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961.
Renata Pietrzak-Fiećko Zdzisław Zakęś Mirosław Szczepkowski 《Journal Of Aquatic Food Product Technology》2017,26(10):1303-1311
The aim of the present study was to investigate the effect of thermal treatment methods, such as microwave cooking, steaming, and shallow pan-frying on fatty acids composition in northern pike fillets. All methods of thermal treatment increased fat content in the fillets. Microwave cooking decreased the proportion of saturated fatty acids and increased the proportion of total, n-3, and n-6 polyunsaturated fatty acids as compared with fresh fillets. Steam cooking did not affect the proportion of saturated, monounsaturated, and polyunsaturated fatty acids, whereas pan-frying significantly increased the proportion of monounsaturated and n-6 polyunsaturated fatty acids. All cooked fillets, regardless of the thermal treatment used, had acceptable n–6/n–3 ratio; however, microwave cooking enabled fish products to obtain more beneficial n-6/n-3 ratio than frying. Due to high polyunsaturated fatty acids content and low n-6/n-3 ratio, microwave cooking may be recommended for preparing wild pike fillets in households. 相似文献
962.
Ariane Furtado de Lima Maristela Cavicchioli Makrakis Fernanda Freitas Andrade Elaine Antoniassi Luiz Kashiwaqui Michele de Faveri Gimenes Sergio Makrakis 《Aquaculture Research》2017,48(4):1618-1628
The feeding selectivity of laboratory‐reared larvae of Rhamdia voulezi was assessed to investigate the preferred preys in early life stages. Three experiments were conducted at different larval development stages, starting soon after the absorption of the yolk sac (on fourth day after hatching – DAH), using zooplankton from fish ponds as food. Differences were detected in the patterns of prey selection among development stages. At first, the larvae prefer small preys, such as rotifers and cladocerans. Later, when they are more developed, they prefer to feed on large preys, such as copepods. On the fourth DAH, larvae in the pre‐flexion and initial flexion stage strongly selected rotifers and cladocerans (Diaphanosoma spinulosum, D. brevireme, Moina sp., M. micrura and M. minuta). At the other stages, cladocerans continued to be strongly selected. However, on the eighth DAH, larvae in flexion stage selected less strongly copepods Argyrodiaptomus azevedoi, Metacyclops mendocinus and Termocyclops decipiens. On the tenth DAH, larvae in postflexion stage selected more strongly copepods Argyrodiaptomus furcatus, Notodiaptomus cf. spinuliferus and M. mendocinus. As larvae grow, they tend to specialize in feeding of a particular prey. Prey selection of R. voulezi larvae was based both on species and zooplankton size. The size of the zooplankton ingested was related to the mouth gape size of larvae. 相似文献
963.
Renata M dos Santos Giseli S Rocha Odete Rocha & Maria José Santos Wisniewski 《Aquaculture Research》2009,40(7):753-761
The aim of this study was to examine the influence of the net cage system of fish culture on the composition, abundance and diversity of the zooplankton community. Comparisons were made between three collection points located near a group of 30 net cages, with individual volumes of approximately 4 m3 , containing newly hatched, young and adult Nile tilapia, positioned in an arm of the Furnas hydroelectric reservoir; point 1 was in the limnetic region and points 2 and 3 were upstream and downstream of the cages, respectively, near the bank. The sampling was carried out at all three points from July to December, 2005. The composition of the zooplankton community differed among the points analysed. The lowest diversity was recorded at point 1. Point 2, upstream of the cages, was characterized by greater species richness and higher density of organisms pertaining to the Rotifera group. The results of the study suggest that variations in the composition and abundance of Rotifera and Cladocera are a consequence of the impact of net cage fish culture, although the magnitude of the variations is small. 相似文献
964.
965.
Thais Grassi Gericó Renan Francisco Rimoldi Tavanti Jéssica Pacheco de Lima Rodolfo Pires Ribeiro Leandro Cesar Cusim dos Santos Marcio Souza da Silva 《Journal of plant nutrition》2020,43(12):1907-1922
AbstractThe objective of this study was to evaluate the effects of cobalt (Co) and molybdenum (Mo) doses in the treatment of seeds on the biosynthesis of nitrogen compounds, photosynthetic pigments, sugars, and production of peanut plants. The doses of Co and Mo used were 0, 2, 3, and 4?mL kg?1 seed, which were applied immediately before sowing. Seeds treated with Co and Mo at a dose of 4?mL kg?1 yielded peanut plants with higher concentrations of photosynthetic pigments, carotenoids, and sucrose in leaves. Application of Co and Mo doses also increased biological nitrogen fixation by increasing the concentration of allantoic acid, nitrate, ammonia, and amino acids in leaves. The concentration of total amino acids corresponded to most of the nitrogen compounds (on average 50%), followed by the concentrations of nitrate (35%), ammonia (11%), allantoic acid (7%), and allantoin (0.2%). Application of 4?mL kg?1 increased the production of total amino acids compared with the control treatment. Pod yield was not affected by the Co and Mo doses; however, treatment of peanut seeds with 4?mL kg?1 was the most viable alternative for increased production of primary metabolism compounds, nitrogen forms, and photosynthetic pigments in peanut plants. This study provides important information regarding the role of Co and Mo in the biological nitrogen fixation of peanut plants. Future experiments should be conducted using a dose of 4?mL kg?1 with different genotypes to verify the potential for increasing peanut yield. 相似文献
966.
Auren Benk Soso Leonardo José Gil Barcellos Maria José Ranzani‐Paiva Luiz Carlos Kreutz Rosmari Mezzalira Quevedo Marina Lima Leonardo Bolognesida Silva Filipe Ritter Alexandra Calliari Bedin Jovani Antônio Finco 《Journal of the World Aquaculture Society》2008,39(6):835-841
Abstract.— A stressful environment induces cortisol that might affect fish breeding and reproduction. In the present work, which aimed to mimic aquacultural conditions of the jundia (Rhamdia quelen) hatcheries in southern South America, females were submitted to normal or stressful handling and the effects of cortisol on serum levels of 17β‐estradiol (E2) and testosterone (T) were determined. In addition, the effect of stress on reproductive parameters such as eggs and swim‐up fry production was also measured. Eight females from a group submitted to stressful handling (SH) conditions and eight females from a group with normal handling (NH) conditions were captured for blood sampling at D 0 and at D 1, 10, 20, 30, and 40 of the experiment. A typical cortisol response was observed in the SH females group in that they presented higher cortisol level in contrast to the NH female group, in all days sampled, except at D 0. In the 10th and 20th d, the E2 levels were lower in SH females, but cortisol levels were higher, suggesting an effect of cortisol on E2 production and/or release. Stressful handling appeared to affect both the number and the quality of the gametes because a lower number of oocytes was stripped from SH females, and from SH fertilized eggs, a lower number of viable swim‐up fry was obtained to be transferred to earthen larviculture ponds. Taken together, the results indicated that stressful handling of broodstock impairs R. quelen reproduction. 相似文献
967.
Ana Patrícia Souza De Lima Andréa Carla Lira Dos Santos Hozana Leite Dantas Manoel Adrião Gomes Filho Rodrigo Maggioni Maria Raquel Moura Coimbra 《Aquaculture Research》2008,39(13):1461-1466
Loss of genetic variability can be detrimental to a population's survival traits and fitness. These effects are likely to be maximized in shrimp closed broodstock rearing systems where post‐larvae are often produced from crosses of breeders collected from an associated grow‐out farm after mass selection. Longtime broodstock management in closed systems is also expected to lead to reduction in or even complete eradication of genetic variability. The present work aimed at monitoring the genetic variability of a Litopenaeus vannamei hatchery in the state of Pernambuco (Brazil), during three successive replacements, using microsatellite markers. No significant genetic diversity losses have been observed through the values of mean heterozygosity (Ho=0.460 and He=0.660 in the first sample; Ho=0.420 and He=0.620 in the second sample; and Ho=0.600 and He=0.660 in the third sample). However, some alleles appear to have been lost after three replacements. The diversity level was considered to be high and is comparable to those reported for wild populations, suggesting that the original imported founder stock of Brazilian L. vannamei is likely to have had a high genetic diversity, possibly due to multiple origins. 相似文献
968.
Siwaporn Siltecho Nopmanee Suvannang Juthamard Kaiphoem Erika Medeiros José Romualdo de Sousa Lima Nattaporn Prakongkep Robert Gilkes Claude Hammecker 《Soil Use and Management》2022,38(2):1293-1306
Pradoo wood biochar has been tested in order to explore sustainable solutions to the development of agriculture on poor sandy soils in marginal areas in Northeast Thailand. Some basic physicochemical properties of biochar, for example pore size distribution, cation exchange capacity (CEC), specific surface area (SSA), and water and nutrient adsorption, were determined and compared to soil properties in order to determine appropriate biochar application to soil. Pradoo wood biochar showed important adsorption properties with high SSA, CEC and nutrient adsorption. The water retention properties were also improved on the dry end of the water retention curve. Phosphorous and ammonium adsorption–desorption isotherms were established and their respective affinity for the biochar surface was quantified, by the means of a retention index and thermodynamical parameters. We found that despite excellent retention properties, biochar needs to be added in large amounts (between 10 and 70 kg m−2) to soil to be able to modify noticeably the resulting soil properties. 相似文献
969.
da Silva Reginaldo Barboza Iori Piero Tavares Rose Luiza Moraes de Souza Zigomar Menezes de Lima Camila Cassante de Melo Silva Francisca Alcivânia de Souza Bento Marília 《Precision Agriculture》2022,23(3):984-1007
Precision Agriculture - Changes in land use in riverside ecosystems added to the flood and ebb regimes of rivers modify the spatial variability of the physical–mechanical attributes of soil,... 相似文献