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Proteus infection was incriminated as the cause of severe depression, coma, and high mortality in successive broods of quail chicks. The pathological lesions comprised congestion of lungs, liver, and kidneys and mucus exudation in the trachea. The organism, isolated from the heart blood and lungs of affected chicks, was identified on biochemical tests as Proteus mirabilis. Pathogenicity of the isolate was tested in young albino mice and week-old quail chicks, which succumbed to infection within 48 hours of inoculation. Association of P. mirabilis with septicemic disease in Japanese quails has apparently been demonstrated for the first time.  相似文献   
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In vitro studies with organ (oviduct and trachea) and chicken embryo kidney cell cultures were attempted to assess the pathogenicity of locally isolated infectious bronchitis virus (IBV-P:120) initially isolated from the oviduct of young chicks. In oviduct cultures infected with IBV, ciliary movements decreased as early as 24 hours postinoculation (PI), and on the 6th day ciliary movements ceased completely. Cytopathic changes were also noticed. Immunofluorescent antigen was detected from 1 to 6 days PI, the maximum being on the 3rd day. The characteristic microscopic changes in the oviduct explants were reduced by 24 hours PI and had completely ceased on the 5th day. Cytopathic effect and immunofluorescent antigen were present from 1 to 8 days PI, being maximum on the 5th day. Histological changes marked by loss of cilia, rounding of the epithelial cells, degeneration, and sloughing were detected from 2 to 8 days PI. Low-embryo-passaged (EP-7) IBV did not produce cytopathic effect on the chicken embryo kidney cell cultures. On the contrary, high-embryo-passaged (EP-14) virus produced cytopathic effect at the third tissue-culture-passage level.  相似文献   
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Marek's disease-associated tumour surface antigen (MATSA) removed by enzymatic (papain) digestion of Marek's disease tumour cells was fractionated by gel filtration chromatography. The first peak (F1) was used to raise antibody in rabbits. Monoclonal antibody (RPH-6) directed against MATSA and the anti-F1 IgG were used as idiotypic antibodies to raise polyclonal anti-idiotype serum in heterologous hosts; rabbit and goat, respectively. The anti-idiotypes (anti-Id) were purified by affinity chromatography and characterized by competitive binding assay using immunofluorescent (IF) tests.

Day-old white Leghorn chicks were immunized with anti-Id to MATSA (Group 1) or anti-Id to F1 (Group 3) and challenged with virulent Marek's disease virus (MDV) on the tenth day post immunization. In positive control groups, the day-old chicks were inoculated with anti-BALB/c mouse globulin (Group 2) and anti-rabbit globulin (Group 4) and challenged with virulent MDV on the tenth day post inoculation. As compared with positive control groups, the vaccinated groups (1 and 3) had considerably lower level of MATSA positive cells during the post challenge observation period. The protection level against MD in the immunized groups was 66.6% (Group 1) and 86.6% (Group 3).  相似文献   

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Egg yolk-Tris is most commonly used semen extender; however, its use involves hygienic risk, interference with fertility and poor microscopic examination. Therefore, replacement of egg yolk with a plant-based component with protective effects on spermatozoa would be advantageous. In present study, we observed effect of soya milk-based extenders on dilution and liquid preservation of Murrah buffalo bull semen at 5°C up to 72 h in comparison with conventional egg yolk-Tris extender (Ext.1). In experiment one, a total of 32 buffalo semen ejaculates from four animals were extended and preserved at 5°C for 72 h in soya milk-based extender (Ext.2) with different percentages (10%, 15%, 20%, 25% and 30%) of soya milk for optimization of soya milk concentration. Semen quality was assessed for individual motility, viability, membrane integrity and acrosome integrity at 0, 24, 48 and 72 h of liquid preservation. The results of experiment one indicated that 25% soya milk is an optimum concentration for buffalo bull semen extender preparation. A modified method was used to prepare another soya milk-based extender (Ext.3). In the second experiment, two soya extenders (Ext.2 and 3) with optimized concentration (25%) of soya milk were comparatively assessed with egg yolk-Tris extender (Ext.1) for semen quality parameters at 0, 24, 48 and 72 h of liquid preservation. The individual sperm motility at 0 and 24 h following dilution were found non-significant among extenders. However, after 48 h of dilution, individual motility in Ext.3 was observed significantly (p < 0.05) higher than Ext.1. After 24, 48 and 72 h of dilution sperm membrane integrity in Ext.3 was found significantly (p < 0.05) higher than Ext.1. Overall, comparative evaluation of sperm parameters obtained revealed that Ext.3 containing 25% soya milk can be used as a substitute of egg yolk-based extender for buffalo semen liquid preservation.  相似文献   
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The applicability of PCR-RFLP of 16S rDNA and conventional phenotypic methods for differentiation of Edwardsiella tarda associated in freshwater fish culture system was studied. In this study, by conventional biochemical tests and antibiotic resistant patterns 2 and 14 groups were obtained. But these methods failed to discriminate the isolates habitat wise. However, PCR-RFLP of 16S rDNA was found to be specific to detect habitat-specific isolates. All the fish isolates belonging to particular genotypes were found only in fish, not in water or sediment. Some of the genotypes were exclusively present in water and sediment. This study indicates the prevalence of site-specific genotypes in freshwater ecosystems. Molecular method is found to be superior to discriminate the E. tarda habitat wise to conventional typing methods.  相似文献   
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The climatic data for 17 years from 1988 to 2004 of the rainfed hill plateaus of Kandhamal district of Orissa (India) were analyzed to find out the monthly climatic index from the calculated values of effective rainfall and evapotranspiration. The 80% dependable monthly climatic index was correlated with crop coefficient and suitable cropping period and sequences for the study area were suggested based on it. The extent of investment, net return and soil loss from agriculture were estimated as per the present condition and for the suggested cropping patterns. A mathematical model was formulated for optimal allocation of area to different crop sequences with different objectives viz. minimization of soil loss, minimization of investment and maximization of net return from agriculture and was solved using linear goal programming technique. The model suggested to take up food crops in area of 1,30,777 ha and perennial grass cover in 3223 ha with a cropping intensity of 1.61 resulting in a net return of Rs 1064.775 millions sustaining soil loss to a tune of 9489.67 thousand tons per year. The model was found to be favourable in respect of higher net return of Rs 8862.34 and lesser soil loss of 23.41 tons/ha than the corresponding present values. But more investment of Rs 4489.01 per ha was required to fulfill the objectives.  相似文献   
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