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Precision Agriculture - Farm management information system (FMIS) is an important element of precision agriculture to support the decision making process in the agricultural business. Developing...  相似文献   
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The present study investigated the effects of dietary trans‐cinnamic acid (TrCin) on growth performance, biochemical composition, fatty acid composition, blood biochemistry, antioxidant status, digestive enzyme and liver antioxidant gene (EF1α, SOD1, SOD2, CAT, GPX1, GPX4, GR and GST) expression responses of rainbow trout, Oncorhynchus mykiss. Five experimental groups of fish with mean weights of 17.49 ± 0.08 g were used in the study; four of them were fed with TrCin‐supplemented diets (0.25 g/kg TrCin25, 0.50 g/kg TrCin50, 0.75 g/kg TrCin75 and 1.50 g/kg TrCin150), whereas an additive‐free basal diet served as the control (Cntr). At the end of the 60‐day feeding trial, the growth performance, biochemical composition and fatty acid composition were similar for all experimental groups. A decrease was observed in intestinal and stomach pH, serum triglyceride and AST, ALT, LDH and ALP levels in fish fed with especially 0.50 g/kg TrCin‐supplemented diet. Moreover, dietary TrCin especially at 0.50 g/kg incorporation level significantly increased the serum SOD and liver SOD2, CAT, GST, GPX1, GPX4 and GR gene expression responses. As a conclusion, feeding rainbow trout for a period of 60 days with a diet containing 0.50 g/kg TrCin might be sufficiently enough to improve the levels of antioxidant enzymes and health status in fish.  相似文献   
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The essential oils of aerial parts of Achillea gypsicola Hub.-Mor., Hypericum scabrum L., Satureja hortensis L., and Origanum acutidens (Hand.-Mazz.) Letswaart were analyzed in this study by GC and GC–MS and their oils were tested for toxicity against broadbean weevil (Bruchus dentipes). A. gypsicola oil contained camphor (40.17%), 1,8-cineole (22.01%), piperitone (11.29%), borneol (9.50%) and α-terpineol (1.56%) as major components. A total of 74 components were identified by GC–MS in H. scabrum oil, including α-pinene (9.26%), terpinen-4-ol (5.12%), camphor (5.94%), δ-cadinene (4.52%), pulegone (4.45%), γ-muurolene (4.12%), pinocarvone (3.97%) and β-caryophyllene (3.42%) as predominant components. The essential oils of O. acutidens and S. hortensis were characterized by high contents of carvacrol (86.99% and 55.74%), γ-terpinene (0.71% and 20.94%), p-cymene (1.95% and 12.30%), α-terpinene (0.13% and 2.04%) and β-caryophyllene (1.30% and 1.08%). All of the essential oils were toxic to adults of B. dentipes and insect mortality increased with increasing concentration of each oil. The oils (20 μl dose) brought about 100% mortality in 36 h. Although desirable insecticidal activities against the pest were achieved with the oils from all four plant species, S. hortensis and O. acutidens oils were more effective, particularly after 6 h of treatment. The current results concluded that the essential oils, in particular O. acutidens and S. hortensis oils, may be used as potential botanical insecticides against B. dentipes.  相似文献   
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In this study, antimicrobial films were developed against Campylobacter jejuni by incorporation of gallic acid (GA) into zein-based films. The zein and zein-wax composite films containing GA between 2.5 and 10 mg/cm(2) were effective on different C. jejuni strains in a concentration-dependent manner. Zein and zein-wax composite films showed different release profiles in distilled water but quite similar release profiles at solid agar medium. Depending on incorporated GA concentration, 60-80% of GA released from the films, while the remaining GA was bound or trapped by film matrix. The GA at 2.5 and 5 mg/cm(2) caused a considerable increase in elongation (57-280%) of all zein films and eliminated their classical flexibility problems. The zein-wax composite films were less flexible than zein films, but the films showed similar tensile strengths and Young's modulus. Scanning electron microscopy indicated different morphologies of zein and zein-wax composite films. This study clearly showed the good potential of zein and GA to develop flexible antimicrobial films against C. jejuni.  相似文献   
5.
The chemical composition of essential oils isolated by hydrodistillation from the aerial parts of Achillea gypsicola Hub-Mor., Achillea biebersteinii Afan. and n-hexane extracts obtained from the flowers of A. gypsicola and A. biebersteinii Afan. was analyzed by GC and GC–MS. Camphor (40.17–23.56%, respectively), 1,8-cineole (22.01–38.09%, respectively), piperitone (11.29–0.37%, respectively), borneol (9.50–5.88%, respectively) and α-terpineol (1.56–5.15%, respectively) were found to be the main constituents in A. gypsicola and A. biebersteinii essential oils. Furthermore, hexane extracts of A. gypsicola and A. biebersteinii consist of mainly camphor (37.78–27.88%, respectively), 1,8-cineole (13.43–24.78%, respectively), piperitone (15.57%-tr, respectively), n-eicosane (1.61–9.68%, respectively), n-heneicosane (2.56–9.55%, respectively), n-tricosane (3.46–10.04%, respectively), linoleic acid (6.19–3.17%, respectively) and borneol (5.66–5.58%, respectively). Although the oils and extracts were characterized relatively by high content of oxygenated monoterpenes, hexane extracts of the plant samples relatively rich in n-alkanes, fatty acids and fatty acid esters as compared with the oil. The oils and hexane extracts were also tested against 12 phytopathogenic fungi and the oils found to be more toxic as compared with hexane extracts of the plant samples. A. gypsicola oil only did not inhibit the growth of Fusarium graminearum. The extracts also strongly increased the growth of Fusarium equiseti and F. graminearum. Therefore, the antifungal activity of the oils can be attributed to their relatively high content of oxygenated monoterpenes. The results of herbicidal assays of the essential oils and hexane extracts of the plant samples against five important weeds in cultivated areas, Amaranthus retroflexus L., Chenopodium album L., Cirsium arvense L. (Scop.), Lactuca serriola L. and Rumex crispus L. showed that, in particular, the oils had inhibitory effects on the seed germination and seedling growth of A. retroflexus, C. arvense and L. serriola. The hexane extracts also showed lower herbicidal effect against the weeds in comparison to that of the oils. The findings of the present study suggest that the essential oils have a potential to be used as herbicide as well as fungicide.  相似文献   
6.

The collection of farmed fish samples and subsequent diagnosis of microbial pathogens can be difficult and time-consuming procedure under field conditions. Correct diagnosis and identification of bacterial diseases agents (Yersinia ruckeri, Flavobacterium psychrophilum, Lactococcus garvieae, and Vagococcus salmoninarum) are crucial for the effective treatment. In this study, the feasibility of using FTA® card (Flinders Technology Associates filter papers) for sampling infected rainbow trout (Oncorhynchus mykiss) tissues and significantly accelerated the molecular diagnosis of enteric redmouth disease, rainbow trout fry syndrome, bacterial coldwater disease, lactococcosis associated with fatal hemorrhagic septicemia, and vagococcosis were evaluated. We also examined and compared a practical and reliable extraction obtained from immobilized DNA on FTA® card with one commonly used commercial kit to diagnose bacterial pathogens in fish tissues. Results proved that the active working time of extracting DNA from FTA® card is requiring only 30 min and the cost is less than USA $ 0.5 for each eluted sample. A total of hundred extracted DNA from tissues on FTA® card were tested and showed successful PCR amplification of the aroA, murG, pLG, and pSa1 genes. In conclusion, our finding indicates FTA® card as an appropriate tool for the simple collection, easy transfer, and stored at room temperature without contamination and retrieval of high-quality DNA for rapid molecular diagnosis of bacterial fish pathogens without isolation and culture.

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7.
The effect of high hydrostatic pressure application on fetal bovine serum components and the model microorganism (Bovine Viral Diarrheavirus type 1 NADL strain) was studied at 132 and 220 MPa pressure for 5 min at 25°C. Protein secondary structures were found to be unaffected by an artificial neural network application on the amide I region for both untreated and HHP treated samples. FTIR spectroscopy study of both the HHP-treated and control samples revealed changes in the intensity of some bands in the finger-print region (1500-900 cm(-1)) originating mainly from lipids which are thought to result from changes in the lipoprotein structure. The virus strain lost its infectivity completely after 220 MPa HHP treatments. These results indicate that HHP can be successfully used for inactivation of pestiviruses while leaving structural and functional properties of serum and serum products unaffected.  相似文献   
8.
Dichelobacter nodosus, a Gram-negative strict anaerobe, is the essential causative agent of ovine footrot. Despite its worldwide presence, the disease has significant economic impact in those sheep-farming countries with a temperate climate and moderate to high rainfall, such as New Zealand (NZ) and Australia. In this study, we aimed to isolate, identify, and characterize as many D. nodosus strains as possible from NZ farms by using polymerase chain reaction (PCR)-based technology. Understanding the virulence of this bacterium and showing extensive genomic variation in the fimbrial subunit gene (fimA) in different D. nodosus strains was very important to produce serogroup specific and effective vaccine for NZ. More than 100 footrot samples were collected from four different farming regions in NZ. Thousands of primary plates were cultured anaerobically and examined with Gram-staining in order to detect single colonies of D. nodosus. Approximately 500 plates that had potential D. nodosus colonies were subcultured several times to eliminate contaminating colonies until single colonies were obtained. Variable and a part of the conserved regions of the fimbrial subunit gene (fimA) were amplified directly from bacterial DNA extracted from footrot lesions and also from cultured NZ D. nodosus isolates, using the polymerase chain reaction. Different fimA amplimers were analyzed by DNA sequencing. On the basis of DNA sequence analysis, 16 new D. nodosus isolates belonging to eight different serogroups were identified from NZ. These new D. nodosus fimA sequences from NZ were different to previously reported strains and strains used in a commercial vaccine.  相似文献   
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Dichelobacter nodosus is the causative agent of ovine footrot and the type-IV fimbriae on this bacterium are essential for maintaining its virulence. In this study, we reveal that these fimbriae are glycosylated. This was demonstrated in several ways: by the detection of carbohydrate on fimbrial protein using periodic acid Schiff reagent (PAS) staining of SDS-PAGE gels and by demonstrating enzymatic deglycosylation and by analysis of the amino acid sequences derived from the fimA gene, whereby the gene from isolates of D. nodosus that appeared to be glycosylated had potential glycosylation sites both inside and outside of the variable region of fimA. The results would also explain the observation that the calculated molecular weight of fimA from some D. nodosus serotypes does not correlate with the apparent size determined from electrophoretic mobility.  相似文献   
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