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521.
Anita Koni Arla Juma Matteo Morini Stefano Nardelli Robert Connor Xhelil Koleci 《Irish veterinary journal》2015,69(1):11
Background
Bovine tuberculosis (bTB) is an important bacterial infectious disease in Albania of concern to animal and human health; its prevalence is poorly documented.Methods
In this longitudinal study, we tested by ELISA 2661 serum samples, from 154 herds, with the aim of establishing the suitability of this approach to screen the bovine population for bTB. In a follow-on survey of 87 animals in three villages, we assessed the usefulness of the Mycobacterium bovis IDEXX ELISA (IDEXX M. bovis Antibody (Ab) Test. IDEXX Europe B.V P.O. Box 1334, 2130 EK Hoofddorp, The Netherlands) assay by comparing IDEXX results with the results of the single intradermal cervical skin test. Skin tests were performed either after or at the time of collection of blood samples, and therefore cattle were not sensitized by tuberculin before serological testing.Results
The proportion of herds in which serologically positive cattle were found was 18.2 % (95 % CI, 1.9–25.8 %) and the prevalence of seropositive cattle was 1.4 % (95 % CI, 0.8–2.1 %). In the follow-up study, two of the 87 animals reacted positively to the skin test and two produced inconclusive reactions. No overlap was found between the four animals with positive IDEXX ELISA results and the four animals with non-negative skin test results.Conclusion
The lack of agreement between the results of the two tests may reflect different elements of the immune response (humoral and cell-mediated immunity). In future, cattle should be sensitized by the intradermal injection of tuberculin 14 days prior to the collection of blood samples, which would then be tested by the Mycobacterium bovis IDEXX ELISA Test in order to determine more accurately the prevalence of infection.522.
Review on iron availability in soil: interaction of Fe minerals,plants, and microbes 总被引:1,自引:0,他引:1
Claudio Colombo Giuseppe Palumbo Ji-Zheng He Roberto Pinton Stefano Cesco 《Journal of Soils and Sediments》2014,14(3):538-548
Purpose
The rationale of this paper is to review the state of the art regarding the biotic and abiotic reactions that can influence Fe availability in soils. In soil, the management-induced change from oxic to anoxic environment results in temporal and spatial variations of redox reactions, which, in turn, affect the Fe dynamics and Fe mineral constituents. Measuring the Fe forms in organic complexes and the interaction between bacteria and Fe is a major challenge in getting a better quantitative understanding of the dynamics of Fe in complex soil ecosystems.Materials and methods
We review the existing literature on chemical and biochemical processes in soils related with the availability of Fe that influences plant nutrition. We describe Fe acquisition by plant and bacteria, and the different Fe–organic complexes in order to understand their relationships and the role of Fe in the soil carbon cycle.Results and discussion
Although total Fe is generally high in soil, the magnitude of its available fraction is generally very low and is governed by very low solubility of Fe oxides. Plants and microorganisms can have different strategies in order to improve Fe uptake including the release of organic molecules and metabolites able to form complexes with FeIII. Microorganisms appear to be highly competitive for Fe compared with plant roots. Crystalline Fe and poorly crystalline (hydro)oxides are also able to influence the carbon storage in soil.Conclusion
The solubility of crystalline Fe minerals in soil is usually very low; however, the interaction with plant, microbes, and organic substance can improve the formation of soluble FeIII complexes and increase the availability of Fe for plant growth. Microbes release siderophores and plant exudates (e.g., phytosiderophores, organic acids, and flavonoids), which can bind and solubilize the Fe present in minerals. The improved understanding of this topic can enable the identification of effective solutions for remedying Fe deficiency or, alternatively, restricting the onset of its symptoms and yield’s limitations in crops. Therefore, development and testing of new analytical techniques and an integrated approach between soil biology and soil chemistry are important prerequisites. 相似文献523.
524.
Mycorrhizal activity and diversity in a long-term organic Mediterranean agroecosystem 总被引:1,自引:0,他引:1
Stefano Bedini Luciano Avio Cristiana Sbrana Alessandra Turrini Paola Migliorini Concetta Vazzana Manuela Giovannetti 《Biology and Fertility of Soils》2013,49(7):781-790
In organic agriculture, soil fertility and productivity rely on biological processes carried out by soil microbes, which represent the key elements of agroecosystem functioning. Arbuscular mycorrhizal fungi (AMF), fundamental microorganisms for soil fertility, plant nutrition and health, may play an important role in organic agriculture by compensating for the reduced use of fertilizers and pesticides. Though, AMF activity and diversity following conversion from conventional to organic farming are poorly investigated. Here we studied AMF abundance, diversity and activity in short- and long-term organically and conventionally managed Mediterranean arable agroecosystems. Our results show that both AMF population activity, as assessed by the mycorrhizal inoculum potential (MIP) assay, the percentage of colonized root length of the field crop (maize) and glomalin-related soil protein (GRSP) content were higher in organically managed fields and increased with time since transition to organic farming. Here, we showed an increase of GRSP content in arable organic systems and a strong correlation with soil MIP values. The analysis of AMF spores showed differences among communities of the three microagroecosystems in terms of species richness and composition as suggested by a multivariate analysis. All our data indicate that AMF respond positively to the transition to organic farming by a progressive enhancement of their activity that seems independent from the species richness of the AMF communities. Our study contributes to the understanding of the effects of agricultural managements on AMF, which represent a promising tool for the implementation of sustainable agriculture. 相似文献
525.
Gabriel Otava Stefano Squicciarini Simona Marc Tijana Suici Gary William Onan Ioan Hutu Iuliu Torda Calin Mircu 《Reproduction in domestic animals》2021,56(12):1511-1518
The objective of this project was to report the effects of season and age on conception rate amongst Italian Mediterranean Buffalo subjected to an Ovsynch/Resynch (O/R) reproductive management protocol. The study utilized nulliparous (heifers), primiparous buffalo cows (PBC) and multiparous buffalo cows (MBC). The primiparous and multiparous groups were subjected to the synchronization protocol throughout the entire year, but heifers were synchronized and inseminated only during the spring/summer seasons. The conception rate obtained following the OvSynch oestrus synchronization protocol, applied during spring, was 68.4% for heifers, 83.3% for PBC and 67.7% for MBC. The overall total conception rates following the complete O/R protocol were 84.27%, 94.4% and 79%. Conception rates achieved during summer were heifers 52%, PBC 47.2% and MBC 49%, whilst overall conception rates following the full O/R protocol were 72%, 69.8% and 58.2% respectively. In the autumn seasons, PBC conceived 58.9% and MBC 52.1% following initial Ovsynch, which improved to total overall conception rates of 87.5% and 78.7% following the full O/R protocol. Similarly, in the winter season, PBC experienced a conception rate of 47.5% following Ovsynch and 72.5% after a follow-up Resynch. MBC experienced 60.0% and 74.4% conception following Ovsynch and full O/R, respectively, during winter. Total conception rates during all seasons were quite acceptable following the O/R protocol. There was a significant decrease from spring to summer in conception rate for all parity groups, but heifers were not a severely affected as older buffalo cows. This finding agrees with that of other investigators indicating that heifer fertility is not as negatively impacted by long photoperiod and higher ambient temperature as that of older animals. The O/R protocol as utilized in this study is an effective means of reproductive management for dairy buffalo cows and is effective for improving fertility during out-of-season breeding. 相似文献
526.
Stefano Monaco Dario Sacco Teresa Borda Carlo Grignani 《Biology and Fertility of Soils》2010,46(2):179-184
We evaluated the in situ net nitrogen (N) mineralization in a soil cropped to maize and fertilized for 11 years with cattle
slurry or farmyard manure, both common on livestock farms of the Po River valley in Northern Italy. The net N mineralization
of the tilled soil layer was measured in six consecutive incubation periods after manure application, for a total of 12 weeks,
using the polyethylene buried bags technique. Results showed that net N mineralization was followed by N immobilization and
finally, by mineralization whose rate increase until maize flowering. On average, net N mineralization was 70.4 kg N ha−1, with the majority being released during the last measurement period. The time and extent of net N mineralization and plant
N uptakes were not affected by fresh manure application. Instead, the effect of past management increased the maximum net
N mineralization rate obtained with farmyard manure. The buried bag technique probably underestimates the total amount of
mineralized N available for crop growth because it excludes the presence of the plant. 相似文献
527.
Debora Tura Carmen Gigliotti Stefano Pedò Osvaldo Failla Daniele Bassi Arnaldo Serraiocco 《Scientia Horticulturae》2007
Oxidation stability is an important property of olive oil quality and is affected by different antioxidant compounds whose levels may be influenced by cultivar, year and place of production. Polyphenols, tocopherols, carotenoids, chlorophylls and fatty acids levels were correlated to oxidative stability in olive oils from three experiments: cultivar influence (18 cultivars assessed for 4 years in the same place); environmental influence by mesoclimatic (4 cultivars from 17 sites in a single region for 4 years) and macroclimate conditions (3 cultivars from 3 different regions for 3 years). Total polyphenols and saturated on polyunsaturated fatty acids ratio were shown to be the major factors in oil antioxidant stability, according to multivariate regression models. Among the surveyed cultivars, oils from ‘Leccino’ and from three ‘local’, minor cultivars (‘Miniol’, ‘Regina’ and ‘Rossanello’) resulted in higher oxidative stability and oils from cultivars grown in Tuscany (central Italy) showed the highest oxidative stability by comparison with northern and southern regions. 相似文献
528.
Sara Belluco Giuseppe Marano Thibaut Lurier Giancarlo Avallone Chiara Brachelente Stefano Di Palma Roberta Rasotto Kerstin Baiker Andreas Beineke Anna Oevermann Frauke Seehusen Fabiano José Ferreira de Sant'Ana Patrizia Boracchi Martí Pumarola Maria Teresa Mandara 《Veterinary and comparative oncology》2023,21(4):685-699
Canine meningiomas are currently graded using the human grading system. Recently published guidelines have adapted the human grading system for use in dogs. The goal of this study was to validate the new guidelines for canine meningiomas. To evaluate the inter-observer agreement, 5 veterinary surgical pathologists graded 158 canine meningiomas following the human grading system alone or with the new guidelines. The inter-observer agreement for histologic grade and each of the grading criteria (mitotic grade, invasion, spontaneous necrosis, macronucleoli, small cells, hypercellularity, pattern loss and anaplasia) was evaluated using the Fleiss kappa index. The diagnostic accuracy (sensitivity and specificity) was assessed by comparing the diagnoses obtained with the 2 grading systems with a consensus grade (considered the reference classification). The consensus histologic grade was obtained by agreement between 4 experienced veterinary neuropathologists following the guidelines. Compared with the human grading alone, the canine-specific guidelines increased the inter-observer agreement for: histologic grade (κ = 0.52); invasion (κ = 0.67); necrosis (κ = 0.62); small cells (κ = 0.36); pattern loss (κ = 0.49) and anaplasia (κ = 0.55). Mitotic grade agreement remained substantial (κ = 0.63). The guidelines improved the sensitivity in identifying grade 1 (95.6%) and the specificity in identifying grade 2 (96.2%) meningiomas. In conclusion, the new grading guidelines for canine meningiomas are associated with an overall improvement in the inter-observer agreement and higher diagnostic accuracy in diagnosing grade 1 and grade 2 meningiomas. 相似文献