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1.
Antibodies to bovine serum albumin were detected in swine sera by use of an immunoblotting technique. Such sera had false-positive reactions, as determined by results of African swine fever virus serodiagnostic techniques when bovine serum albumin was a contaminant in the soluble cytoplasmic antigen obtained from infected cells cultured in the presence of bovine serum. The soluble cytoplasmic antigen obtained from cell cultures infected with African swine fever virus in the presence of porcine serum did not react with the false-positive sera and, therefore, was used for African swine fever virus serodiagnostic methods, with 0% false-positive results.  相似文献   
2.
The purpose of this study was to determine the rate of decline and geographical distribution by municipality of clinical and subclinical African swine fever (ASF) in the affected areas of Spain. A second aim was to evaluate the performance of diagnostic tests in the Spanish ASF eradication program. Clinical outbreaks were confirmed using both the direct and indirect immunofluorescence test (and if both were negative, by the hemabsorption test). The serological status of swine was determined by an enzyme-linked immunosorbent assay (ELISA) and suspect serum samples were confirmed by the immunoblot assay.

The number of clinical outbreaks (herds) of ASF for 1989, 1990 and 1991 was 170, 347 and 207, respectively. The numbers of municipalities within each affected province experiencing acute outbreaks for the same time periods were 49, 69 and 48, respectively. Serologically diagnosed animals positive for ASF were 1.1% of animals tested in 1989, 0.5% in 1990 and 0.8% in 1991. The corresponding positive predictive values of the standard ELISA test used were 99.0, 97.9 and 98.8, respectively. Similarly, the number of municipalities within each affected province experiencing serologically positive subclinically infected animals was 269, 178 and 147 for each of the years 1989, 1990 and 1991, respectively.  相似文献   

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4.
The pathogenicity of 10 bacterial isolates was investigated on potato, radish, carrot and beet, including sensitivity and pathogen control efficacy. The isolates were identified by morphological, biochemical and molecular methods. All isolates were pathogenic on radish, carrot, and beet, and were highly virulent on potato. Although the isolates were obtained from different locations in the El Fuerte Valley (Sinaloa, Mexico), they were similar in their morphological, physiological and biochemical characteristics. Sequences of the 16S rRNA gene obtained by PCR were identical for all isolates. These results indicate that the bacterial isolates from potato scabby tissue belong to S. acidiscabies. Furthermore, the effectiveness of fluazinam, both in vitro and under greenhouse and field conditions, represents a possibleoption for chemical control of potato common scab disease. While our results suggest that spraying at seeding is effective in controlling common scab, future studies to combine this treatment with seed dressing before planting will be conducted to determine if there is an increase in disease control.  相似文献   
5.
In order to obtain a better understanding of the active defense strategy of cherimoya (Annona cherimola Mill.) fruit, hydrolytic and antifungal activity, as well as expression of proteins functionally and immunogenically related to the pathogenesis-related proteins chitinase (PR-Q) and 1,3-β-glucanase (PR-2), were estimated in fruit at different ripening stages. Increase in expression of the 27 kDa constitutive chitinase and the induction of two new proteins, a 26 kDa chitinase and a 51 kDa 1,3-β-glucanase were associated with enhanced in vitro hydrolytic and antifungal activity of the acidic protein extract in ripe fruit. Ripening modified the expression of constitutive basic isoenzymes, with a sharp decrease in both relative accumulation and hydrolytic activity. Likewise, a new basic 33 kDa chitinase was induced in the over-ripe fruit, concomitant with accumulation of a basic constitutive 76 kDa 1,3-β-glucanase. At this stage, the basic protein extract modified in vitro growth inhibition of Botrytis cinerea. Short-term high CO2 treatment delayed fruit ripening and maintained a similar distribution of activity and isoenzymatic pattern in both protein fractions to that in unripe fruit. These results indicate that the changes in the pattern of defense proteins and hydrolytic activity in cherimoyas appear to be associated with ripening. Moreover, unlike the constitutively expressed isoenzymes, only the transitorily induced chitinases and 1,3-β-glucanases were associated with an active defense-related response.  相似文献   
6.
An immunoblotting assay has been adapted to detect antibodies against African swine fever virus. The electrophoretic transfer of proteins and the immunoreaction conditions were optimized, using 4 mA/cm2 of current intensity and 10 micrograms of soluble cytoplasmic antigen of infected cells per strip. Filters of polyvinylidene difluoride showed the highest capacity for protein absorption, but nitrocellulose filters showed lower backgrounds. The specificity and the pattern of the proteins induced by African swine fever virus that react with the antisera were determined in immunoblotting assay, IP30 being the most reactive protein.  相似文献   
7.
We have analyzed the influence of the stage of ripeness on L-phenylalanine ammonia-lyase (PAL) gene expression, accumulation of anthocyanins and total phenolics, and on antioxidant activity in the skin of table grapes treated with 20% CO2 + 20% O2 + 60 % N2 for 3 or 6 d at low temperature (0 °C). The residual effect of high CO2 treatment after transfer to air was also studied. In early harvested grapes, neither the anthocyanin content nor the accumulation of VcPAL mRNA was affected by any of the CO2 treatments applied. However, in late harvested grapes, the duration of high CO2 treatment determined its effect and a 6 d treatment with CO2 sustained higher levels of total phenolics and anthocyanin accumulation, and VcPAL expression than observed in untreated late harvested grapes. The increased antioxidant capacity was correlated with the total amount of phenolics and anthocyanins. Conversely, in grapes treated for 3 d with CO2 the phenylpropanoid pathway did not appear to be induced and a relationship between antioxidant activity and anthocyanins was not observed. Thus, further studies are needed to identify the most important antioxidants in these treated fruit.  相似文献   
8.
Low serum cortisol levels in a young puppy, following adrenocorticotrophic hormone (ACTH) stimulation, were used to establish a clinical diagnosis of Addison's disease. This was likely to have been congenital although studies of adrenocortical function in close relatives showed no evidence of a genetic origin for the condition. Autoantibody to canine adrenal tissue was not present. Further investigations are necessary to establish the role of autoantibody in canine hypoadrenocorticism. The diagnosis of primary adrenocortical hypoplasia was confirmed at post mortem examination.  相似文献   
9.
This study aimed to validate the use of an automated chemiluminescent immunoassay analyser for salivary testosterone measurements in growing pigs and study how circadian pattern during daytime and stress can influence its values. The test method had intra- and inter-assay coefficient of variation lower than 10%. The method showed good linearity and recovery, and detection limits were low enough to detect salivary testosterone levels. No significant differences were observed in testosterone concentrations at different sampling time, and age and gender did not influence circadian pattern. In addition, this assay was used to quantify testosterone in two models of acute stress and, in both cases, significant increases (P< 0.01) in salivary testosterone were detected. Therefore, the automated assay system tested for porcine testosterone determinations would be suitable for its use in saliva samples and, furthermore, salivary testosterone levels could be used as a possible marker of acute stress in pigs.  相似文献   
10.
Most commonly, salivary cortisol is used in pig stress assessment, alternative salivary biomarkers are scarcely studied. Here, salivary cortisol and two alternative salivary biomarkers, haptoglobin and chromogranin A were measured in a pig stress study. Treatment pigs (n = 24) were exposed to mixing and feed deprivation, in two trials, and compared to untreated controls (n = 24). Haptoglobin differed for feed deprivation vs control. Other differences were only found within treatment. Treatment pigs had higher salivary cortisol concentrations on the mixing day (P < 0.05). Chromogranin A concentrations were increased on the day of refeeding (P < 0.05). Haptoglobin showed a similar pattern to chromogranin A. Overall correlations between the salivary biomarkers were positive. Cortisol and chromogranin A were moderately correlated (r = 0.49, P < 0.0001), correlations between other markers were weaker. The present results indicate that different types of stressors elicited different physiological stress responses in the pigs, and therefore including various salivary biomarkers in stress evaluation seems useful.  相似文献   
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