG × HM hybrids (0.284, 0.342, 0.28). A growth spurt was observed in all three species and hybrids in the last 44 days of rearing. FR varied from 0.72 to 7.97 % body weight and decreased with the increase in density in all species and hybrids. The results indicate differences in density thresholds for the three abalone species and their hybrids suggesting requirement of different aquaculture management strategies for them. 相似文献
450.
Menegat Alexander Bailly Geraldine C. Aponte Raphael Heinrich Gregor M. T. Sievernich Bernd Gerhards Roland 《植物病害和植物保护杂志》2016,123(4):145-153
Journal of Plant Diseases and Protection - Recently, the acetohydroxyacid synthase (AHAS) amino acid substitution Asp376Glu was detected in a Lolium perenne population originating in France. This... 相似文献