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101.
A survey of stored product pests, their natural enemies, grain storage and pest management approaches in northern Namibia
was conducted. The survey revealed five types of crop commodities (pearl millet, sorghum, cowpea, maize, feed mixture) stored
in four types of grain stores (baskets, bag stags-flat stores, concrete bin, metal containers). No synthetic pesticides or
plastic sheeting was recorded. Wooden-ash natural pesticide is the only protectant used. Ten insect pest species were found
affiliated to the orders of Coleoptera (Attagenus fasciatus, Callosobruchus subinnotatus, Cryptolestes ferrugineus, Oryzaephilus surinamensis, Rhyzopertha dominica and Tribolium castaneum), Lepidoptera (Corcyra cephalonica, Sitotroga cerealella), Psocoptera (Liposcelis paeta) and Blattodea (Blattella germanica). Out of these, seven species were recognized as new stored-products pests for Namibia. Although listed for southern Africa
region, no storage pest-mites (Acari) and Sitophilus spp., Prostephanus sp. or Trogoderma sp. beetles were traced. We found four new species of natural enemies of storage pests recruiting from insects (Habrobracon hebetor, Cephalonomia wattersoni, Brachymeria sp.) and mites (Blattisocius tarsalis). The occurrence of natural enemies indicates a potential for pest bio-control in Namibian grain stores. 相似文献
102.
Erhard Halmschlager Christof Ladner Petr Zabransky Axel Schopf 《Journal of pest science》2007,80(1):59-61
The wood boring weevil, Pentarthrum huttoni Wollaston, is reported for the first time from Austria. It was recorded from coffins in the crypt of St. Michael’s church
in the centre of Vienna. Extensive tunnelling of the larvae and surface damage by the adults caused disintegration of the
historically significant wooden 18th century coffins. Beetles were also detected in rotten cardboard on the loamy soil of the crypt. Infestation by this Cossonine
weevil is promoted by the very damp conditions in the crypt, a consequence of the closure of ventilation funnels in the 1940s. 相似文献
103.
Only little is known about normal oral bacterial flora in captive snakes containing Stenotrophomonas maltophilia. This microbe has been reported as a causative agent of numerous infections in reptiles. Therefore, the goal of the study was to detect its presence in the mouths of a significant number of healthy captive snakes and determining its susceptibility to antibiotics at 30 and 37 degrees C. The isolates were obtained in 1999-2005 from mouth swabs of 115 snakes of 12 genera and 22 species-most often Elaphe guttata (24 individuals; 20.9%). Susceptibility to 24 antibiotics was tested by the microdilution method. The microbe was demonstrated in 34 (29.6%) individuals. Overall, 47 strains of S. maltophilia were acquired. Evaluation using PFGE profiles and antibiograms resulted in confirmation of one strain of S. maltophilia in 23 (20.0%) individuals, two strains in nine (7.8%) and three in two (1.8%) snakes. All tested antibiotics were more effective at 37 degrees C, with the partial exception of cotrimoxazole and cefoperazone/sulbactam. At a temperature of 37 degrees C, the lowest frequency of resistance to levofloxacin (no resistant strains), cotrimoxazole and ofloxacin (97.9% of susceptible strains) was recorded. At 30 degrees C, the most active agents were cotrimoxazole (97.9% of susceptible strains), levofloxacin (91.5%) and ofloxacin (85.1%). In conclusion, S. maltophilia is present in the mouths of about one third of healthy captive snakes, showing good susceptibility to cotrimoxazole, some fluoroquinolones and aminoglycosides. The antibiotics (particularly aminoglycosides) are more effective at 37 degrees C. 相似文献
104.
Chloupek P Vecerek V Voslarova E Bedanova I Suchy P Pistekova V Kozak A 《Berliner und Münchener tier?rztliche Wochenschrift》2008,121(3-4):132-136
Effects of different crating periods on selected biochemical indices were monitored in a group of unsexed ROSS 308 broiler chickens aged 42 days. 120 randomly selected chickens were weighted and placed in 15 heavy duty plastic crates with reduction in floor space approx. 160 cm2/kg of body weight of broilers (average body weight was 2.75 kg). Five crates were kept for 4 hours (Group 4h), another five crates for 8 hours (Group 8 h) and another five crates for 12 hours (Group 12h). After tested periods of crating the broilers were released and blood samples were withdrawn from Vena bosilico in 24 randomly selected birds from each group (Groups 4 h, 8 h, 12 h respectively) and also in other 24 randomly selected non-crated control birds. The results of our experiment proved that duration of crating significantly influenced the stress response in broiler chickens. The duration of crating period was positively correlated with the plasma corticosterone level and negatively correlated with the lactate dehydrogenase, cholesterol, triglycerides, glucose and lactate levels in the blood of broiler chickens. 相似文献
105.
V Rada K Sirotek J Petr 《Zentralblatt für Veterin?rmedizin. Reihe B. Journal of veterinary medicine. Series B》1999,46(6):369-373
Five media were evaluated to determine their selectivity for Bifidobacterium sp. in hen and rabbit caecal samples. The colonies arising on the plates inoculated with the caecal samples were Gram stained and screened for the presence of fructose-6-phosphate phosphoketolase activity. Rogosa agar modified by the addition of cysteine-hydrochloride (0.05% w/v), Beeren's agar (with 5 ml/l of propionic acid as a selective agent), BS 2 agar (containing per one litre sodium propionate 15 g, lithium chloride 3 g, paromomycin sulphate 50 mg, neomycin sulphate 200 mg), and Wilkins-Chalgren agar (MW) modified by the addition of acetic acid (1 ml/l) and mupirocin (100 mg/l) were selective for Bifidobacterium sp. from rabbit caecal samples. In contrast, only MW medium was suitable for the isolation and enumeration of bifidobacteria in hen caecal samples. In conclusion, the results suggest that MW agar showed the greatest selectivity. A further advantage of this medium is its case of preparation. Therefore this agar could contribute to the study of the effects of the ingestion both probiotics and prebiotics. Finally, it could be noted that the bifidobacteria selective media should be chosen in respect of the animal species origin of the sample tested. 相似文献
106.
Five media were evaluated to determine their selectivity for Bifidobacterium sp. in hen and rabbit caecal samples. The colonies arising on the plates inoculated with the caecal samples were Gram stained and screened for the presence of fructose-6-phosphate phosphoketolase activity. Rogosa agar modified by the addition of cysteine-hydrochloride (0.05 % w/v), Beeren’s agar (with 5 ml/l of propionic acid as a selective agent), BS 2 agar (containing per one litre sodium propionate 15 g, lithium chloride 3 g, paromomycin sulphate 50 mg, neomycin sulphate 200 mg), and Wilkins-Chalgren agar (MW) modified by the addition of acetic acid (1 ml/l) and mupirocin (100 mg/l) were selective for Bifidobacterium sp. from rabbit caecal samples. In contrast, only MW medium was suitable for the isolation and enumeration of bifidobacteria in hen caecal samples. In conclusion, the results suggest that MW agar showed the greatest selectivity. A further advantage of this medium is its ease of preparation. Therefore this agar could contribute to the study of the effects of the ingestion both probiotics and prebiotics. Finally, it could be noted that the bifidobacteria selective media should be chosen in respect of the animal species origin of the sample tested. 相似文献
107.
The feeding success of sand flies (Diptera: Phlebotominae) is linked to the vast array of pharmacological substances in their saliva, which interferes with the host haemostasis and immune response. Modification of feeding site plays also an important role in Leishmania transmission. In naive hosts, co-inoculation of saliva and Leishmania parasites increases the chance of successful transmission. Disease exacerbation seems to be associated with enhanced production of type 2 cytokines and selective inhibition of some macrophage functions including the production of NO and H202. On the other hand, hosts repeatedly exposed to sand fly bites develop anti-saliva immune response that results in a protection against Leishmania infection. This led to a new interesting approach to anti-Leishmania vaccine--using salivary components to block parasite transmission. The review is therefore focused on the interactions that run between immunomodulatory molecules in sand fly saliva and host immune response, with the impact on Leishmania infection development. Recent studies revealed that saliva-based vaccine for leishmaniasis might be effective and feasible, however, several questions still require to be solved. The knowledge based on experimental mouse model cannot be fully extrapolated to dogs or humans and due to differences in salivary antigens between sand fly species the protective effect is species-specific. On the other hand, the specificity of salivary antigens enables the use of anti-saliva antibodies for monitoring the exposure of hosts to sand fly bites and might be used as a marker of risks for Leishmania transmission in endemic areas. 相似文献
108.
P Jakubec M Bancirova V Halouzka A Lojek M Ciz P Denev N Cibicek J Vacek J Vostalova J Ulrichova J Hrbac 《Journal of agricultural and food chemistry》2012,60(32):7836-7843
This work describes the method for total antioxidant capacity (TAC) and/or total content of phenolics (TCP) analysis in wines using microdialysis online-coupled with amperometric detection using a carbon microfiber working electrode. The system was tested on 10 selected wine samples, and the results were compared with total reactive antioxidant potential (TRAP), oxygen radical absorbance capacity (ORAC), and chemiluminescent determination of total antioxidant capacity (CL-TAC) methods using Trolox and catechin as standards. Microdialysis online-coupled with amperometric detection gives similar results to the widely used cyclic voltammetry methodology and closely correlates with ORAC and TRAP. The problem of electrode fouling is overcome by the introduction of an electrochemical cleaning step (1-2 min at the potential of 0 V vs Ag/AgCl). Such a procedure is sufficient to fully regenerate the electrode response for both red and white wine samples as well as catechin/Trolox standards. The appropriate size of microdialysis probes enables easy automation of the electrochemical TAC/TCP measurement using 96-well microtitration plates. 相似文献
109.
Valentova K Stejskal D Bednar P Vostalova J Cíhalík C Vecerova R Koukalova D Kolar M Reichenbach R Sknouril L Ulrichova J Simanek V 《Journal of agricultural and food chemistry》2007,55(8):3217-3224
This study assessed the effect of an 8 week consumption of dried cranberry juice (DCJ) on 65 healthy young women. Basic biochemical and hematological parameters, antioxidant status, presence of metabolites in urine, and urine ex vivo antiadherence activity were determined throughout the trial. A 400 mg amount of DCJ/day had no influence on any parameter tested. A 1200 mg amount of DCJ/day resulted in a statistically significant decrease in serum levels of advanced oxidation protein products. This specific protective effect against oxidative damage of proteins is described here for the first time. Urine samples had an inhibitory effect on the adhesion of uropathogenic Escherichia coli strains, but no increase in urine acidity was noted. Hippuric acid, isomers of salicyluric and dihydroxybenzoic acids, and quercetin glucuronide were identified as the main metabolites. In conclusion, cranberry fruits are effective not only in the prevention of urinary tract infection but also for the prevention of oxidative stress. 相似文献
110.