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European Journal of Plant Pathology - Sorghum anthracnose caused by the fungal pathogen Colletotrichum sublineolum, is one of the most economically important diseases of sorghum globally and in...  相似文献   
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The potato leafroll virus (PLRV) P0 protein (P0PL) is a suppressor of RNA silencing. In this study, we showed that P0 protein from an Argentinian isolate of PLRV (P0PL-Ar) has an additional activity not described for other PLRV or P0 proteins from poleroviruses. Besides reporting that P0PL-Ar displays both local and systemic silencing suppressor activity, we demonstrated, for the first time, that P0PL-Ar impedes accumulation of dsRNA-derived siRNAs. We also showed that P0PL-Ar interacts with Solanum tuberosum SKP1 orthologue (StSKP1) and triggers destabilization of ARGONAUTE 1 (AGO1) and that these actions are mediated by the F-box-like domain. A mutant in the GW/WG motif within the P0PL-Ar F-box-like motif lost the suppression activity, the interaction with StSKP1 and abolished AGO1 decay. Interestingly, a mutant in the L76/P77 residues within the P0PL-Ar F-box-like motif, which lost the suppression activity and the interaction with StSKP1, retained the capacity to enable AGO1 decay. Thus, unlike other P0 proteins of previously characterized poleroviruses, P0PL-Ar seems to have a dual activity, according to the findings of this study. This protein would act at both an upstream and a downstream step of the RNA silencing pathway: upstream of Dicer-like enzyme (DCL)-mediated primary siRNA production and downstream at the RNA-induced silencing complex (RISC) complex level. Our results contribute to the understanding of the different ways PLRV P0 proteins function as silencing suppressors.  相似文献   
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Bovine tuberculosis is a contagious and zoonotic disease of animals and humans. In Europe, the number of reported cases of tuberculosis has decreased. Equidae are relatively rarely infected even in endemic areas. The presented report describes a case of chronic Mycobacterium bovis tuberculosis in a 30-year-old female donkey. The donkey initially presented with persistent lymphadenopathy; however, as the disease progressed, weight loss became apparent. To the authors' knowledge, this is the second confirmed case of tuberculosis in a donkey in Europe.  相似文献   
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The purpose of this work was to determine a radiographic standard of normality for lateral and medial ungulae in 3‐year‐old bovine females of the Nellore breed. Twenty‐six cows underwent radiographic exposure of the medial and lateral ungulae of the hindlimbs and forelimbs; abaxioaxial projections were used. The images were analyzed; distances were measured between the dorsal surface of the distal phalanx and the surface of the hoof capsule. The two angles formed, i.e., an angle between the dorsal surface of the distal phalanx and a line parallel to the sole (inner), and an angle between the dorsal surface of the hoof and a line parallel to the sole (outer), were also recorded. The results suggested a standard of normality for the proximal, middle and distal distances of the ungulae of the forelimbs: 0.96 ± 0.12 cm. For the measurement of hindlimbs, except for the distal distances of the side ungulae, the suggested value was 1.02 ± 0.14 cm; for the distal measurement of the lateral ungulae of the hindlimbs, the value was 1.09 ± 0.12 cm. For inner and outer angles, the values were 36.45° ± 4.4° for the medial ungulae of the forelimbs and 42.50° ± 3.8° for other ungulae of the forelimbs and hindlimbs (standard deviations of the values suggested for the angles should be used as variations between different animals, limbs and ungulae; they should not be used between angles of the same ungula).  相似文献   
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Objective of this review paper is the appraisal of predisposing factors for bacterial mastitis in ewes. Factors that predispose ewes to mastitis can be classified into non‐animal‐related factors (environmental and climatological factors, housing, nutrition, milking practices) and animal‐related factors (anatomic, genetic, litter size—ethological factors, number and stage of lactation period, health problems). There are clear management—environment—animal interactions in mastitis development in ewes, which underline its multifactorial nature. Research and studies regarding risk factors are important, in order to develop strategies for their elimination, control or correction. Control measures for bacterial mastitis, which attempt to eliminate predisposing factors for infection, can thus be developed and implemented.  相似文献   
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Background: In order to discover new strategies to replace antibiotics in the post-antibiotic era in meat-type chicken production, two new synbiotics were tested:(Lactobacillus salivarius IBB3154 plus galactooligosaccharide(Syn1) and Lactobacillus plantarum IBB3036 plus raffinose family oligosaccharides(Syn2).Methods: The synbiotics were administered via syringe, using a special automatic system, into the egg air chamber of Cobb 500 broiler chicks on the 12 thday of egg incubation(2 mg of prebiotics + 105 cfu bacteria per egg).Hatched roosters(total 2,400) were reared on an experimental farm, kept in pens(75 animals per pen), with free access to feed and water. After 42 d animals were slaughtered. Blood serum, pancreas, duodenum and duodenum content were collected.Results: Syn2 increased trypsin activity by 2.5-fold in the pancreas and 1.5-fold in the duodenal content. In the duodenum content, Syn2 resulted in ca 30% elevation in lipase activity and 70% reduction in amylase activity.Syn1 and Syn2 strongly decreased expression of m RNA for GLP-1 and GIP in the duodenum and for GLP-1 receptors in the pancreas. Simultaneously, concentrations of the incretins significantly diminished in the blood serum(P 0.05). The decreased expression of incretins coincides with changed activity of digestive enzymes in the pancreas and in the duodenal content. The results indicate that incretins are involved in the action of Syn1 and Syn2 or that they may even be their target. No changes were observed in key hormones regulating metabolism(insulin, glucagon, corticosterone, thyroid hormones, and leptin) or in metabolic indices(glucose,NEFA, triglycerides, cholesterol). Additionally, synbiotics did not cause significant changes in the activities of alanine and aspartate aminotransferases in broiler chickens. Simultaneously, the activity of alkaline phosphatase and gamma glutamyl transferase diminished after Syn2 and Syn1, respectively.Conclusion: The selected synbiotics may be used as in ovo additives for broiler chickens, and Syn2 seems to improve their potential digestive proteolytic and lipolytic ability. Our results suggest that synbiotics can be directly or indirectly involved in incretin secretion and reception.  相似文献   
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