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排序方式: 共有193条查询结果,搜索用时 15 毫秒
71.
《Communications in Soil Science and Plant Analysis》2012,43(1-2):168-176
Abstract Thalli of the lichens Pseudevernia furfuracea, Usnea longissima, Lobaria pulmonaria, and Peltigera praetextata were taken from unpolluted areas and transplanted to a downtown site in Erzurum, Turkey. Heavy metals copper (Cu), chromium (Cr), zinc (Zn), lead (Pb), nickel (Ni), and iron (Fe) were measured after an 8 month exposure period. Changes in the heavy metal concentrations were observed during the exposure period in lichen species and in both locations. Heavy metal concentrations were significantly higher in Peltigera praetextata than the other species at the location nearest to the junction crossroads. Peltigera praetextata may be considered a good indicator. These results can be attributed to the effect of atmospheric pollutants on the transplanted lichens. 相似文献
72.
A prospective cohort study was conducted in the Brittany region to identify the risk factors related to foot-pad dermatitis (considered an indicator of animal well-being) in chicken and turkey broilers reared under commercial conditions. Factors related to the shed, equipment, litter management and stocking density were recorded; the dependent variable was the prevalence of lesions observed on the slaughterhouse chain. Lesions were scored from 0 (no lesion) to 3 (severe lesion). Our survey lasted from May 1999 to October 2000. Fifty flocks of chicken broilers (15 farms), 27 flocks of female turkey broilers (21 farms) and 41 flocks of male turkey broilers (27 farms) were surveyed. In chicken broilers, 10% of flocks were of high quality (80% of birds with score 0) and this was related to the use of concrete floors with a thin layer of wood shavings. In turkey broilers, 48% of female and 46% of male flocks were of bad quality (>10% of birds with score 3). A poor fan ventilation system (<150 m3/h/kg) was a significant risk factor. Turkey flocks of high quality were not observed. Stocking density had no influence on the prevalence of foot-pad dermatitis. We concluded that it is possible under high commercial stocking densities to have flocks with a low prevalence of foot-pad dermatitis in chicken broilers, whereas it is not in turkey broilers. Hence in chicken broilers, implementing a monitoring system based on the observation of foot-pad dermatitis prevalence at slaughter appears to be more appropriate than to legislate stocking density. In turkey broilers, it would probably be necessary either to reduce the stocking density drastically or to investigate new systems of floor drainage. 相似文献
73.
J. Danguy des Déserts R. H. Davies K. Vaughan I. McLaren P. Canning A. Wintrip D. Mueller‐Doblies J. J. Carrique‐Mas 《Zoonoses and public health》2011,58(3):200-208
Salmonella is, after Campylobacter, the most reported zoonotic pathogen in the EU. Poultry are a common source of infection to humans, and turkey flocks are commonly colonized with the organism. We investigated the prevalence and risk factors of Salmonella infection in 179 houses in 60 holdings representative of turkey meat and breeder production in Great Britain. From each holding, up to four houses were chosen, and two consecutive flocks per house were sampled/tested for Salmonella to investigate the persistence, elimination and introduction of Salmonella in consecutive crops. At the first sampling, the overall flock‐level Salmonella prevalence was 32.8% and 8.9% for meat and breeding flocks respectively. There was a higher prevalence of Salmonella in flocks in the rearing stage than in the fattening and breeding stages. At the first sampling, the flock‐level prevalence of Salmonella was 26.8% (95% CI: 20.7–33.7%), while the prevalence level in the subsequent flock was 20.5% (95% CI: 13.6–29.7%). No houses were positive for any of the EU‐regulated serovars. The most commonly encountered serovars were S. Kottbus and S. Kedougou. Carry‐over of infection was observed in 44.8% of the positive houses, and introduction of new infection occurred in 8.4% of houses. Data from the questionnaires and auditing of all holdings and houses were combined and used to calculate adjusted farm‐ and house‐adjusted risk factors. Significant risk factors were feed from a source other than a national compounder (OR = 2.4), feeder type other than pan feeders (OR = 2.4) and hygiene practices other than terminal cleaning and disinfection using power‐washing with sanitizer and anteroom with boot change (OR = 2.8). The study discusses the main challenges currently faced by the industry to control Salmonella in turkey production. 相似文献
74.
《Communications in Soil Science and Plant Analysis》2012,43(13):1784-1798
Turkey has almost 70% of the total boron (B) in the world, and B-reserve areas form a special habitat in terms of plant–environment relationships. In this study, these relationships were used to investigate phytoremediation possibilities for B-contaminated environments. Field studies were carried out in seven different open B mine sites and their environments in four different provinces of Turkey. At the end of chemical analyses of soil and plant samples, 11 wild and potential phytoremediator plant species were determined; two of them were aquatic whereas nine were terrestrial. Some of the species were halophytes. Puccinella distans subsp. distans (Poaceae) and Gypsophila perfoliata subsp. perfoliata (Caryophyllaceae) showed both the greatest tolerance and greatest B accumulation ratios. The results of the present study could be used as a tool to improve effective and environmentally friendly management strategies for both aquatic and terrestrial environments contaminated with high B concentrations. 相似文献
75.
Twenty chicks, 12 turkey poults and 10 ducklings, all 5 weeks old were infected with 2 × 103.5 chick LD50 IBD virus to determine the course of the virus in the 3 poultry species. Uninfected control birds were kept separately. Two
infected and 2 control birds/species were euthanized at time intervals between 3 and 168 hours post infection (pi). Sections
of thymus, bursa of Fabricius, spleen, liver, kidney, proventriculus and ceacal tonsil were stained for the detection of IBD
virus antigen using immunoperoxidase technique. IBD virus antigen positive cells stained reddish-brown and the amount of such
cells in tissue sections were noted and scored. Stained cells were present in all organs examined for up to 168 hours pi in
the 3 poultry species except ceacal tonsils of ducks at 72 and 120 hours pi. Antigen score was highest in chickens and least
in ducks as reflected by average of total scores/sampling time of 12, 10.8 and 8 in chickens, turkeys and ducks respectively.
Total antigen score/sampling time in infected chickens peaked twice; 24/48 and 144 hours pi, whereas such bi-phasic peaks
were absent in turkeys and ducks. Range of total antigen score at different sampling times was 7–17.5 in chickens, 10–13 in
turkeys and 7–10 in ducks indicative of marked viral replication in chickens. Presence of IBD viral antigen in organs of all
3 poultry species is indicative of infections. The innate ability of turkeys and ducks to prevent appreciable replication
of IBD virus after infection requires further investigation. 相似文献
76.
Takuya Buto Kazuki Suzuki Tomoyuki Kaidzu Taishi Narisawa Oguz Can Turgay Ibrahim Ortas 《Arid Land Research and Management》2016,30(4):479-489
A minimal amount of information is currently available concerning arbuscular mycorrhizal (AM) fungal associations with crops in semi-arid zones on Leptosols in Turkey. Therefore, using molecular ecological techniques, we studied the effects of different management practices (without fertilization, chemical fertilization, farmyard manure, and plant compost amendments) on AM fungal communities associated with wheat roots. Experiments were conducted in a field established in 1996 in southern Mediterranean Turkey where soil productivity is low owing to unfavorable climatic effects and soil characteristics. We determined 201 partial sequences of AM fungal nuclear ribosomal large subunit genes. The higher AM fungal richness was found in the control treatment without fertilization and plant compost treatments compared with the chemical fertilization and farmyard manure treatments. Clones related to Rhizophagus were found in all treatments and accounted for 37% of the total AM fungal clones, whereas those of Funneliformis were dominant under chemical fertilization. Redundancy analysis based on the frequency of operational taxonomic units revealed that AM fungal communities were divided into three groups, namely, the control treatment, the chemical fertilization treatment, and the organic treatments (farmyard manure and plant compost treatments). Although different organic amendments supported relatively similar AM fungal communities, plant compost induced higher AM fungal richness than farmyard manure fertilization. 相似文献
77.
78.
The study deals with the tachinid parasitoids ofAncyrosoma leucogrammes (Gmelin) (Heteroptera: Pentatomidae):Clytiomya dupuisi Kugler,Clytiomya sola (Rondani) andGymnosoma clavatum (Rohdendorf) (Diptera: Tachinidae). All species are recorded for the first time as parasitoids ofA. leucogrammes, andC. dupuisi was reared for the first time from a host. The parasitization rates ofC. dupuisi on adults ofA. leucogrammes varied from 7% to 9% between 1994 and 1999.C. sola andG. clavatum were reared in only small numbers.
http://www.phytoparasitica.org posting July 10, 2003. 相似文献
79.
Studies were carried out on the egg material ofTraumatocampa ispartaensis Doganlar & Avcı (Lep.: Notodontidae) collected onCedrus libani A. Rich. A total of 95 egg-batches were sampled over two annual generations ofTr. ispartaensis. The number of eggs in each egg-batch varied between 39 and 245 and the length of the batches varied between 7 and 36 mm.
The mean number of eggs per batch was found to be 119 and 122 in 1999 and 2000, respectively. Based on field data the oviposition
period continued from mid August to mid September. The mean hatching rate of the host was found to be 85.8% and 88.9%, whereas
the impact of egg parasitoids accounted for 11.3% and 7.4%, respectively in the 2 years.Ooencyrtus pityocampae (Mercet) was observed as the most abundant egg parasitoid, followed byOoencyrtus sp. nearmasii (Mercet) andTrichogramma brassicae Bezdenko. Based on the emergence dynamics of the egg parasitoids in the laboratory, it seems thatO. pityocampae emerged mainly in June whereasO. sp. nearmasii andT. brassicae emerged mainly in May.
http://www.phytoparasitica.org posting Feb. 3, 2003. 相似文献
80.
Performance indicators for locally managedirrigation systems in the Gediz Basin,Turkey, show that during the first fouryears after management transfer there wasbeen a continued improvement in irrigationperformance. While the area cropped usingsurface water has only marginally improved,yields and water productivity have shownsignificant increases. These benefits canbe attributed in part to favorable marketconditions for cotton and grapes, but alsoto a management system that values level ofservice so that farmers are not constrainedby uncertainties in water deliveries. Individual systems are managed quitedifferently within the Gediz Basin showingthat there is scope for considerablediversity in Irrigation Associationspractices without affecting the resultingperformance of systems. 相似文献