Effects of an indigenous and a commercial Lactobacillus buchneri strain on quality of sugar cane silage     

C. L. S. Ávila  J. C. Pinto  H. C. P. Figueiredo  R. F. Schwan 《Grass and Forage Science》2009,64(4):384-394

The aim was to evaluate the effects of adding a novel Lactobacillus buchneri strain and a commercial inoculant on the fermentation and aerobic stability of sugar cane silages (Saccharum spp.). In the first experiment samples were collected from sugar cane silage at 5, 20, 40 and 80 d after ensilage in experimental silos and microorganisms belonging to the Lactobacillus genus were isolated and identified, with a wild strain of L. buchneri, UFLA SIL 72, being selected as an inoculant. In the second experiment sugar cane was inoculated with either the novel bacteria or a commercial inoculant at the moment of ensiling and compared with a control silage prepared without an inoculant. Experimental silos were opened at 0, 3, 10, 30, 60 and 90 d of ensilage and their chemical composition measured. The silages opened after 90 d were also assessed for aerobic stability. The addition of L. buchneri resulted in a higher concentration of acetic acid and reduced populations of yeasts in silage compared to the other silage treatments, and a lower ethanol concentration in the silage. The novel L. buchneri isolate and the commercial inoculant also improved aerobic stability of the sugar cane silages. It was concluded that the addition of the novel inoculants L. buchneri UFLA SIL 72 to sugar cane silage can be recommended.  相似文献   

Suitability of different artificial diets for development and survival of stages of the predaceous ladybird beetle <Emphasis Type="Italic">Eriopis connexa</Emphasis>     

R. B. Silva  J. C. Zanuncio  J. E. Serrão  E. R. Lima  M. L. C. Figueiredo  I. Cruz 《Phytoparasitica》2009,37(2):115-123

The ladybug Eriopis connexa (Germar) (Coleoptera: Coccinellidae) is an important natural enemy of various pests. The potential of rearing it on 17 different diets was evaluated. The percentage of E. connexa adults was higher when its larvae received only eggs of Anagasta kuehniella (Zeller) (Lepidoptera: Pyralidae) after freezing for 1 day (92.5%) or combined in artificial diets with honey and water (82.5% to 100.0%). The viability from larvae to adult was 72.5% with eggs of A. kuehniella (after 1 day’s freezing) plus an artificial diet based on pet food. No adults of E. connexa were obtained with artificial diets as a stand-alone food source. The duration of the larval period to adult of this predator was longer, but with low viability, with only A. kuehniella eggs (after 6 months’ freezing) or with eggs + artificial diets. Eggs of A. kuehniella (after 1 day’s freezing) supplied separately or along with artificial diets were more appropriate to rear E. connexa and both diets can be used for mass rearing of this natural enemy.  相似文献   

Dietary methionine requirement of the pre‐adult gibel carp (Carassius auratus gibeilo) at a constant dietary cystine level          下载免费PDF全文

X. Wang  M. Xue  C. Figueiredo‐Silva  J. Wang  Y. Zheng  X. Wu  F. Han  K. Mai 《Aquaculture Nutrition》2016,22(3):509-516

A 62‐day growth trial was conducted to determine the dietary Met requirement of the pre‐adult gibel carp (Carassius auratus gibeilo) (initial weight of 51.0 ± 0.02 g). Six isonitrogenous and isoenergetic diets using fish meal, blood meal and pea protein concentrate as protein sources supplemented with crystalline amino acids were formulated to contain graded levels of dietary Met (4.44, 6.56, 8.55, 10.90, 12.79 and 15.05 g kg^?1, respectively) at a constant dietary cystine level of 3.99 g kg^?1. The results showed that weight gain rate and protein productive value significantly increased with the dietary Met levels from 4.44 to 8.55 g kg^?1, then reached plateau at 10.90 g kg^?1. Plasma HDL‐C and TC were increased with dietary Met levels. Fish supplied with 4.44–8.55 g kg^?1 Met showed lower plasma AST level than that of other groups. Plasma TG, LDL‐C and ALT levels were stable for all treatments. The activity of intestinal γ‐GT was increased with dietary Met levels. The optimal requirement of Met for pre‐adult gibel carp (>50 g) was a range from 7.86 g kg^?1 to 9.84 g kg^?1 dry diet or 16.9 g kg^?1 to 23.0 g kg^?1 of dietary protein with the presence of 3.99 g kg^?1 Cys for the satisfied lipid metabolism and maximum growth, respectively.  相似文献   

Carbon storage in the Mediterranean upland shrub communities of Montesinho Natural Park, northeast of Portugal     

Felícia Fonseca  Tomás de Figueiredo  M. A. Bompastor Ramos 《Agroforestry Systems》2012,86(3):463-475

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Influence of pyrolysis temperature on chemical and physical properties of biochar from sewage sludge     

Cícero Figueiredo  Heyder Lopes  Thais Coser  Ailton Vale  Jader Busato  Natália Aguiar 《Archives of Agronomy and Soil Science》2018,64(6):881-889

The use of sewage sludge biochar (SSB) for agro-environmental purposes has been increasing. However, due to the strong influence of pyrolysis temperatures on its production, there is great variation in its final properties. In this regard, efforts to generate relationships among many correlated SSB properties may help to understand this influence. This study sought to evaluate the effect of pyrolysis temperature on agro-environmental physicochemical properties of SSB. Biochars from sewage sludge (SS) were produced at 300, 400 and 500°C and their physicochemical properties were evaluated in comparison to SS samples. The increase in pyrolysis temperature decreased C, N, and H contents and the H/C atomic ratio, while increasing the C/N ratio. The pyrolysis process increased pH values, the surface area and pore volume and enriched the SSB with macro and micronutrients. Considering all variables together, the biochar produced at 300°C was that which showed the greatest nutrients availability, such as N total, S, NO₃^?, NH₄⁺, Ca²⁺ and Mg²⁺. Conversely, SSB produced at 500°C showed higher recalcitrant organic matter and alkalinity, important properties for C sequestration and the correction of acidic soils. The combined application of SSB produced at lower and higher pyrolysis temperatures should be furthered studied.  相似文献   

Minimum water exchange spares the requirement for dietary methionine for juvenile Litopenaeus vannamei reared under intensive outdoor conditions          下载免费PDF全文

Felipe Nobre Façanha  Hassan Sabry‐Neto  Claudia Figueiredo‐Silva  Adhemar Rodrigues Oliveira‐Neto  Alberto Jorge Pinto Nunes 《Aquaculture Research》2018,49(4):1682-1689

We examined if minimum water exchange could spare dietary methionine (Met) required for maximum growth performance of juvenile Litopenaeus vannamei reared in an intensive outdoor system. Shrimp of 1.98 ± 0.13 g were stocked at 70 animals/m² and reared for 72 days in 50 tanks of 1 m³ under flow‐through (14.4% a day) and static (1.4%–2.9% a day) green‐water conditions at 32.0 ± 3.7 g/L salinity. Five diets with a minimum inclusion of fishmeal supplemented with a dipeptide, dl ‐methionyl‐dl ‐methionine, were formulated to contain increasing levels of Met, 4.8, 6.2, 7.2, 8.1 or 9.4 g/kg (on a dry matter basis). Each of the five diets were fed four times daily to five replicate groups. Dietary Met and water exchange significantly influenced shrimp survival, gained yield, apparent feed intake, food conversion ratio and final body weight (p < .05). Raising shrimp under limited water exchange, i.e., static versus flow‐through spared the dependence on higher levels of dietary Met to maximize shrimp body weight, from 9.4 g/kg to 8.0 g/kg (14.0 and 12.6 g/kg Met+Cys respectively). In an intensive rearing system, a reduction in water exchange is desirable as it leads to a lower need for supplemental dietary Met.  相似文献   

Genetic Characterization of Antibiotic Resistance in Enteropathogenic Escherichia coli Carrying Extended‐Spectrum β‐Lactamases Recovered from Diarrhoeic Rabbits     

P. Poeta  H. Radhouani  A. Gonçalves  N. Figueiredo  C. Carvalho  J. Rodrigues  G. Igrejas 《Zoonoses and public health》2010,57(3):162-170

A total of 52 Escherichia coli strains isolated from diarrhoeic rabbits were investigated for their enteropathogenic E. coli (EPEC) pathotype by PCR amplification of eae and bfp virulence genes. A total of 22 EPEC isolates were identified, serotyped and studied for antibiotic resistance and screened for the detection of extended‐spectrum β‐lactamases (ESBLs). The EPEC isolates belonged to three serogroups (O26, O92 and O103). The most common serogroup (O103:K‐:H2) was observed among 17 EPEC strains, the O92:K‐serogroup in three isolates (the antibiotic sensitive ones) and the remaining O26:K‐serogroup in two isolates (the ESBLs isolates). Resistances to ampicillin and tetracycline were the most frequent and detected followed by resistance to nalidixic acid, streptomycin, trimethoprim–sulphamethoxazole, cefoxitin, gentamicin and ciprofloxacin. All the isolates were sensitive for amikacin, ceftazidime, aztreonam, imipenem, chloramphenicol, tobramycin and amoxicillin + clavulanic acid. Two isolates recovered from two adult animals showed an intermediate susceptibility to cefotaxime, and a positive screening test for ESBL was demonstrated in both. The bla_TEM gene was demonstrated in the majority of ampicillin‐resistant isolates. The aac(3)‐II or aac(3)‐IV genes were detected in the four gentamicin‐resistant isolates. In addition, the aadA gene was detected in 60% of streptomycin‐resistant isolates. The tet(A) or tet(B) genes were identified in all tetracycline‐resistant isolates. A total of nine EPEC isolates showed the phenotype SXT‐resistant, and the sul1 and/or sul2 and/or sul3 genes were detected in all of them. Our findings showed that the molecular detection by the eae and bfp genes by PCR followed by serotyping is useful for monitoring trends in EPEC infections of rabbits allowing the identification of their possible reservoirs. The detection of genes involved in the resistance to antibiotics of different families in a relatively high proportion of faecal E. coli isolates of rabbits is of great interest and could be considered a serious public health problem.  相似文献   

Topographical thresholds for ephemeral gully initiation in intensively cultivated areas of the Mediterranean   总被引：2，自引：0，他引：2  

L. Vandekerckhove  J. Poesen  D. Oostwoud Wijdenes  T. de Figueiredo 《CATENA》1998,33(3-4)

Ephemeral gullying is an important erosion process in Mediterranean areas suffering from land degradation because of increased drought and human impact. An ephemeral gully is formed when a hydraulic threshold for incision into a resistant soil surface is exceeded. The flow intensity at the soil surface of any landscape position is controlled by topographical parameters, such as local slope (S) and drainage-basin area (A). The objective of this study was to investigate to what extent one could use field measurements of S and A to predict the location of ephemeral gully initiation in intensively cultivated Mediterranean environments. Two relatively homogeneous study areas in Southeast Spain and Northeast Portugal with widespread ephemeral gullying were selected. S and A were measured by standard methods at the initiation point of 50 ephemeral gullies in each study area. The relationship between S and A was statistically investigated. On a double logarithmic scale, the S and A data showed considerable scatter. Orthogonal regression resulted in the threshold relationship S=aA^−b with b=0.133 for Spain, and b=0.226 for Portugal. The analysis also showed that S and A were weakly correlated for the Spanish dataset, and more strongly correlated for the Portuguese dataset. The correlation was considerably strengthened by including additional information on planform curvature and on tillage direction relative to the gully direction. Greater soil stoniness and the presence of a less permeable horizon generally increased the threshold level in both study areas. The threshold relationships resulting from this study were compared with literature data. The indices A_cS and ln(A_c/S) were applied to our study sites but neither relationship individually described the general trend between the data of S and A. Therefore, an alternative index, A_c^bS, with 0.133≤b≤0.226, according to the empirical trend between drainage basin area and local slope, was proposed to describe the topographical threshold conditions for ephemeral gully initiation in similar Mediterranean areas.  相似文献   

Sensitivity and specificity of real‐time PCR and bacteriological culture for francisellosis in farm‐raised Nile tilapia (Oreochromis niloticus L.)          下载免费PDF全文

G B N Assis  T F de Oliveira  I A Gardner  H C P Figueiredo  C A G Leal 《Journal of fish diseases》2017,40(6):785-795

Despite the worldwide occurrence of Francisella noatunensis subsp. orientalis (Fno) infection in farmed tilapia, sensitivity and specificity estimates of commonly used diagnostic tests have not been reported. This study aimed to estimate the sensitivity and specificity of bacteriological culture and qPCR to detect Fno infection. We tested 559 fish, sampled from four farms with different epidemiological scenarios: (i) healthy fish in a hatchery free of Fno; (ii) targeted sampling of diseased fish with suggestive external clinical signs of francisellosis during an outbreak; (iii) convenience sampling of diseased and clinically healthy fish during an outbreak; and (iv) sampling of healthy fish in a cage farm without a history of outbreaks, but with francisellosis reported in other farms in the same reservoir. The qPCR had higher median sensitivity (range, 48.8–99.5%) than culture (range, 1.6–74.4%). Culture had a substantially lower median sensitivity (1.6%) than qPCR (48.8%) to detect Fno in carrier tilapia (farm 4). Median specificity estimates for both tests were >99.2%. The qPCR is the superior test for use in surveillance and monitoring programmes for francisellosis in farmed Nile tilapia, but both tests have high sensitivity and specificity which make them fit for use in the diagnosis of Fno outbreaks.  相似文献   

Na+/K+-ATPase Activation by cAMP in the Midgut of Lutzomyia longipalpis (Lutz & Neiva, 1912; Diptera: Psychodidae)     

Denise Barguil Nepomuceno  Grasielle Caldas Dvila Pessoa  Ricardo Nascimento Araújo  Leonardo Barbosa Koerich  Maurício Roberto Viana Sant&#x;Anna  Marcos Horcio Pereira  Nelder Figueiredo Gontijo 《Journal of insect science (Online)》2022,22(2)

Lutzomyia longipalpis (Lutz & Neiva, 1912) females have been intensively studied regarding the regulation of midgut pH. The mechanisms involved in pH regulation are complex, and some aspects remain to be clarified. Here, we investigated the role of the Na⁺/K⁺-ATPase pump as an electrochemical potential generator and its modulation by the second messenger cAMP in the midgut of female L. longipalpis. Our results suggest that not only may Na⁺/K⁺-ATPase be the main generator of an electrochemical potential across membranes in the midgut of female L. longipalpis, but also its activity is positively regulated by cAMP. cAMP-mediated Na⁺/K⁺-ATPase pump activity might be necessary to maintain the transport of the nutrients produced during blood digestion.  相似文献