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731.
Maria Luísa Dâmaso-Rodrigues Pedro Pousão-Ferreira Laura Ribeiro Joana Coutinho Narcisa M. Bandarra Paulo J. Gavaia Luís Narciso Sofia Morais 《Aquaculture International》2010,18(5):741-757
Despite the large progress obtained in recent years, Senegalese sole (Solea senegalensis) production of high quality juveniles is still a bottleneck. This paper examines the effect of larval and post-larval lipid
nutrition on juvenile performance and quality. Four dietary treatments were tested: A—enriched Artemia spp. (EA); B—non-enriched Artemia spp. (NEA); C—EA during the pelagic larval period and NEA after larval settlement; D—50% EA and 50% NEA. Juvenile fatty acid
profile at 60 days after hatching (DAH) clearly reflected the larval and post-larval diet composition. Feeding sole larvae
on NEA (poor in lipids and essential fatty acids-EFA) had a negative effect, reducing growth (total length and dry weight)
after 30 DAH and decreasing digestive enzyme activity at the end of the rearing period (60 DAH). However, relatively good
performance compared to the EFA-richest treatment (A) was obtained when larvae were fed 50% EA and 50% NEA (D) or even EA
only during the pelagic larval period followed by NEA after larval settlement (C). Malpigmentation was not affected by the
dietary regimes and its incidence was very low. However, skeletal deformities were prevalent, particularly in the caudal complex,
independently of diet. The results confirm that Senegalese sole appear to have lower larval EFA requirements than most cultured
marine species and potentially even lower requirements during the post-larval stage. The importance of studying the impact
of early nutrition on later juvenile stages was clearly highlighted in this study. 相似文献
732.
Albino Luciani Gonçalves Leal Patrícia Fernandes de Castro João Paulo Viana de Lima Eudes de Souza Correia Ranilson de Souza Bezerra 《Aquaculture International》2010,18(4):635-646
A 45-day feeding trial was carried out to evaluate the use of shrimp protein hydrolysate (SPH) in diets for Oreochromis niloticus, L. SPH was included in isonitrogenous diets replacing fish meal protein by 0, 5, 10, and 20% and offered to Nile tilapia juveniles (1.7 ± 0.4 g) stocked in 40-L glass aquaria. The inclusion of SPH produced no significant differences (P ≥ 0.05) in final weight, survival, weight gain, average daily gain, specific growth rate, feed conversion ratio, protein efficiency ratio, or apparent net protein utilization. The inclusion of SPH Nile tilapia diets significantly affected (P < 0.05) the final fish body composition. Protein and ash contents decreased and fat content increased slightly with the increase in SPH. This study has demonstrated that SPH is a promising protein feedstuff and could account for as much as 6% of Nile tilapia diets with no adverse effects on growth and nutrient utilization. 相似文献
733.
Luis E. C. Conceição Cláudia Aragão Nadège Richard Sofia Engrola Paulo Gavaia Sara Mira Jorge Dias 《Fish physiology and biochemistry》2010,36(1):1-16
Major gaps in knowledge on fish larval nutritional requirements still remain. Small larval size, and difficulties in acceptance
of inert microdiets, makes progress slow and cumbersome. This lack of knowledge in fish larval nutritional requirements is
one of the causes of high mortalities and quality problems commonly observed in marine larviculture. In recent years, several
novel methodologies have contributed to significant progress in fish larval nutrition. Others are emerging and are likely
to bring further insight into larval nutritional physiology and requirements. This paper reviews a range of new tools and
some examples of their present use, as well as potential future applications in the study of fish larvae nutrition. Tube-feeding
and incorporation into Artemia of 14C-amino acids and lipids allowed studying Artemia intake, digestion and absorption and utilisation of these nutrients. Diet selection by fish larvae has been studied with
diets containing different natural stable isotope signatures or diets where different rare metal oxides were added. Mechanistic
modelling has been used as a tool to integrate existing knowledge and reveal gaps, and also to better understand results obtained
in tracer studies. Population genomics may assist in assessing genotype effects on nutritional requirements, by using progeny
testing in fish reared in the same tanks, and also in identifying QTLs for larval stages. Functional genomics and proteomics
enable the study of gene and protein expression under various dietary conditions, and thereby identify the metabolic pathways
which are affected by a given nutrient. Promising results were obtained using the metabolic programming concept in early life
to facilitate utilisation of certain nutrients at later stages. All together, these methodologies have made decisive contributions,
and are expected to do even more in the near future, to build a knowledge basis for development of optimised diets and feeding
regimes for different species of larval fish. 相似文献
734.
Tatiane Mary Gogola Pitgoras Augusto Piana Pedro Rogrio Leandro da Silva Dhyego Amilton Topan Paulo Vanderlei Sanches 《Ecology of Freshwater Fish》2022,31(1):154-163
The reproductive activity of the fish assemblage in a large Neotropical reservoir was evaluated by surveying the occurrence of ichthyoplankton in response to spatial and temporal variation in environmental factors. Fish reproduction was investigated by capturing larvae along representative spatial gradients in the main body (longitudinal) and arms (lateral) of the reservoir. After identification, the captured larvae were classified into different groups according to the functional traits of their parental stock. Sampling occurred monthly at night from October to March over five reproductive periods between 2009 and 2016, using conical-cylindrical plankton nets with flowmeter. Water samples were taken simultaneously allowing the measurement of environmental factors related to reproductive activity. The relationship between the environmental factors and the functional traits was assessed using RLQ and fourth-corner analyses. An evaluation of 51,995 larvae revealed there was greater larval abundance in the lacustrine and transition zones of both longitudinal and lateral gradients. Occurrences often correlated with temporal instead of spatial gradients. Higher rainfall correlated with abundances of detritivorous and migratory species. Higher water levels correlated with higher abundances of non-native species, species without parental care, with external fecundation, and partial spawning. Dry periods, with lower water and higher dissolved oxygen, correlated with higher abundances of insectivores and sedentary species. Although the presence of a dam-free stretch of river upstream of the reservoir had a positive influence on fish larvae in the fluvial zone, the results did not show differentiation along either gradient. Thus, the composition of the functional groups of fish species that reproduce in the Itaipu Reservoir appears to be predominantly influenced by the temporal variation in environmental factors rather than the formation of spatial gradients. 相似文献
735.
Lenir Fátima Gotz Nerilde Favaretto Gabriel Barth Paulo Sergio Pavinato Volnei Pauletti 《Soil Use and Management》2023,39(1):606-617
The benefits of manure as a source of nutrients for plants and to improve soil quality are well-known. Monitoring of manure application is needed if environmental issues are to be prevented. In particular, the availability and accumulation of phosphorus (P) has to be subject to rigorous monitoring. This study aims to both evaluate the efficacy of the resin method in extracting inorganic labile P in soils under the long-term application of dairy liquid manure (DLM), and verify the influence of DLM on the recovery of applied P and soil legacy P. To realize our objectives, two long-term field experiments were established under a no-tillage system with annual DLM application on sandy clay loam (sandy Oxisol) and clayey (clayey Oxisol) soils. Treatment consisted of DLM applications (0, 60, 120, 180 m3 ha−1 year−1), independent of mineral fertilizer. Soil samples were taken from the 0–5, 5–10 and 10–15 cm layers after 10 years from the beginning of the trial. A single extraction with resin underestimated inorganic labile P; however, successive extractions were able to take up 43% and 26% of the total P in sandy and clayey Oxisols, respectively, whereas in a single extraction the take-up was 17% and 8% from the same soils, respectively. The resin method was more effective in extracting P from the sandy Oxisol. Thus, when interpreting soil P contents for fertilizer planning, the soil texture should be taken into account. DLM application decreased P recovered from applied P, ranging from 54% to 83% (sandy), and 43% to 67% (clayey), and substantially increased soil legacy P. 相似文献