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To contribute to the insight into the worldwide population structure of Toxoplasma gondii, we genetically characterized a total of eight strains isolated from intermediate hosts including humans, sheep and pigeons in Serbia. Although parasite DNA was detected in 28.2% (60/213) of the human samples from 162 patients serologically suspected of active toxoplasmosis, as well as in 5/7 seropositive pigeons and in 2/12 seropositive sheep examined, multilocus PCR-RFLP genotyping, using SAG1, 5′SAG2, 3′SAG2, GRA6, 5′GRA7 and 3′GRA7 as markers, was successful in only four human isolates (of which one was isolated from both the bronchoalveolar lavage fluid and blood samples of a single patient), one sheep and three pigeons. Of the eight isolates, five were type II (62.5%), one was type III, one was atypical, and one had a type I allele at GRA6 as the single locus genotyped. Although type II, as elsewhere in Europe, predominated, these results may suggest a higher genetic diversity of T. gondii in Serbia, reflecting local environmental contamination and also the geographical position of the country in South-East Europe.  相似文献   
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Four laboratory populations, each consisting of flies homozygous for a wild second chromosome, were maintained in population cages. Three of them were initially characterized by low fecundity of the females; the fourth was a control. After 15 months, in all three populations with low fecundity this character was much improved; two of them, have reached the control level. The changes observed were presumably due to mutation and selection under highly competitive conditions.  相似文献   
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Between 2012 and 2014, we tested the efficacy of different synthetic attractants for the purpose of massive trapping of common European cockchafer adults (Melolontha melolontha). The research took place in three different locations in Slovenia (Otlica, ?rni Vrh nad Idrijo, Cesta nad Ajdov??ino) during flight periods of adult beetles. In the period 2013–2014, we used, on the basis of the preliminary test results (2012), the following chemicals: toluquinone, cis–3–hexen–1-ol, ethyl acetate, toluquinone?+?cis–3 hexen–1-ol, and ethanol as a control. M. melolontha adults were most abundant in the location ?rni Vrh nad Idrijo; the traps in this location caught 18 times more of them than those in the first location and more than six times more than those in the third location. Male insects accounted for 73 to 87% of the trapped specimens. We confirmed the highest efficiency of cis–3–hexen–1-ol in 2013 (43.25?±?0.08 males/trap), as well as in 2014 (15.00?±?0.14 males/trap). On the basis of the trapped adult common European cockchafers and the simple economic analysis of applying different synthetic substances for attracting them, we found that independent application of cis-3-hexen-1-ol is the most efficient and cost-effective option for attracting the studied insect pest. Consequently, we recommend it as an attractant in the traps for massive trapping of adult common European cockchafers.  相似文献   
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To identify areas of risk for canine-related zoonoses in Serbia, the aim of this study was to provide baseline knowledge about intestinal parasites in 151 dogs (65 household pets, 75 stray and 11 military working dogs) from Belgrade. The following parasites, with their respective prevalences, were detected: Giardia duodenalis (14.6%), Ancylostomatidae (24.5%), Toxocara canis (30.5%), Trichuris vulpis (47.0%) and Taenia-type helminths (6.6%). Of all examined dogs, 75.5% (114/151) were found to harbour at least one parasite species. Of these, mixed infections with up to four species per dog occurred in 44.7% (51/114). Infections with all detected species were significantly higher (p < 0.05) in military working (100%) and stray dogs (93.3%) versus household pets (50.8%). Among all parasites, agents with zoonotic potential including Giardia, Ancylostomatidae and Toxocara were detected in 58.3% (88/151) of all examined dogs with a significant difference (p < 0.05) among the subgroups (100%, 62.7% and 46.2% for military working dogs, stray dogs and household pets, respectively). The high prevalence of zoonotic parasites registered in the dog population from a highly urban area in south-eastern Europe indicates a potential risk to human health. Thus, veterinarians should play an important role in helping to prevent or minimise zoonotic transmission.  相似文献   
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Use of varieties bred under organic conditions is essential in order to minimize the yield gap between organic and conventional agriculture. The aim of this study was to analyse research publications related to the topic ‘organic plant breeding’ from the Web of Science database using bibliometric science mapping and visualization tools. The number of analysed documents in the bibliographic dataset was 204 from the 53 sources. The overall trend in the organic plant breeding literature showed that the number of publications increased during the observed time-span. We found that in total, 65 countries and 337 institutions are active in the field of organic plant breeding with a high degree of international collaboration. The top five countries according to the number of publications were the United States, Italy, Germany, France, and Canada, while the most active institutions were Wageningen University, Iowa State University, University of Alberta, University of Copenhagen, and University of Hohenheim. All keywords from the organic plant breeding research in the agronomy category were separated into seven clusters for different research topics. Although there is evident progress viewed through the increased trend in the number of publications, organic plant breeding needs further expansion and development. This is especially through the implementation of novel plant breeding techniques and methods aiming to improve traits that are highly specific to organic conditions.  相似文献   
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Current agricultural practice favours winter cover crops, which can not only optimize N management in field crop rotation; but also affect subsequent crops. Three field experiments were carried out in Eastern Slovenia to examine the effects of Italian ryegrass (Lolium multiflorum Lam.), winter rape (Brassica napus ssp.oleifera (Metzg.) Sinsk), subclover (Trifolium subterraneum L.), and crimson clover (Trifolium incarnatum L.) as winter cover crops on the mineral N (Nmin) content of soil and on the yield and N content of subsequent maize (Zea mays L.), fertilized with 120 kg N ha−1. Italian ryegrass and winter rape decreased soil Nmin contents before winter and in spring more than both clovers. In contrast, clovers accumulated significantly higher amounts of N in organic matter and had lower C/N ratios than winter rape and especially Italian ryegrass. In comparison to the control (bare fallow without cover crop), clovers increased the whole above ground maize dry matter yield, maize grain yield and N contents in whole above ground plants and in grain. The yields and N contents of maize following winter rape were on the same level as the control, while yields and N contents of maize following Italian ryegrass were, in two of the experiments, at the same level as the control. The effects of Italian ryegrass on the maize as subsequent crop in the third experiment were markedly negative. Maize in the control treatment exploited N much more efficiently than in treatments with cover crops. Therefore, cover crop N management should be improved, especially with a view to optimizing the timing of net N mineralization in accordance with the N demands of the subsequent crop.  相似文献   
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This trial was designed in order to evaluate the incidence of subacute rumen acidosis (SARA) during early lactation and to investigate the possibilities for its prevention by use of a buffering mineral mixture. On the beginning of the trial it was found that the pH value of rumen fluid in 4 animals was lower than normal (pH < 6.0) and that 20% of animals have had SARA. The control and the experimental group of cows were fed the same meal with exception of concentrated feed which in the experimental group contained the mineral mix with buffering activity in amount of 1%. Continuous addition of buffering mineral mixture in the amount of 1% in concentrated feed for early lactation cows successfully prevents SARA formation and leads to increased milk production, as well as increased milk fat and protein content.  相似文献   
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ABSTRACT: A seroepizootiological study of Toxoplasma gondii infection involving a total of 488 slaughter pigs (468 market-weight pigs and 20 sows) in the Belgrade area, also included examination of the presence of T. gondii in the blood. Blood sampled at the slaughter line was examined for specific antibodies by modified direct agglutination, and blood clots of those seropositive at titres of 1:50-1:12800 were bioassayed in mice. The overall seroprevalence was 9.2%, significantly higher (p = 0.0063) in sows (30.0%) than in market-weight pigs (8.3%). Amongst the 22 bioassays performed, a total of 16 (72.7%) were positive, by observation of T. gondii cysts (12), seropositivity (7, including 3 in which cysts were not detected), and/or detection of T. gondii DNA by real-time PCR (12, including one otherwise negative). The positive bioassays originated from the blood of 12 market-weight pigs and 4 sows. Despite a general increase in the rate of demonstration of T. gondii with the increase in the specific antibody level, the association was not significant (p = 0.101). The risk of infection was 41-fold increased in sows vs market-weight pigs, and 15-fold in pigs from smallholders' finishing type farms vs those from large farrow-to-finish farms. The presence of viable T. gondii in a proportion of the samples indicates that some of the pigs had an active parasitaemia at the time of slaughter, which, along with the seroprevalence established, points to a potential source of human infection in Serbia. This is the first report on parasitaemia in naturally infected swine.  相似文献   
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