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11.
Mushroom glucan and bovine lactoferrin (Lf), known for their immunostimulatory potential, were used as adjuvant in conjunction with a formalin-killed Aeromonas hydrophila vaccine in catla, Catla catla. In vitro antigen-specific responsiveness of catla leucocytes and protective responses against experimental challenge with homologous antigen were monitored following immunization. Antigen-specific proliferation, 'macrophage activating factor' (MAF) production and antibody production were significantly higher in fish injected with glucan adjuvanted vaccine. Lf adjuvanted preparations showed a weak proliferative response and MAF production, although the antibody production was significantly higher than the controls. A good degree of protection was achieved with the glucan adjuvanted vaccine. However, in spite of producing significant anti-A. hydrophila antibody, Lf adjuvanted vaccine did not confer any protection following challenge with A. hydrophila. The potential of adjuvanticity of mushroom glucan and bovine Lf in intraperitoneal vaccination is discussed.  相似文献   
12.
The Genus Edwardsiella comprises of bacteria differing strongly in their biochemical characteristics, physiological features, natural habitat and pathogenic properties. The most common species of the genus is Edwardsiella tarda, recovered from a variety of environmental and animal sources. In this study 51 isolates including one reference strain obtained from freshwater culture systems were analyzed for their genomic diversity by BOX-PCR and PCR-ribotyping. By comparison of fingerprint of different isolates 27 and 32 genotypes were obtained by PCR-ribotyping and BOX-PCR respectively. Cluster analysis of genetic profile obtained by BOX-PCR and ribotyping clearly showed 9 and 8 clusters respectively. Some correlation between BOX-PCR and ribotyping was observed. Several clusters delineated on the basis of source of isolation in the dendrogram by BOX-PCR with 70% cut off value had corresponding clusters in the ribotyping with 50% cut off value. Some of the genotypes were found to be habitat specific. However, there was mixing and dispersal of most of the genotypes obtained from water, sediment and fish samples. Of both the techniques, BOX-PCR was found to be more discriminating than ribotyping.  相似文献   
13.
The extent of genotypic and phenotypic diversity of Edwardsiella tarda isolated from pond sediment was assessed by SDS-PAGE, Plasmid Profiling and ERIC-PCR. SDS-PAGE of whole cell protein extracts reveals 20-23 discrete bands with molecular wt of 14-110 kDa. Several bands with molecular weight range of 38-83 kDa were present in all the isolates. Numerical analysis of protein electrophoregram delineated the isolates into four clusters. Two different types of plasmids having molecular mass of 23 kDa and 29 kDa were obtained by plasmid profiling. About 51% of the isolates carried both the plasmids. ERIC-PCR generates 3-7 bands with molecular mass of 14-1013 bp. Numerical analysis differentiated the ERIC pattern into 5 clusters at 60% similarly level. It was concluded that out of three methods ERIC-PCR was found to be more sensitive for intraspecific typing of E. tarda and can be used as a potential tool for epidemiological studies in the future.  相似文献   
14.
Summary The immune response of chicks to oral vaccination with HP1-strain of fowl pox virus was studied using intracellular virus alone or a combination of intra and extracellular viruses. The first and second vaccinations were done at four days and 25 days of age, respectively. In both groups the birds showed 50% protection against challenge virus at 32 days of age while no immunity was recorded at 95 days of age. The serum IgG concentration in both the vaccinated groups was comparable and it was significantly higher (P < 0·05) than the control birds one week after revaccination. The serum haemolytic complement activity in both the vaccinated groups was significantly lower (P < 0·05) than the control birds.
Respuesta Inmune De Pollos A La Vacunacion Oral Con Virus De Viruela Aviar Combinado Extra E Intracelular
Resumen Se estudió la respuesta inmune de pollos a la vacunación oral con la cepa HP1 de virus de viruela aviar, utilizando virus intracelular únicamente o una combinación de virus intra y extracelular. La primera y segunda vacunación fueron hechas a los 4 y 25 días de edad, respectivamente. En ambos grupos las avec mostraron 50% de protección contra la descarga viral a los 32 días de edad, mientras que no se detectó inmunidad a los 95 días de edad. La concentración sérica de I g G en ambos grupos vacunados fue comparable y fue significativemente más alta (P < 0·05) que en el grupo de aves control, una semana después de la revacunación. La actividad sérica hemolitica del complemento en ambos grupos vacunados, fue significativamente más bajo (P < 0·05) que en el grupo de aves control.

Reponse Immunitaire Du Poulet A La Vaccination Orale Avec Des Virus Combines Extra Et Intracellulaires De La Variole Aviaire
Résumé Les auteurs ont étudié la réponse immunitaire du poulet à la vaccination orale avec la souche HP1 du virus de la variole aviare, en utilisant soit le virus intracellulaire seul, soit une combinaison de virus intra et extracellulaires. La première et la deuxième vaccination ont été effectuées sur des sujects agés respectivement de 4 jours et 25 jours. Dans les deux groupes, les volailles ont montré une protection à 50 p. 100 contre le virus d'épreuve à l'âge de 32 jours, alors qu'aucune immunité n'était signalée à 95 jours. La concentration en immunoglobuline G dans les deux groupes vaccinés était comparable et significativement supérieure (P < 0,05) à celles des animaux témoins une semaine après la revaccination. L'activité du complément sérique hémolytique dans les deux lots vaccinés était significativement plus basse (P < 0,05) que celle du lot témoin.
  相似文献   
15.
The intra- and extracellular virus of three strains of fowl pox virus, when precipitated in succession with different saturation of ammonium sulphate revealed three antigens in gel diffusion test in the precipitates obtained at 25%, 50% and 75% of saturation. Further analysis of each positive antigen by dot ELISA revealed that the extracellular virus of FS-8 and HP 1 strains possessed excess antigenic protein at 50% saturation compared to their intracellular viruses. While no difference between extra- and intracellular viruses of FS-4 strain was observed.  相似文献   
16.
Swietenine, a tetranortriterpenoid, was isolated from the Swietenia macrophylla seeds. The in vivo hypoglycemic activity was evaluated against neonatal-streptozotocin induced type 2 diabetic rats. Oral administration of swietenine at 25 and 50 mg/kg body weight per day to diabetic rats was found to possess significant dose dependant hypoglycemic and hypolipidemic activity in type 2 diabetic rats.  相似文献   
17.
Abstract

Crop modelling can provide us with a vast amount of real-time information about fertilizer dose to achieve the target yield, crop conditions, etc. Nutrient-use efficiency in wheat is low because of conventional blanket and imbalanced fertilizer use. Estimation of fertilizer requirements based on quantitative approaches can assist in improving yields and nutrient-use efficiency. Field experiments were conducted in 20 sites in eastern India to assess the soil supply, requirement and internal efficiency of nitrogen (N), phosphorous (P), potassium (K) and zinc (Zn) in wheat. The data were used to calibrate the QUEFTS (QUantitative Evaluation of the Fertility of Tropical Soils) model for site-specific, balanced fertilizer recommendations. The parameters of maximum accumulation (a) and maximum dilution (d) in wheat were calculated for N (35 and 100 kg), P (129 and 738 kg), K (17 and 56 kg), and Zn (21502 and 140244 mg). Grain yield of wheat showed good correlation with N (R2 = 0.937??), P (R2 = 0.901??) and K uptake (R2 = 0.801??). The NPK ratio to produce 1 ton grain yield of wheat was derived to be 4.9:1.0:8.9. The relationships between chemical properties and nutrient supplying capacity of soils were also established. The model was validated using the data of four other experiments. Observed yields with different amounts of N, P, K and Zn were in good agreement with the predicted values suggesting that the validated QUEFTS model can be used for site-specific nutrient management in wheat.  相似文献   
18.
The amount of monosilicic acid (H4SiO4), which is the plant-available form of silicon (Si), released from fertilizers can be influenced by Si source and soil properties. A series of laboratory experiments were conducted using six soil series from Louisiana to document the differences in the release characteristics of H4SiO4 from wollastonite and slag. Monosilicic acid in solution released from slag declined with time while wollastonite consistently increased its concentration across all soil suspensions well above 40 µg mL?1. Among these soil series, soils high in organic matter and clay were seen to have maximum percent sorption (up to 79%) with minimum polymerization of H4SiO4. The presence of ions like aluminum (Al) and magnesium (Mg) enhanced the process of H4SiO4 polymerization, which led to a decrease in H4SiO4 concentration in solution. Evident relationships were observed between H4SiO4 concentration in solution with added Si sources and sorbed quantity from soil solutions.  相似文献   
19.
The Random Amplified Polymorphic DNA (RAPD) technique was used to amplify DNA segments, with the objective of finding markers linked to sex determination in male and female plants of Piper betle L. Two bulks of DNA were made drawing one each from male and female, by pooling an equal volume of DNA samples from each group of individual contributing to the bulk analysis. Fifty different random decamer primers were screened with the two bulks to identify markers associated with sex expression of which only four primers were found to be associated with sex expression. These four primers were then tested with individual plant DNA samples where sex-associated RAPD markers were identified. A ~1,400 and ~850?bp fragment from the primer OPA04 and OPN 02 respectively was found to be present in all the male individuals and absent in all the female plants. In another primer, a ~980?bp amplification product from the primer OPC 06 was present only in the female individuals. A common primer OPA 08 showed both male and female specific markers of 650 and 1,200?bp respectively. Thus, the three male- specific RAPD markers OPA041400, OPA08650 and OPN02850 and two female-specific markers OPA081200 and OPC06980 can reliably differentiate the male and female plants of P. betle L. Ploidy comparison also showed the differences in male and female plants.  相似文献   
20.
Interleukin‐10 (IL‐10) is a multifunctional cytokine and plays an important role in diseases. In this study, IL‐10 gene was cloned and characterized from catla (Catla catla), which is a highly commercially important fish species in the Indian subcontinent. The result indicated that the full‐length catla IL‐10 (cIL‐10) gene had five exons and four introns with an open reading frame of 540 nucleotides encoding a polypeptide of 179 amino acids. A phylogenetic analysis of cIL‐10 gene sequence showed that cIL‐10 clustered with freshwater carps group as expected. Quantitative real‐time polymerase chain reaction analysis showed that cIL‐10 was expressed in gill, liver, kidney, intestine, skin and heart and its expression profile was up‐regulated in bacterial infection and LPS treatment. A close relationship of high cIL‐10 expression and low pro‐inflammatory cytokine IL‐1β expression was observed in the treated group of fish, which might reveal the role of cIL‐10 as an anti‐inflammatory cytokine. Mechanism of cIL‐10 induction was investigated by blocking nuclear factor (NF)‐κB ‐signalling with BAY 11‐7082 in catla kidney cell culture. Blocking NF‐κB suppressed IL‐10 induction by LPS, and thus it revealed that cIL‐10 was induced through NF‐κB signalling. These data could be helpful to understand the function of IL‐10 in fish in response to vaccinations, probiotics and various diseases.  相似文献   
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