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101.
G. R. Xavier L. M. V. Martins M. C. P. Neves N. G. Rumjanek 《Biology and Fertility of Soils》1998,27(4):386-392
A large collection of cowpea rhizobia strains was obtained from soil samples collected from either a semi-arid or a tropical
rain forest area located at about the same latitude in the north-eastern region of Brazil and evaluated for their intrinsic
antibiotic resistance to eight commercial antibiotics. The aim of this study was to correlate antibiotic resistance of native
rhizobia strains to edaphic-climatic factors as a way to establish suitable inoculants for specific areas. A large diversity
regarding intrinsic antibiotic resistance was found, and 17 clusters were identified as varying from sensitive to gradually
resistant up to 500 μg·ml–1 of the antibiotics tested. Clustering analysis did not show any pattern related to the geographic region where isolates have
been obtained. On the other hand, an increase in the antibiotic-resistant rhizobia population was associated with an increase
in soil P and Al contents. lsolates which were sensitive to spectinomycin, ampicillin, streptomycin, chloramphenicol and tetracycline
were present at higher rates in soils devoid of Al. Rhizobia bacteria producing mucus type I (fluid and capable of spreading
over the solid media) were found preferentially in soil with Al concentrations up to 36 mg·kg–1, diminishing quickly at higher levels.
Received: 2 May 1997 相似文献
102.
Ammonia is considered a key component in the attraction of tephritid flies to protein-based lures. The addition of ammonium acetate to improve hydrolyzed protein-borax mixtures used to monitor tephritids has not been evaluated, although it has improved attraction to toxic baits. The presence of ammonium acetate crystals in a ventilated tube inside a trap containing hydrolyzed protein + borax, did not improve the capture of Anastrepha obliqua or Anastrepha serpentina flies in field experiments when compared with hydrolyzed protein + borax alone. In contrast, the addition of 1% ammonium acetate into the drowning solution of a hydrolyzed protein + borax mixture resulted in significantly reduced captures of both pests. Laboratory tests indicated that the emission of ammonia gas was increased 1.6–4.5-fold from traps that included ammonium acetate. These results confirm the hypothesis that a higher release of ammonia does not improve the attraction of tephritids when protein-derived odors are also present. 相似文献
103.
Ariana Silva Guimarães Paulo Travassos Pedro Walfir Martins E Souza Filho Fabrício Dias Gonçalves Francisco Costa 《Aquaculture Research》2010,41(6):828-838
The conversion of mangrove areas into shrimp farming ponds has been indicated as the main activity responsible for the reduction in the area of this ecosystem along the northeastern coast of Brazil. The present study was conducted using remote sensing methods and a geographical information system with the aim of quantifying the participation of this activity in the reduction of the mangrove areas along the northern coast of the State of Pernambuco (northeast, Brazil), where shrimp farming has been implanted in last recent years. From 1973 to 2005, there was reduction of about 2.052 ha of mangrove, 197 ha of which were converted into shrimp ponds. Thus, the real contribution of shrimp farming to this reduction was just 9.6% of the total area. Other anthropogenic activities, such as agriculture, urban expansion and tourism, contributed greatly to the reduction in the mangrove areas along the northern coast of the State of Pernambuco. 相似文献
104.
Kennya Gomes Silva Addam Scheila Anelise Pereira Gabriel Fernandes Alves Jesus Lucas Cardoso Nichola Syracuse Gustavo Ruschel Lopes Nicollas Breda Lehmann Bruno Correa da Silva Lúvia Souza de S Francisco Clio Maia Chaves Maurício Latera Martins Jos Luiz Pedreira Mourio 《Aquaculture Research》2019,50(10):2960-2971
This study evaluated the effects of dietary supplementation of organic acids blend (OAB) alone or in combination with essential oil, Lippia origanoides (OAE) for Nile tilapia fed supplemented diets for 30 days. Fish (1.1 ± 0.04 g) were fed control (Control), or OAB 0.5% or OAB 0.5% + essential oil 0.125% (OAE) respectively. At the end of the experiment, samples were collected for de hemato‐immunological, histological analysis of the intestine and liver, as well as microbiology of the intestine. The pH of the diets supplemented with OAB and OAE reduced 0.92 and 0.19 respectively. The growth and FCR were unaffected by the treatments, but survival was significantly higher in the OAB treatment. Fish fed the OAB diet showed reduced concentration of total heterotrophic bacteria and Pseudomonas sp. in the intestine. Increased glucose in fish fed OAB and high number of circulating monocytes in fish fed OAE diet were observed. The anterior intestine of fish fed OAE diet showed larger number of goblet cells and increased villi height. The diet supplemented with OAB, mainly, improved the intestinal health and survival of tilapia juveniles and can be used in juvenile production. 相似文献
105.
106.
Martins ML Vieira FN Jerônimo GT Mouriño JL Dotta G Speck GM Bezerra AJ Pedrotti FS Buglione-Neto CC Pereira G 《Fish physiology and biochemistry》2009,35(1):219-222
This study evaluated the total and differential leukocyte counting and the phagocytic activity in Nile tilapia Oreochromis niloticus experimentally injected with Enterococcus sp. in the swim bladder. Fish were distributed in four treatments in triplicates of non-injected fish, fish injected with
1 ml of sterile saline solution 0.65%, and fish injected with 1 × 103 and 1 × 106 colony-forming units (CFU) of Enterococcus diluted in 1 ml sterile saline. Twenty-four hours after injection, the fish were anesthetized and the blood collected for
white blood cell (WBC) counts, differential counting of WBC, and phagocytic activity of blood leukocytes. The increased numbers
of WBC and lymphocytes were followed by decreased number of monocyte after infection. The percentages of phagocytic activities
in the blood were 55.3 and 55.9%, respectively, in tilapia injected with 1 × 103 and 1 × 106 CFU/ml. 相似文献
107.
Rodrigo C. Silva Virgínia B. Richini-Pereira Mariana Kikuti Pâmela M. Marson 《The Veterinary quarterly》2017,37(1):23-30
Background: Canine visceral leishmaniasis (CVL) is a worldwide parasitic zoonosis caused by Leishmania (Leishmania) infantum around the world. Canids are the definitive hosts and sand flies the intermediate hosts.Objective: To test the hypothesis that a new species-specific primers (Lch14:Lch15, targeting a multiple alignment for L. infantum kDNA minicircle) is an efficient diagnostic tool for L. infantum.Methods: The presence of L. infantum DNA was assessed in blood samples of 69 stray dogs using the conventional PCR (cPCR) and quantitative PCR (qPCR). Additional 50 lymph nodes and 50 bone marrow samples (positive and negative samples for parasitological tests) from dogs from endemic and nonendemic areas for CVL were also used. Results: L. infantum strains, and all positive lymph node and bone marrow samples for parasitological test gave positive results for cPCR and qPCR, presenting analytical sensitivity of ~100 parasite mL?1. For the blood samples, 40/69 (58%; CI 95%; 46%–69%) resulted positive for L. infantum in both tests. All positive samples were confirmed by sequencing.Conclusion: This study showed the importance of the specific detection of L. infantum based on species-specific primers by molecular techniques, highlighting the application as a confirmation method in epidemiological studies and to adopt the best control measures. 相似文献
108.
Salty stories,fresh spaces: Lessons for aquatic protected areas from marine and freshwater experiences 下载免费PDF全文
Erin K. Loury Shaara M. Ainsley Shannon D. Bower Ratana Chuenpagdee Tracy Farrell Amanda G. Guthrie Sokrith Heng Zau Lunn Abdullah Al Mamun Rodrigo Oyanedel Steve Rocliffe Suvaluck Satumanatpan Steven J. Cooke 《水产资源保护:海洋与淡水生态系统》2018,28(2):485-500
109.
A combination of plant oils promotes adequate growth of the freshwater catfish Rhamdia quelen (Quoy & Gaimard 1824) 下载免费PDF全文
Rodrigo Javier Vargas Alexandre Sachsida Garcia Sueli Regina Baggio Eduardo Cargnin‐Ferreira Débora Machado Fracalossi 《Aquaculture Research》2015,46(12):3046-3055
Essential fatty acids should be included in the diet to ensure adequate fish growth. Despite the great number of studies on fatty acid nutrition of fish, there are still several unknowns. The aim of the present study was to investigate fatty acid nutrition of jundiá, a Latin American freshwater catfish. Four diets were formulated containing (i) coconut oil (?C, negative control), (ii) coconut oil + high‐docosahexaenoic‐acid‐fish oil (+C, positive control) and coconut + sunflower + linseed oils at different ratios, producing either (iii) a diet rich in linoleic acid (LA) (HighLA) or 4) a diet low in LA (LowLA). All diets contained significant amounts of saturated fatty acids (at least 57.5% total fatty acids in HighLA) and monounsaturated fatty acids (at least 19.1% total fatty acids in ?C). Diets were fed to jundiá fingerlings (1.5 g) for 70 days; growth, body composition and liver histology were evaluated. The ?C diet, without essential fatty acids, promoted significantly lower fish growth, body fat accumulation and hepatic lipidosis. Fish fed HighLA and LowLA diets presented similar growth as fish fed +C diet. These findings suggest that diet formulations for jundiá catfish fingerlings can include only plant oils without negative effect on growth, survival, body composition, fish health or parameters of feed utilization (ingestion rate and protein utilization). 相似文献
110.
Figueiredo JF Martins MS Ribeiro MF Passos LM 《Journal of veterinary medicine. B, Infectious diseases and veterinary public health》2000,47(2):121-126
A panel of monoclonal antibodies was produced and characterized by an indirect fluorescent antibody test (IFAT), an enzyme-linked immunosorbent assay (ELISA) and Western blotting with the aim of identifying antigens of Babesia bovis. After fusion, the resultant hybrids were selected by the IFAT, cloned, maintained in culture in vitro, and cryopreserved in liquid nitrogen. Ten clones producing monoclonal antibodies were found to react against the entire merozoites, three reacted on the surface of the merozoites, and one clone reacted against the polar region of the merozoites. All monoclonal antibodies reacted in ELISA, with the optical density varying from 0.368 to 0.502 (cut off = 0.022). The bands recognized by the monoclonal antibodies in Western blotting had molecular weights ranging from 162 to 19 kDa. Four clones recognized a single band of 73 kDa, and another four did not react in Western blotting. 相似文献