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71.
Kavallieratos NG Athanassiou CG Pashalidou FG Andris NS Tomanović Z 《Pest management science》2005,61(7):660-666
Laboratory bioassays were carried out in order to evaluate the effectiveness of two diatomaceous earth (DE) formulations, Insecto and SilicoSec, against adults of Rhyzopertha dominica (F) in eight different grain commodities. The adherence of the two DEs to each grain was also measured. The eight grains tested were wheat, whole barley, peeled barley, oats, rye, triticale, rice and maize. These commodities were treated with the DEs at three rates, 0.75, 1.0 and 1.5 g DE kg(-1) grain. The mortality of R dominica adults was measured after 24 h, 48 h, 7 days and 14 days of exposure in the treated grains at 26 degrees C and 55% RH. After the 14-day mortality count, all adults were removed and the treated grains retained under the same conditions for a further 60 days. The treated grains were subsequently examined for F1 progeny. Significant differences were recorded among the eight grain types as well as between the DE formulations tested. After 14 days of exposure, even at the lowest DE rate for both formulations, adult mortality was high (>90%) in wheat and triticale. In contrast, adult mortality was significantly lower in peeled barley. Increasing the rate improved the efficacy of the DEs significantly in only some of the grains tested. Reproductive capacity in all the treated grains was significantly suppressed when compared with untreated grains. Generally, more F1 individuals of R dominica were noted in the treated peeled barley than in the other commodities. Significant differences in the percentage of DE retention were noted among the eight grains. The highest retention level was noted in rice (>87%) and the lowest in maize (<6%). However, the degree of DE adherence to a given grain was not always indicative of the effectiveness of DE against R dominica. 相似文献
72.
Metabolic diseases of cows represent the leading internal pathology in Lithuania in terms of incidence and economic impact. This paper summarizes the mineral metabolic state of milk cows, and details the influence of feeding on serum levels of calcium, nonorganic phosphorus, magnesium, potassium, sodium, glucose, total protein, and urea quantity, and correlationd among them, in healthy dry or post-calving cows as well as in cows with osteomalacia and milk fever after calving. There was less pronounced hypocalcaemia and there were only minor changes in phosphorus, magnesium, potassium and sodium in the serum of healthy dry and post-calving cows that had silage and mineral-vitamin supplements, compared to cows that did not have supplements and silage. There was a fall in calcium and phosphorus (to 1.89 +/- 0.12 mmol/L and 0.71 +/- 0.06 mmol/L, respectively) in the blood of cows sick with milk fever after calving, while levels of magnesium and potassium were increased. The correlation between calcium and phosphorus was r = 0.6993, p < 0.001 in the serum of sick cows. There was a fall in calcium, phosphorus and magnesium (to 1.86 +/- 0.46 mmol/L, 0.75 +/- 0.37 mmol/L, and 0.60 +/- 0.19 mmol/L, respectively) and an increase in sodium level (to 158.90 +/- 19.30 mmol/L) in the blood of cows with osteomalacia in comparison with healthy cows. 相似文献
73.
The presence of American liver fluke (Fascioloides magna) in Croatian wild ruminant species was detected for the first time in January 2000. At the same time, the problem of adequate parasitological monitoring and treatment appeared in the captive deer population. Quarantine and health screening protocols, as well as migration and transportation influence had to be evaluated in red deer husbandry. Non-invasive methods were introduced to estimate the prevalence of F. magna in the semi-farm rearing system. Coprological analysis has been performed on 264 faecal samples. The most effective antiparasitic treatment was implemented on herd and individual treatment. Treatment was extended to the free-ranging population of deer in the same region. 相似文献
74.
E. Stânková-Opočenská J. Dekker 《European journal of plant pathology / European Foundation for Plant Pathology》1970,76(3):152-158
Protection of cucumber seedlings against damping off, caused byPythium debaryanum, was obtained by soaking the seeds in a solution of 1 ppm 6-azauracil (AzU), but not by treatment with a 10 or 100 ppm AzU solution. After the 1 ppm AzU treatment of the seeds, the rhizosphere microflora of the developing seedlings was changed; an increase of the bacterial population and a decrease of the fungal population was observed. SinceP. debaryanum is rather insensitive to AzU in vitro, it is suggested that the control of damping off is obtained in an indirect way, possibly via the microflora of the roots.Samenvatting Bescherming van komkommerzaailingen tegen aantasting doorPythium debaryanum werd verkregen na weken der zaden in een oplossing van 1 ppm 6-azauracil (AzU); 10 en 100 ppm AzU waren niet werkzaam. Na behandeling der zaden met 1 ppm AzU traden veranderingen in de rhizosfeermicroflora der kiemplanten op; de bacteriepopulatie nam toe en de schimmelpopulatie nam af. AangezienP. debaryanum in vitro vrijwel ongevoelig is voor AzU, wordt verondersteld dat de bescherming tegen aantasting door deze schimmel op indirecte wijze verkregen wordt, mogelijk via de microflora van de wortels. 相似文献
75.
Naturally occurring antimutagenic factors, especially those of plant origin, have recently become a subject of intensive research. Antimutagenic properties of terpenoid fractions of sage (Salvia officinalis) were tested in mammalian system in vivo through examining the ability of sage to decrease the frequency of aberrant cells induced by a potent mutagen. First, groups of mice were treated with three concentrations of sage alone and it was established that the frequency of aberrant cells after treatment with a concentration of 25 microL/kg was not significantly different from the negative control (olive oil), while that found after treatment with the 50 microL/kg concentration differed significantly (chi2(1) = 4.05, p < 0.05). Sage used at a concentration of 100 microL/kg was cytotoxic. Mitomycin C (MMC), known as a potent mutagen, was used for induction of chromosome aberrations. Post-treatment with sage suppressed the effects of MMC significantly. Both concentrations (25 microL/kg and 50 microL/kg) produced a significant decrease in the frequency of aberrations relative to MMC (chi2(1) = 5.42, p < 0.02, chi2(1) = 14.93, p < 0.001, respectively). The percent of aberrations decreased with increasing concentrations of sage. Only nontoxic concentrations of sage without mutagenic effects can be recommended for use as inhibitors of mutagenesis or carcinogenesis. 相似文献
76.
Antimicrobial resistance of Salmonella isolated from finishing swine and the environment of 60 Alberta swine farms 总被引:5,自引:0,他引:5
Rajić A McFall ME Deckert AE Reid-Smith R Manninen K Poppe C Dewey CE McEwen SA 《Veterinary microbiology》2004,104(3-4):189-196
The study objective was to describe and evaluate antimicrobial resistance profiles in Salmonella isolated from Alberta swine finishing farms. Salmonella isolates (n = 322) were obtained from 192 fecal and 84 environmental samples of the 60 Salmonella-positive swine finishing farms. Isolates were classified susceptible, intermediate or resistant based on NCCLS guidelines. More than half of the isolates (53.4%) were susceptible to all of the 18 antimicrobials in the testing panel. No resistance was observed to amikacin, amoxicillin/clavulanic acid, cefoxitin, ceftiofur, ceftriaxone, cephalothin, ciprofloxacin, imipenem or nalidixic acid. Less than 1% of isolates were resistant to apramycin, gentamicin and trimethoprim/sulfamethoxazole. Higher frequencies of resistance were observed for chloramphenicol (4.7%), ampicillin (7.8%), kanamycin (11.8%), sulfamethoxazole (21.1%), streptomycin (25.5%) and tetracycline (38.8%). Eleven Salmonella serovars had isolates with resistance to > or =3 antimicrobials. The most frequently resistant serovar was Salmonella Derby, with 27 (38.0%) isolates resistant to > or =3 antimicrobials, including resistance to five and six antimicrobials. An absence of resistance to cephalosporins and fluoroquniolones and a low proportion of isolates resistant to amikacin, amoxicillin/clavulanic acid, apramycin, gentamicin and trimethoprim/sulfamethoxazole are encouraging findings from public health and animal health perspectives. Frequent resistance observed for ampicillin, kanamycin, sulfamethoxazole, streptomycin and tetracycline, antimicrobials commonly used in veterinary medicine for decades, indicates an urgent need to utilize these antimicrobials more prudently if their benefits are to be preserved. 相似文献
77.
Sobocanec S Sverko V Balog T Sarić A Rusak G Likić S Kusić B Katalinić V Radić S Marotti T 《Journal of agricultural and food chemistry》2006,54(21):8018-8026
Native propolis was defined as propolis powder collected from the continental part of Croatia and prepared according to a patented process that preserves all the propolis natural nutritional and organoleptic qualities. Nine phenolic compounds (out of thirteen tested) in propolis sample were detected by high performance liquid chromatography (HPLC) analysis. Among them chrysin was the most abundant (2478.5 microg/g propolis). Contrary to moderate antioxidant activity of propolis examined in vitro (ferric reduction antioxidant power; FRAP-assay), propolis as a food supplement modulated antioxidant enzymes (AOE) and significantly decreased lipid peroxidation processes (LPO) in plasma, liver, lungs, and brain of mice. The effect was dose- and tissue-dependent. The lower dose (100 mg/kg bw) protected plasma from oxidation, whereas the higher dose (300 mg/kg bw) was pro-oxidative. Hyperoxia (long-term normobaric 100% oxygen) increased LPO in all three organs tested. The highest vulnerability to oxidative stress was observed in lungs where hyperoxia was not associated with augmentation of AOE. Propolis protected lungs from hyperoxia by increased catalase (CAT) activity. This is of special importance for lungs since lungs of adult animals are highly vulnerable to oxidative stress because of their inability to augment AOE activity. Because of its strong antioxidant and scavenging abilities, native propolis might be used as a strong plant-based antioxidant effective not only in physiological conditions but also in cases that require prolonged high concentration of oxygen. 相似文献
78.
Twelve American Staffordshire terriers, gestational day 60, and 10 dogs de Bordeaux, gestational day 57 were examined in respect of the morphology and morphometry of their intraorbital muscles. The location of the retractor bulbi, recti and oblique muscles was described and the length of the muscles, the length and breadth of their tendons as well as the distance of the distal insertions of the muscle tendons from the corneal limbus were measured. Similarly, the shape of the line of distal insertions was investigated. The measurements were taken with an electronic caliper to the nearest 0.1 mm. The distance insertion-corneal limbus was measured by means of the Hifny and Misk method (1982). The following differences between the breeds in the morphometry of the intraorbital muscles and their tendons were found out. The distal insertions of the tendons of the dorsal, ventral and lateral recti muscles are further from the corneal limbus in American Staffordshire terriers than in dogs de Bordeaux. The muscular funiculi of the retractor bulbi muscle are further from the corneal limbus in dogs de Bordeaux, except the dorsolateral funiculus (1.96/1.94 mm). In addition, there are differences in the morphometry of the intraorbital muscles and their tendons. No differences, however, were found in the morphology of the intraorbital muscle tendons (their insertion line) and their location. The study can be applied to clinical sciences (surgery) and veterinary ophthalmology, in particular. 相似文献
79.
Svetlana Milija?evi?-Mar?i? Biljana Todorovi? Ivana Poto?nik Milo? Stepanovi? Emil Rekanovi? 《Phytoparasitica》2012,40(3):299-303
Symptoms of brown blotch were observed on cultivated Agaricus bisporus on several mushroom farms in Serbia. Subsequently, samples were collected from nine localities during 2006?C2010 and fluorescent Gram-negative bacterial strains were isolated. All strains caused sunken brown lesions on A. bisporus tissue blocks after artificial inoculation. Isolated strains showed the LOPAT characteristics of the group Va being negative for levan production; the ability to produce a hypersensitivity reaction in tobacco; were oxidase and arginine dihydrolase positive; and lacked pectolytic activity. The results from other tests were as follows: oxidative metabolism of glucose; catalase activity positive; aesculin hydrolisis negative; Tween 80 hydrolysis positive; casein hydrolysis positive; gelatine hydrolysis and nitrate reduction negative; mannitol, erythritol, sorbitol, inositol and trehalose were used as a carbon source but not sucrose, arabinose and D(-) tartrate. Based on these features bacterial strains were identified as Pseudomonas tolaasii. The identity of isolated strains was confirmed by polymerase chain reaction. This is the first report of P. tolaasii in Serbia. 相似文献
80.
Fan S Baets R Petrov A Yu Z Joannopoulos JD Freude W Melloni A Popović M Vanwolleghem M Jalas D Eich M Krause M Renner H Brinkmeyer E Doerr CR 《Science (New York, N.Y.)》2012,335(6064):38; author reply 38
We show that the structure demonstrated by Feng et al. (Reports, 5 August 2011, p. 729) cannot enable optical isolation because it possesses a symmetric scattering matrix. Moreover, one cannot construct an optical isolator by incorporating this structure into any system as long as the system is linear and time-independent and is described by materials with a scalar dielectric function. 相似文献