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31.
Moore DP Echaide I Verna AE Leunda MR Cano A Pereyra S Zamorano PI Odeón AC Campero CM 《Veterinary parasitology》2011,175(3-4):245-251
The aim of this study was to compare the immune responses to live Neospora caninum tachyzoites and N. caninum native antigens formulated with immune stimulating complexes matrix (ISCOM-matrix) in calves. Fifteen calves were used in this study: 3 were intravenously inoculated with 1 × 10(8) live tachyzoites (Group A), 3 were inoculated twice with N. caninum native antigens formulated with ISCOMs (Group B); 3 with N. caninum native antigens in phosphate-buffered saline (PBS) (Group C); 3 received ISCOM-matrix (ISCOMs without antigen) (Group D) and 3 were negative controls receiving PBS (Group E). The last four groups were inoculated subcutaneously. The specific total IgG and its subtypes were analyzed by an indirect enzyme-linked immunosorbent assays (ELISAs) and by Western blot. IFN-γ levels in plasma was quantified using a commercial kit. All calves were challenged intravenously with 1 × 10(8) live tachyzoites at week 11 after receiving the first dose. Parasitemia was assessed in plasma samples by semi-nested PCR. Neospora-specific antibodies were detected in animals from Groups A and B in the week 2 after inoculation. The ELISA OD values were higher in Group B compared with Group A from weeks 6 to 11 (P<0.05). Analysis of the subisotype specific antibodies in experimentally infected calves revealed a predominant IgG(2) response; however, a predominant IgG(1) response was observed in animals inoculated with N. caninum native antigens formulated with ISCOM-matrix. Control calves remained seronegative until challenge infection. The pattern of bands by Western blot was similar when testing sera from animals in Groups A and B. The levels of IFN-γ production after respective immunization schedules were similar between Groups A and B. Neospora-DNA was detected in plasma samples shortly after intravenous challenge in calves from all groups including those receiving the experimental vaccine formulation. The duration of the parasitemia was similar in all groups. 相似文献
32.
R. Pereyra Lago 《African Zoology》2013,48(3):200-212
Sesarma catenata larvae were raised in the laboratory and the development stages described in detail. Larval development comprises four zoea and one megalopa stage. Morphological features of the first zoea and megalopa stages of Sesarma catenata are compared with those of other Sesarminae species described in the literature. The genera Sesarma, Metasesarma, and Bresedium appear to be closely related taxa within the subfamily. The diagnostic value of some features of larval morphology is briefly discussed. 相似文献
33.
Total and mineralizable soil carbon as affected by tillage in the Argentinean Pampas 总被引：1，自引：0，他引：1
Alejandro Costantini Helvcio De-Polli Carlos Galarza Roberto Pereyra Rossiello Romina Romaniuk 《Soil & Tillage Research》2006,88(1-2):274-278
This study was carried out in experimental plots established at Marcos Juárez, in the Pampean Region (center of Argentina) on Typic Argiudolls, with high silt content. The aim of this work was to study the effects of two tillage systems (reduced tillage and no-tillage) on the amount of total organic C, potentially mineralizable C, C released by respiration, and C stock in the topsoil of a corn (Zea mays L.)–wheat (Triticum aestivum L.)/soybean (Glycine max L. Merr.)–soybean rotation. No-tillage showed C stock greater than reduced tillage only at 0–5 cm depth, but not at 0–20 cm, even though in situ respiration was lower. As a consequence, no tillage did not show a differential capacity for C sequestration in comparison with reduced tillage. 相似文献
34.
G Vichera J Alfonso CC Duque MA Silvestre F Pereyra‐Bonnet R Fernández‐Martín D Salamone 《Reproduction in domestic animals》2010,45(6):e306-e312
The aim of this study was to evaluate the potential of dehydroleucodine (DhL), a new drug isolated from a medicinal herb used in Argentina, for activation of bovine oocyte. Several DhL concentrations and exposure times after ionomycin (Io) treatment were tested. The optimal DhL treatment, found for parthenogenetic development, was employed to produce bovine embryos by intracytoplasmic sperm injection (ICSI) and somatic cell nuclear transfer (SCNT). The best parthenogenic embryo developments were observed with 5 μm Io for 4 min followed by 5 μm DhL concentration and after 3‐h exposure time (52.3% cleavage; 17.4% morulae; 7.3% blastocyst; n = 109). This treatment generated no significant differences with standard Io plus 6‐dimethylaminopurine (DMAP) treatment in preimplantation embryo development. In our conditions, the embryo development reached after ICSI and SCNT assisted by the DhL treatment did not differ in terms of cleavage and blastocyst development from activation with standard Io plus DMAP treatment (p > 0.05). In conclusion, DhL utilization to activate oocytes and induce development of parthenogenotes, ICSI‐embryos or SCNT‐embryos is reported here for first time. 相似文献
35.
Probiotic characteristics and aflatoxin B1 binding ability of Debaryomyces hansenii and Kazaschtania exigua from rainbow trout environment 
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下载免费PDF全文 María P Martínez María L González Pereyra María G Fernandez Juri Valeria Poloni Lilia Cavaglieri 《Aquaculture Research》2018,49(4):1588-1597
The aim of this study was to evaluate probiotic properties and the aflatoxin B1 adsorption ability of yeasts isolated from rainbow trout intestine and fish feed to assess their use in the formulation of feed additives. Growth at pH 2, bacterial pathogens inhibition, bacterial pathogens co‐aggregation, autoaggregation, homologous and heterologous inhibition against lactic acid bacteria were evaluated. Moreover, aflatoxin B1 adsorption was tested. All strains were able to maintain viable (107 cells/ml) at pH 2. All strains isolated from intestine were identified as Kazaschtania exigua, while strains isolated from feed were all identified as Debaryomyces hansenii. Kazaschtania exigua RC035 and RC037 showed the strongest antimicrobial activity while K. exigua RC037 and RC038 were the most efficient co‐aggregating bacterial pathogens. All strains exhibited strong autoaggregation. None of the tested yeast strains showed homologous inhibition towards other yeasts and heterologous inhibition towards lactic acid bacteria strains. Debaryomyces hansenii RC031 demonstrated aflatoxin B1 adsorption capacity (21%). The results of the present study indicate that select strains of Kazaschtania exigua and D. hansenii showed potential to improve the health of rainbow trout by inhibiting pathogens and binding AFB1 and their use as probiotics may improve the production of rainbow trout in aquaculture systems. 相似文献
36.
Jose Luis Sánchez‐Salgado Mohamed Alí Pereyra Concepción Agundis Oscar Vivanco‐Rojas Claudia Sierra‐Castillo Juan José Alpuche‐Osorno Edgar Zenteno 《Aquaculture Research》2017,48(8):4001-4011
Several lectins have been found in crustaceans, and it has been suggested that they play roles in cell signalling, cell–cell interaction, protein synthesis and pathogen recognition. These functions are performed through their specificity for carbohydrates. This review analyses the carbohydrate specificity, tissue distribution and participation in the immune responses of lectins in crustaceans. Furthermore, we explore some data showing that lectin expression seems to be stimulated by pathogens, favouring crustacean survival. 相似文献