Spinosad‐mediated effects on the walking ability,midgut, and Malpighian tubules of Africanized honey bee workers          下载免费PDF全文

Marcos Pereira Lopes  Kenner Morais Fernandes  Hudson Vaner Ventura Tomé  Wagner Gonzaga Gonçalves  Franciane Rosa Miranda  José Eduardo Serrão  Gustavo Ferreira Martins 《Pest management science》2018,74(6):1311-1318

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Influence of biofilm on the production of <Emphasis Type="Italic">Farfantepenaeus paulensis</Emphasis> in pens in the Patos Lagoon estuary     

Eduardo Luis Cupertino Ballester  Fabrício Martins Dutra  Tito Luís Pisseti  Ronaldo Olivera Cavalli  Paulo César Abreu  Wilson WasieleskyJr 《Aquaculture International》2018,26(3):713-726

The objective of the present work was to determine the influence of artificial substrates that increase the area for biofilm development on the production performance of Farfantepenaeus paulensis juveniles in pens. Shrimp were stocked at a density of 20/m² in pen structures (bottom area?=?50 m²) that were installed in the Patos Lagoon estuary. Two treatments with three repetitions were analyzed, where artificial substrates (polyethylene nets—1-mm mesh size) were added to increase the area for biofilm development by 100%, and where no substrates were added. During the experimental period, the biomass and the composition of the biofilm were assessed. After 86 days of rearing, no significant differences were found in shrimp performance between the treatments (p?>?0.05). However, the examination of the chlorophyll a, dry weight, and composition of the biofilm indicated that the shrimp were actively consuming the biofilm attached to the artificial substrates. Significant decreases in the abundances of nematodes >?500 μm after the 56th day and of tintinnids and rotifers between day 28 and day 42, indicated that the shrimp were selectively predating on these organisms. Moreover, a decrease in the chlorophyll a concentration in the biofilm suggests that the shrimp were consuming the microalgae. Although the increase in the area for biofilm development did not improve shrimp performance, the shrimp presented the highest growth rates when they consumed most of the biofilm microorganisms.  相似文献   

Digestive enzyme activity in the intestine of Nile tilapia (<Emphasis Type="Italic">Oreochromis niloticus</Emphasis> L.) under pond and cage farming systems     

Juliana Ferreira Santos  Karollina Lopes Siqueira Soares  Caio Rodrigo Dias Assis  Carlos Augusto Martins Guerra  Daniel Lemos  Luiz Bezerra CarvalhoJr.  Ranilson Souza Bezerra 《Fish physiology and biochemistry》2016,42(5):1259-1274

The effect of different farming systems (cage, pond) upon digestive enzyme activities of Nile tilapia was evaluated. Juvenile Nile tilapia (87.61 ± 1.52 g) were simultaneously cultured in pond and cage systems during 90 days. Cages used nutritional biphasic plan (35 and 32 % crude protein—CP feeds) and ponds used nutritional triphasic plan (35, 32 and 28 % CP feeds). Biometric measurements were monthly performed for adjustments in feeding regimes and removal of intestine tissues to evaluate the performance of enzyme activities. Total proteolytic, amylase and lipase activities were not statistically different between the treatments throughout the periods analyzed (31, 63 and 94 days of culture). However, trypsin and chymotrypsin activities were higher with 31 and 63 days of culture in fish from pond system, suggesting that natural food may have influenced these activities. A positive correlation was observed between the recommended concentration of essential amino acids for Nile tilapia and specific aminopeptidases activity in fish cage system. Substrate–SDS–PAGE revealed 12 active proteolytic bands in both systems. However, integrated density (ID) values were higher in the bands of ponds. Specimens of either cage or pond exhibited five bands of amylolytic activity. Fish from cage and pond systems showed the highest values of ID within 31 days of cultivation. In this study, the complexity of digestive functions could be verified for animals maintained under commercial conditions. Some of the assessed enzymes may show adaptations of their activities and/or expression that allow the fish to achieve a more efficient nutrient assimilation.  相似文献   

Sources of resistance to cassava root rot caused by Fusarium spp.: a genotypic approach     

Sandielle Araújo Vilas Boas  Camila Santiago Hohenfeld  Saulo Alves Santos de Oliveira  Vanderlei da Silva Santos  Eder Jorge de Oliveira 《Euphytica》2016,209(1):237-251

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Trophic State Evolution over 15 Years in a Tropical Reservoir with Low Nitrogen Concentrations and Cyanobacteria Predominance     

Frederico Guilherme de Souza Beghelli  Daniele Frascareli  Marcelo Luiz Martins Pompêo  Viviane Moschini-Carlos 《Water, air, and soil pollution》2016,227(3):95

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Assessment of Anthropogenic Impacts on the Water Quality of Marreco River,Brazil, Based on Principal Component Analysis and Toxicological Assays     

Soraya Moreno Palácio  Fernando Rodolfo Espinoza-Quiñones  Aline Roberta de Pauli  Pitágoras Augusto Piana  Caroline Bressan Queiroz  Simony Camila Fabris  Márcia Regina Fagundes-Klen  Márcia Teresinha Veit 《Water, air, and soil pollution》2016,227(9):307

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Modelling transport of chokka squid (Loligo reynaudii) paralarvae off South Africa: reviewing,testing and extending the ‘Westward Transport Hypothesis’     

Rodrigo S. Martins  Michael J. Roberts  Christophe Lett  Nicolette Chang  Coleen L. Moloney  Maurício G. Camargo  Erica A. G. Vidal 《Fisheries Oceanography》2014,23(2):116-131

Annual landings of chokka squid (Loligo reynaudii), an important fishing resource for South Africa, fluctuate greatly, and are believed to be related to recruitment success. The ‘Westward Transport Hypothesis’ (WTH) attributes recruitment strength to variability in transport of newly hatched paralarvae from spawning grounds to the ‘cold ridge’ nursery region some 100–200 km to the west, where oceanographic conditions sustain high productivity. We used an individual‐based model (IBM) coupled with a 3‐D hydrodynamic model (ROMS) to test the WTH and assessed four factors that might influence successful transport – Release Area, Month, Specific Gravity (body density) and Diel Vertical Migration (DVM) – in numerical experiments that estimated successful transport of squid paralarvae to the cold ridge. A multifactor ANOVA was used to identify the primary determinants of transport success in the various experimental simulations. Among these, release area was found to be the most important, implying that adult spawning behaviour (i.e., birth site fidelity) may be more important than paralarval behaviour in determining paralarval transport variability. However, specific gravity and DVM were found to play a role by retaining paralarvae on the shelf and optimizing early transport, respectively. Upwelling events seem to facilitate transport by moving paralarvae higher in the water column and thus exposing them to faster surface currents.  相似文献   

Biotechnology of the multipurpose tree species Arbutus unedo: a review     

Jo?o Martins  Glória Pinto  Jorge Canhoto 《林业研究》2022,(2):377-390

Arbutus unedo L. (strawberry tree, Ericaceae) is a woody species with a circum-Mediterranean distribu-tion. It has considerable ecological relevance in southern...  相似文献   

Impact of 24-h Cooling Prior to Freezing on the Survival of Domestic Cat (Felis catus) Epididymal Sperm     

JLA Martins  AISB Villaverde  AFM Lima  PVM Steagall  JCP Ferreira  CA Taconeli  MD Lopes 《Reproduction in domestic animals》2009,44(S2):366-368

The aim of this study was to investigate the impact of a 24-h cooling period prior to freezing on domestic cat epididymal sperm viability. Fifteen tomcats were submitted to routine orchiectomy and sperm samples were retrieved from both epididymides in a Tris–glucose–20% egg yolk extender. For each tomcat, the diluted sperm was split into two equal volumes and cooled to 5°C at a rate of 0.5°C/min; one sample for 60 min (control) and the other for 24 h (cooled). After the cooling period, samples from both groups were frozen using an identical freezing protocol. Sperm samples were evaluated in three different periods: immediately after harvesting, after cooling at 5°C for 24 h (cooled group) and after freezing–thawing of control and cooled groups. Evaluations consisted of sperm motility and progressive status, sperm morphology and plasma membrane integrity (PMI) using two fluorescent probes. After cooling for 24 h, a decrease (p < 0.05) in sperm motility, progressive status and PMI was observed when compared to sperm samples immediately after collection. Comparing the results obtained after thawing, no difference (p < 0.05) was found regarding sperm motility, progressive status, PMI and sperm morphology between control and cooled groups. The results from the present study show that cooling cat epididymal spermatozoa at 5°C for 24 h prior to freezing does not lead to major damage of spermatozoa impairing the freeze–thaw process.  相似文献   

Fertilizing Capacity of Frozen Epididymal Sperm Collected from Dogs     

MIM Martins  LC Padilha  FF Souza  MD Lopes 《Reproduction in domestic animals》2009,44(S2):342-344

The collection of epididymal sperm may be a valuable tool for canine reproduction especially since it can enable collection of cells after death of a valuable dog. The aim of the present study was to evaluate the viability of epididymal sperm after freeze-thawing. Epididymides were obtained from four adult dogs by elective orchiectomy. The caudal portion of the epididymides and part of the deferential ducts were squeezed by means of an anatomic clamp into a Petri dish containing either 0.9% saline solution (Group 1) or Ringer solution without lactate (Group 2). Samples were centrifuged at 800 ×  g for 10 min, the supernatant was removed and the pellet was diluted in one step with a Tris/citric acid/OEP (Orvus Es Paste) extender containing 7% glycerol and subjected to semen freezing. Oocytes were obtained from canine ovaries, after ovariohysterectomy. Only oocytes that were approximately 100 μm in diameter, with a dark ooplasm surrounded by three- or four-well formed cumulus cell layers were used for sperm testing. Frozen semen samples were thawed in a water bath at 70°C for 8 s and analysed at room temperature for sperm motility and velocity. Oocytes were incubated with spermatozoa in humidified atmosphere containing 5% CO₂ at 38°C for 18 h. Morphological and functional characteristics of spermatozoa were similar in both groups. However, the percentage of sperm cells bound to oocytes was significantly higher in Group 2 than in Group 1. This result suggests that the Ringer solution without lactate was a more suitable medium for collecting epididymal canine sperm than 0.9% saline.  相似文献