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101.
Cárdenas Liliana Cañas-Álvarez Jhon J. Vázquez Ana Boixadera Ester Casal Jordi 《Tropical animal health and production》2019,51(2):383-388
Tropical Animal Health and Production - Bovine brucellosis is a zoonotic disease that causes great economic losses. The disease is endemic in Colombia and animal movements from infected herds carry... 相似文献
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Effects of pure plant secondary metabolites on methane production,rumen fermentation and rumen bacteria populations in vitro 下载免费PDF全文
M. Joch J. Mrázek E. Skřivanová L. Čermák M. Marounek 《Journal of animal physiology and animal nutrition》2018,102(4):869-881
In this study, the effects of seven pure plant secondary metabolites (PSM s) on rumen fermentation, methane (CH4) production and rumen bacterial community composition were determined. Two in vitro trials were conducted. In trial 1, nine concentrations of 8‐hydroxyquinoline, α‐ terpineol, camphor, bornyl acetate, α‐ pinene, thymoquinone and thymol were incubated on separate days using in vitro 24‐hr batch incubations. All compounds tested demonstrated the ability to alter rumen fermentation parameters and decrease CH4 production. However, effective concentrations differed among individual PSM s. The lowest concentrations that reduced (p < .05) CH4 production were as follows: 8 mg/L of 8‐hydroxyquinoline, 120 mg/L of thymoquinone, 240 mg/L of thymol and 480 mg/L of α‐ terpineol, camphor, bornyl acetate and α‐ pinene. These concentrations were selected for use in trial 2. In trial 2, PSM s were incubated in one run. Methane was decreased (p < .05) by all PSM s at selected concentrations. However, only 8‐hydroxyquinoline, bornyl acetate and thymoquinone decreased (p < .05) CH4 relative to volatile fatty acids (VFA s). Based on denaturing gradient gel electrophoresis analysis, different PSM s changed the composition of bacterial communities to different extents. As revealed by Ion Torrent sequencing, the effects of PSM s on relative abundance were most pronounced in the predominant families, especially in Lachnospiraceae , Succinivibrionaceae , Prevotellaceae , unclassified Clostridiales and Ruminococcaceae . The CH 4 production was correlated negatively (?.72; p < .05) with relative abundance of Succinivibrionaceae and positively with relative abundance of Ruminococcaceae (.86; p < .05). In summary, this study identified three pure PSM s (8hydroxyquinoline, bornyl acetate and thymoquinone) with potentially promising effects on rumen CH4 production. The PSM s tested in this study demonstrated considerable impact on rumen bacterial communities even at the lowest concentrations that decreased CH4 production. The findings from this study may help to elucidate how PSM s affect rumen bacterial fermentation. 相似文献
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Črtomir Rozman Aleksandar Maksimović Adis Puška Zoan Grgić Karmen Pažek Boris Prevolšek Ferhat Ćejvanović 《Erwerbs-Obstbau》2017,59(3):235-243
The success or failure of an investment project in fruit production also depends on the selection of the fruit species and variety. When selecting the variety for the creation of a new orchard it is necessary to perform the synthesis of different data and to look at all aspects of the investment. This paper presents the application of DEX multi-criteria decision making. The model was applied on 7 varieties of plum from the western Balkans region that were assessed by experts from “The association of agricultural economists of Western Balkans” using the Delphi method.By applying this model it has been shown that the ’Stanley’ is the most suitable for starting a new orchard while the varieties ’?a?anska ljepotica’ and ’?a?anska rodna’ are also very suitable for starting new fruit orchards and they have also received the value attribute “very acceptable”.Using this model all strong and weak sides of the observed plum variety were shown. For the final selection it is necessary to conduct research at a specific micro location where all characteristics of that area would also be taken into consideration. 相似文献
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Dinka Grubišić Ljerka Oštrec Tanja Gotlin Čuljak Sylvia Blümel 《Journal of pest science》2007,80(1):21-27
Potato cyst nematodes (PCN) Globodera rostochiensis (Wollenweber, 1923) Behrens, 1975 and Globodera pallida (Stone, 1973) Behrens, 1975 are the most troublesome pests of potatoes worldwide. Since 1968 there have been no investigations
of the presence of PCN in ware potato lands in Croatia although these pests were recognised as an A1 plant-health quarantine
species. After the first discovery of G. rostochiensis in the locality of Belica (Medjimurska County) in 2001, intensive monitoring of the distribution of PCN in Croatia started.
In 2001 G. rostochiensis was detected in 55% of soil samples taken in ware potato lands. In 2002 G. rostochiensis was detected in 4.1% of soil samples and in 0.08% of soil samples in mixed populations with G. pallida. The pathotype Ro1 was found in all tested populations and Ro1 and Pa 2/3 were detected in populations from localities Vidovec,
Ivanovec and Sivice. In 2003 G. rostochiensis was detected in 1.03% of soil samples, and also in 12.8% of soil samples collected in 2004. In 2003 cysts of G. rostochiensis were detected in several seed potato fields. These results indicate the urgent need for the application of further control
measures to determine the presence and distribution of PCN in ware and seed potato lands in Croatia, in order to prevent the
spread of PCN to non-infested areas. Integrated management strategies, neglected until 2001, have now been implemented and
will prevent the build-up of infestation and replace the previous practices of monoculture, the use of short rotations and
growing susceptible cultivars. 相似文献
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Isabella Børja Jan Svĕtlík Valeriy Nadezhdin Jan Čermák Sabine Rosner Nadezhda Nadezhdina 《Scandinavian Journal of Forest Research》2016,31(5):450-457
Top dieback of Norway spruce (Picea abies), triggered by drought in 2004–2006, has been observed in Southeast Norway and trees died within four years after appearance of the first symptoms. The aim of our study was to use sap flux measurements as a diagnostic method for assessment of tree vitality. We used the heat field deformation method to monitor the sap flux density (SFD) in four pairs of healthy and declining trees in situ. To provide retrospective information on hydraulic performance of the trees we took samples for wood anatomical analysis. After felling the trees we used the modified differential translucence method (MDT) as a proxy for the SFD measurements. Healthy trees had three times higher SFD values as declining trees. In some healthy trees we detected decreasing SFD with time. The MDT method agreed with the SFD measurements. In conclusion, we detected sap flux dysfunction in declining trees and showed that the SFD reduction may occur during a short period, prior to occurrence of any visual symptoms. We suggest incorporating the SFD measurements into the repertoire of diagnostic tools in forest pathology. 相似文献