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341.
342.
Optimizing initial feeding of the Pike silverside Chirostoma estor: oil droplet depletion,point of no return,growth and fatty acid utilization in larvae fed enriched rotifers 下载免费PDF全文
M.G. Ríos‐Durán P. Navarrete‐Ramírez J. Fonseca‐Madrigal E. Mendez‐Ortiz E. Palacios I.S. Racotta C.C. Martínez‐Chávez L.G. Ross C.A. Martínez‐Palacios 《Aquaculture Nutrition》2016,22(3):517-526
The point of no return (PNR) and disappearance of the oil droplet were measured in Chirostoma estor larvae as a function of the time of first feeding. In a separate trial, growth and survival of larvae fed rotifers enriched with Chlorella sp., cod liver oil and corn oil were assessed. Fatty acid and lipid composition of eggs, oil droplets, egg yolk, feed and larvae were also evaluated. The PNR was found between 7 and 8 days posthatching (dph). Total oil droplet depletion occurred between 7 and 11 dph, depending on the time of first feeding. Best growth and survival were obtained in larvae fed with Chlorella‐enriched rotifers, followed by those fed cod liver oil‐enriched rotifers. In larvae fed corn oil, Chlorella and cod liver oil‐enriched rotifers, total oil droplet depletion took place on days 9, 10 and 11, respectively. There was a direct relationship between presence and duration of oil droplets and the survival of larvae under different starvation conditions. The feed source could prolong the existence of the oil droplet depending on particular dietary supply of essential fatty acids; the time of its disappearance could be a useful indicator of larval vigour and health status. 相似文献
343.
344.
Michelle Da Fonseca Santos Milene Möller Steven J. Clough 《Journal of Crop Improvement》2018,32(1):1-18
In Brazil, some of the most important insect pests causing damage to soybean (Glycine max) are stink bugs. Soybean production would increase if varieties with enhanced resistance were developed. The aim of this work was to examine different traits associated with plant development, and yield-related traits, in an F2:3 soybean population in a stink bug-infested field and to evaluate genetic parameters and correlations among those traits. The parents and progeny from 229 F2 plants developed by crossing a resistant cultivar (IAC-100) with a susceptible cultivar (CD-215) were evaluated in three replications in a single environment. Seven agronomic traits and eight indicators of insect resistance were measured. Genotypes showed significant differences for all traits except lodging. The grain-filling period exhibited a positive genotypic correlation of 0.66 with hundred-seed weight, whereas a negative genotypic correlation of ?0.53 was found between pod damage index (%) and weight of healthy seeds. In general, a shorter pod-filling period, lower weight of hundred-seeds, lower indices of pod damage, and higher seed-yield per plant were phenotypic traits of genotypes resistant to these insects. 相似文献
345.
M. Mejri L. Fonseca J. M. S. Cardoso M. L. Ben Jamâa I. Abrantes 《Forest Pathology》2016,46(6):663-665
Bursaphelenchus tusciae is reported for the first time in Tunisia and North Africa, associated with the insect Hylurgus ligniperda Fabricius (Coleoptera: Curculionidae: Scolytinae). Nematode identification was based on restriction fragment length polymorphism analysis and sequencing of the internal transcribed spacer (ITS) regions of ribosomal DNA. Phylogenetic analysis revealed that Tunisian B. tusciae clusters together with two other B. tusciae isolates forming a separate group close to B. hildegardae and B. eggersi. As H. ligniperda is among maritime pine scolytids pests in Tunisia and is widely distributed in North Africa, this study is an important contribution to the knowledge of Bursaphelenchus species associated with bark beetles of pine forests in Tunisia and North Africa. 相似文献
346.
José M. Vidal Alexis Fonseca Pamela Ruiz Daniela Sepúlveda Carlos Carrasco Stefano Scilipoti Javier Barros Ariel Valenzuela Ricardo Saavedra Nathaly Ruiz-Tagle Homero Urrutia 《Journal of fish diseases》2023,46(1):1-15
This study evaluated the probiotic potential of the biofilm formed by the strain Pseudomonas sp. RGM2144 on rainbow trout survival. When challenged with the fish pathogen Flavobacterium psychrophilum, Pseudomonas sp. RGM2144 increased rainbow trout survival to 92.7 ± 1.2% (control: 35.3 ± 9.5%, p < .0001). The draft genome of Pseudomonas sp. RGM2144 is 6.8 Mbp long, with a completeness 100% and a contamination of 0.4%. The genome contains 6122 protein-coding genes of which 3564 (~60%) have known functions. The genome and phylogeny indicate that Pseudomonas sp. RGM2144 is a new species in the Pseudomonas genus, with few virulence factors, plasmids, and genes associated with antimicrobial resistance, suggesting a non-pathogenic bacterium with protective potential. In addition, the genome encodes for 11 secondary metabolite biosynthetic gene clusters that could be involved in the inhibition of F. psychrophilum. We suggest that Pseudomonas sp. RGM2144 may be applied as a probiotic in salmonid fish farming. 相似文献
347.
José Marcelo Soriano Viana Ísis Fernanda de Almeida Marcos Deon Vilela de Resende Vinícius Ribeiro Faria Fabyano Fonseca e Silva 《Euphytica》2010,174(1):31-39
Best Linear Unbiased Prediction (BLUP) has become the most widely used method for genetic assessment of animal and perennial species, and it is potentially relevant for annual crops. The objective of this study was to assess this method for selection within non-inbred families in recurrent breeding programs. The ‘animal model’ was fitted. The data were expansion volume (EV) and grain yield of plants in recombination plots of two to three selection cycles in the popcorn population Viçosa, with half- and full-sib progenies. The ASReml program was used to perform the analyses. For both EV and yield the breeding values predicted from the additive and additive-dominant models were highly correlated. Multi-generation BLUP was, in general, more accurate than single-generation analysis. These two methods resulted in highly correlated predicted breeding values. The dominance genetic values predicted from the single- and multi-generation analysis were also highly correlated. The pedigree information reduced the percentage of coincidences among the selected individuals relative to phenotypic selection mainly in the population structured in half-sib families. Based on breeding values predicted by BLUP analysis, the most efficient selection procedure was mass selection. 相似文献
348.
S. Massart Y. Brostaux L. Barbarossa V. César M. Cieslinska O. Dutrecq F. Fonseca R. Guillem A. Laviña A. Olmos S. Steyer T. Wetzel J. Kummert M. H. Jijakli 《European journal of plant pathology / European Foundation for Plant Pathology》2008,122(4):539-547
The operational capacity of a duplex RT-PCR method for simultaneous detection of Prune dwarf virus (PDV) and Prunus necrotic ringspot virus (PNRSV) has been established by nine European laboratories. A total of 576 samples from Prunus trees with known sanitary status, corresponding to 32 samples in two repetitions for each laboratory, were analysed. The
level of sensitivity achieved by the method was 98.3% for PDV and 90.4% for PNRSV. The specificity was 87.4% for PDV and 94.3%
for PNRSV. The unilateral 95% confidence intervals were calculated for all these values. Cohen’s Kappa coefficient of repeatability
and reproducibility of the technique indicated a strong agreement between data. Likelihood ratios were 7.50 (positive) and
0.02 (negative) for PDV. For PNRSV, the positive likelihood ratio was 15.00 while the negative likelihood ratio was 0.11.
In addition, post-test probabilities of infection were calculated to manage the risk associated with the routine use of this
method. This allows an accurate test result interpretation to facilitate the integration of this new technique into a certification
scheme. 相似文献
349.
Evaluation of the global DNA methylation in canine mast cell tumour samples by immunostaining of 5‐methyl cytosine 下载免费PDF全文
C. Y. Morimoto M. V. Tedardi I. I. M. da Fonseca K. C. Kimura D. S. Sanches T. F. Epiphanio R. de Francisco Strefezzi M. L. Z. Dagli 《Veterinary and comparative oncology》2017,15(3):1014-1018
Cutaneous mast cell tumours (MCT) are the most common skin tumour in dogs, and to our knowledge, there are no previous studies regarding the global methylation of these tumours. DNA hypomethylation and hypermethylation have been described in several tumours and both mechanisms can lead to carcinogenesis. The purpose of this study was to evaluate the global DNA methylation in canine MCT. A total of 48 MCT samples were classified in grades 1, 2 and 3 or high‐grade or low‐grade. Monoclonal antibodies were used for the immunohistochemical detection of the 5‐methylcytosine. The immunostained nuclei were classified in strong, weak or negative pattern, and these were quantified in five distinct microscopic fields (40× objective) in each slide. The results showed that global DNA hypomethylation was predominant in grade 3, high‐grade, less differentiated MCT. These epigenetic changes in neoplastic mast cells warrant further detailed investigation aiming the establishment of tumour epigenetic therapies. 相似文献
350.
Thallyta Maria Vieira Leydiana Duarte Fonseca Gabriela Almeida Bastos Viviane de Oliveira Vasconcelos Maria Luíza França Silva Franciellen Morais-Costa Adriano Vinícius de Paiva Ferreira Neide Judith Faria de Oliveira Eduardo Robson Duarte 《Veterinary research communications》2017,41(2):99-106