Growth performance and metabolic utilization of diets including starch,dextrin, maltose or glucose as carbohydrate source by gilthead sea bream (<Emphasis Type="Italic">Sparus aurata</Emphasis>) juveniles     

P. Enes  H. Peres  A. Couto  A. Oliva-Teles 《Fish physiology and biochemistry》2010,36(4):903-910

The effect of dietary carbohydrate complexity on growth, feed utilization and activity of selected key liver enzymes of intermediary metabolism were studied in gilthead sea bream juveniles. Four isonitrogenous (50% crude protein) and isolipidic (16% crude lipids) diets were formulated to contain 20% of pregelatinized maize starch, dextrin, maltose or glucose. Triplicate groups of fish (117 g initial weight) were fed each diet to near satiation during 6 weeks. No effect of dietary carbohydrate on growth was noticed. Feed efficiency was lower in fish fed the glucose diet than the maltose and dextrin diets. The lowest protein efficiency ratio was observed in fish fed the glucose diet. Six hours after feeding, glycemia was higher in fish fed the glucose diet than the maltose and starch diets. Liver glycogen content was unaffected by dietary carbohydrate complexity. Hepatic glucokinase (GK) activity was higher in fish fed the glucose and the maltose diets, while higher pyruvate kinase (PK) activity was recorded in fish fed the glucose diet than in fish fed the starch diet. Fructose-1,6-bisphosphatase (FBPase) and glucose-6-phosphate dehydrogenase (G6PD) activities were higher in fish fed the starch diet compared to dextrin and glucose diets. Data suggest that dietary glucose and maltose are more effective than complex carbohydrates in enhancing liver glycolytic activity. Dietary glucose also seems to be more effective than starch in depressing liver gluconeogenic and lipogenic activities. Overall, dietary maltose, dextrin or starch was better utilized than glucose as energy source by gilthead sea bream juveniles.  相似文献   

Operational oceanography applied to skipjack tuna (Katsuwonus pelamis) habitat monitoring and fishing in south‐western Atlantic     

Juliano Lauser Coletto  Marcelo Peres Pinho  Lauro Saint Pastous Madureira 《Fisheries Oceanography》2019,28(1):82-93

Skipjack tuna (Katsuwonus pelamis) ranks third among marine resources that sustain global fisheries. This study delimits the spatiotemporal habitat of the species in the south‐western Atlantic Ocean, based on operational oceanography. We used generalized additive models (GAMs) and catch data from six pole‐and‐line fishing vessels operating during 2014 and 2015 fishing seasons to assess the effect of environmental variables on catch. We also analysed Modis sensor images of sea surface temperature (SST) and surface chlorophyll‐α concentration (SCC) to describe fishing ground characteristics in time and space. Catch was positively related to thermocline depth (24–45 m), SST (22–24.5°C), SCC (0.08–0.14 mg/m³) and salinity (34.9–35.8). Through SST images, we identified that thermal fronts were the main surface feature associated with a higher probability to find skipjack. Also, we state that skipjack fishery is tightly related to shelf break because bottom topography drives the position of fronts in this area. Ocean colour fronts and plankton enrichment were important proxies, accessible through SCC, used to delineate skipjack fishing grounds. Catch per unit effort (CPUE) was higher towards summer (median 14 t/fishing day) due to the oceanographic characteristics of the southern region. High productivity in this sector of the Brazilian coast defines the main skipjack feeding areas and, as a consequence, the greatest abundance and availability for fishing.  相似文献   

Spatial variability of leaf macronutrient concentration and fruit production of an Arabica coffee plantation using two sampling densities     

Ferreira  Gabriel Fernandes Pinto  Lemos  Odair Lacerda  Soratto  Rogério Peres  Perdoná  Marcos José 《Precision Agriculture》2022,23(4):1473-1488

Precision Agriculture - The nutritional and productive attributes of Arabica coffee (Coffea arabica L.) can vary spatially within cultivated areas. Precision farming techniques applied to coffee...  相似文献   

Fine thermal structure of a coronal active region     

Reale F  Parenti S  Reeves KK  Weber M  Bobra MG  Barbera M  Kano R  Narukage N  Shimojo M  Sakao T  Peres G  Golub L 《Science (New York, N.Y.)》2007,318(5856):1582-1585

The determination of the fine thermal structure of the solar corona is fundamental to constraining the coronal heating mechanisms. The Hinode X-ray Telescope collected images of the solar corona in different passbands, thus providing temperature diagnostics through energy ratios. By combining different filters to optimize the signal-to-noise ratio, we observed a coronal active region in five filters, revealing a highly thermally structured corona: very fine structures in the core of the region and on a larger scale further away. We observed continuous thermal distribution along the coronal loops, as well as entangled structures, and variations of thermal structuring along the line of sight.  相似文献   

Forest area predicts all dimensions of small mammal and lizard diversity in Amazonian insular forest fragments     

Palmeirim  Ana Filipa  Farneda  Fábio Z.  Vieira  Marcus Vinícius  Peres  Carlos A. 《Landscape Ecology》2021,36(12):3401-3418

Landscape Ecology - Although hydropower development is one of the primary drivers of habitat loss and insular fragmentation, its impacts on species identity and their functional and phylogenetic...  相似文献   

Existing protected areas provide a poor safety-net for threatened Amazonian fish species     

Fernando C. P. Dagosta  Mário de Pinna  Carlos A. Peres  Victor A. Tagliacollo 《水产资源保护:海洋与淡水生态系统》2021,31(12):1167-1189

1. Freshwater ecosystems represent less than 0.01% of Earth's surface water but proportionately encompass the most species-rich environment on the planet, including nearly one-third of all vertebrate species. Even though inland continental waters are widely regarded as highly endangered ecosystems, their species assemblages are mostly ignored in conservation plans, largely because spatial patterns of freshwater species remain poorly understood. This is particularly severe throughout the Neotropics, most notably in the Amazon superbasin, where the sheer biotic diversity is coupled with a severe lack of biodiversity knowledge at several levels.
2. Spatial patterns of Neotropical freshwater fishes focusing mainly on the Amazon superbasin were investigated. First, Endemic Amazonian Fish Areas (EAFAs) representing central units for the conservation of continental fishes were delimited. Interpolated maps were then analysed using alternative methodologies to delimit spatial patterns of diversity and endemicity across the Amazon superbasin. Several biogeographical analyses used a comprehensive dataset of species and geographical coordinates of Amazonian fishes.
3. The results reveal well-defined spatial patterns of species richness and endemicity in the Amazonian fish fauna, showing that most protected areas are concentrated in a single bioregion (Amazon lowlands). Those areas are incongruent and insufficient to protect endemic and threatened species, which are mostly distributed in upland regions.
4. Effective conservation of the Amazonian fish fauna should include EAFAs within protected areas, especially those undergoing deforestation and hydropower development pressure and containing a high concentration of threatened species.
5. The following EAFAs should be considered as conservation priorities: Upper Araguaia, Upper Tocantins, Lower Teles Pires/Serra do Cachimbo, Chapada dos Parecis and Upper Marañon. These regions should be urgently protected to avert the loss of important trophic relationships and unique elements of the Amazonian fish fauna.

  相似文献   

FIRST REPORT OF GENUS Cryptosporidium IN CERVIDS SPECIES: Mazama americana,Mazama nana AND Blastocerus dichotomus     

Pires Teixeira  Weslen Fabricio  de Oliveira  Márcio Leite  de Faria Peres  Pedro Henrique  Miranda Oliveira  Bruno César  Nagata  Walter Bertequini  da Silva Vieira  Dielson  de Andrade Junior  Anassilton Moreira  Domingos Ferrari  Elis  Barbanti Duarte  José Maurício  Vasconcelos Meireles  Marcelo  Zanetti Lopes  Welber Daniel  Saraiva Bresciani  Katia Denise 《Veterinary research communications》2022,46(1):49-58

Veterinary Research Communications - We analyzed Cryptosporidium spp. in fecal samples of wild cervids (Ozotoceros bezoarticus, Blastocerus dichotomus, Mazama nana, Mazama americana, and Mazama...  相似文献   

Effects of crude protein and sodium intake on water turnover in cats fed extruded diets     

Caroline A. Garcia  Bruna A. Loureiro  Francine M. Peres  Camila Goloni  Ludmilla G. Di Santo  Fernanda S. Mendonça  Aulus C. Carciofi 《Journal of animal physiology and animal nutrition》2021,105(Z2):95-105

The comprehension of strategies to increase urine production may be important, especially in kibble diets to prevent urolithiasis in cats. The effects of increasing amounts of crude protein (CP) and sodium on the water turnover of cats were evaluated using the water balance (WB) method and the deuterium dilution technique. The study followed a randomized block design, with three blocks of eight cats, two cats per food type in each block, and six cats per food. Four extruded diets with different amounts of CP and sodium were evaluated (on DM basis): 28% CP and 0.58% sodium; 39% CP and 0.64% sodium; 52% CP and 0.76% sodium; and 64% CP and 0.87% sodium. Cats were individually housed in cages for 8 days to measure WB, urea excretion, and faecal and urine characteristics. Deuterium oxide was used to evaluate water turnover, and during the period cats were housed in a collective cattery. The data were analysed by an F test, and the means were compared by polynomial contrasts. The ɑ level of significance was set at 0.05. The methods were compared by Pearson correlation, and Bland and Altman analysis. The increase in the CP content elevated linearly the renal excretion of urea (p < .001), and, together with the higher sodium intake, elevated the renal solute load, which resulted in a linear increase in urine production and water intake (p < .01). The urine density, metabolic water, and faecal and insensible water losses did not differ (p > .05). The water flux increased linearly when using the deuterium method (p < .001), but the obtained values were 20.85 ± 11.11 ml/cat/day higher than those verified using the WB method (p = .001). Higher CP and sodium amounts in dry diets increased the urine production and water consumption of cats, and this can be explored as a possible option to increase urination.  相似文献   

Demonstration of natural killer cells (NK) in the breeding perch (Dicentrarchus labrax). Effect of breeding temperature     

P Deschaux  L Perroy-Cordier  G Peres 《Comparative immunology, microbiology and infectious diseases》1983,6(1):95-99

The role of temperature on NK cells was studied in the spleen of a fish (Dicentrarchus labrax). NK cells presence was demonstrated with a maximal cytotoxicity when animals were maintained at 18°C. An in vitro study confirmed these results.  相似文献   

The effects of crop load and irrigation rate in the oil accumulation stage on oil yield and water relations of ‘Koroneiki’ olives     

A. Naor  D. Schneider  A. Ben-Gal  I. Zipori  A. Dag  Z. Kerem  R. Birger  M. Peres  Y. Gal 《Irrigation Science》2013,31(4):781-791

The interactions between irrigation rates applied during the oil accumulation stage and crop load were studied in a six-year-old very-high-density Koroneiki (Olea europaea L.) orchard. Five irrigation rates, determined as thresholds of midday stem water potential, were applied from July 1st until harvest in 2008 and 2009 and from July 1st to the end of September in 2010. Oil yield increased with increasing crop load in all the irrigation treatments. Oil yield did not respond to increasing irrigation at very low crop load and the higher the crop load the higher the response to irrigation. There was no response to irrigation at the lowest crop loads, but the higher the irrigation rate the higher the oil yield at high crop loads. The predicted commercial oil yield at common fruit counts increased from 1.99 t/ha at the lowest irrigation rate to 3.06 t/ha at the highest irrigation rate. Stomatal conductance decreased with decreasing stem water potential but leveled off at 30–60 mmol m^?2 s^?1 at stem water potential values lower than ?4.0 MPa. High crop load increased stomatal conductance and decreased stem water potential relative to low crop load at low and medium irrigation rates. The effect of crop load on water relations became evident by the end of August and was well pronounced at the beginning of October. Physiological and irrigation water management implications related to the interactions between tree water status and crop load are discussed.  相似文献