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931.
932.
Berit Muan Janneche Utne Skre Nils E. Sli Kari Grave Stig
degaard 《Acta veterinaria Scandinavica》1985,26(3):352-362
The clinical effect, residues in milk and toxicological properties of a non-commercial formulation of malathion used as an ectoparasitic agent on cattle were investigated. The results show that the malathion preparation has a desired clinical effect. The maximum concentration of malathion in milk after topical application of 5 g malathion was 0.054 μg/ml 4–6 h post-treatment, and declined to 0.005 and 0.002 μg/ml 24 and 48 h post-treatment, respectively. Totally 0.006–0.03 % of the applied dose was excreted in the milk. No toxic effect, measured as inhibition of the cholinesterases in erythrocytes and plasma, could be detected after therapeutic use of malathion.The pharmacokinetic evaluation after 2.5 g intravenous administration of malathion, indicated that the kinetics could probably be described by a multicompartment model. 相似文献
933.
K. Ramamoorthy M. Kannathasan D. Kalavathi 《Journal of Agronomy and Crop Science》1991,166(5):353-358
Soil application of different formulations of carbofuran at 3.0 and 1.5 g.a.i. metre row−1 did not have any impact on vigour and viability of the resultant seeds of sorghum. Fresh seeds from encecap 'A', encecap 'B' and furadan treated plots contained higher residues than the permissible limits and in artificially aged seeds the quantities were below the permissible limits. The degradation was evident with the growth and development of seedlings grown from fresh and aged seeds. Residues from lower doses dissipated faster than higher doses. The general decline in percentage germination and vigour could not be attributed to the residual toxicity but only to the ageing phenomena. 相似文献
934.
The persistence of the acaricide tau-fluvalinate with time and the factors that can affect its degradation in honey were investigated. Two honey types of extreme pH values (3.85 and 5.40) were spiked with tau-fluvalinate at two levels (50 and 200 micrograms kg-1) and incubated at 35 degrees C. Samples were analyzed in duplicate at various time intervals for up to 248 days. A simple, rapid and accurate method for the determination of tau-fluvalinate residues in honey is proposed. Tau-fluvalinate extraction and sample cleanup was carried out using C8 SPE cartridges with dichloromethane as the elution solvent. Analysis of samples was accomplished using gas chromatography with electron-capture detection (GC-ECD). The overall recovery of the method was 90.25 (+/- 0.85)% and the limit of determination 1 microgram kg-1. The results showed that tau-fluvalinate stays stable in honey for more than 8 months, even at 35 degrees C. The effect of higher temperatures, similar to those used for honey packing, on tau-fluvalinate persistence in honey was also studied. Honey samples fortified with 20 and 200 micrograms kg-1 tau-fluvalinate were subjected to heat treatment similar to that in the honey blending and packing process. No degradation of tau-fluvalinate due to the heat treatment was recorded. This long persistence increases the risk of honey contamination due to repeated and/or extended tau-fluvalinate applications. 相似文献
935.
Nine key forage species (grasses and legumes), together with two types of crop residues, usually fed by farmers to their livestock, were collected from a rainfed area in western Sudan during the dry season (May–April). The grasses investigated were Leptadena pyrotechnia, Cenchrus setigrus, Arista pallida, Eragrotis tremula, Schoenefeldia gracilis, Chloris vergata and Cenchrus biflorus. The crop residues investigated were the grasses, sorghum straw (Sorghum bichlor) and millet straw (Pennisetum typhodium) and the legumes Stylosanthes flavicans and Cajanus cajana. Estimates of organic matter (OM) degradability were done using the nylon bag technique, which was fitted into the model Y = a + b (1 – e–ct), in which the asymptote (a + b) represented the total potential degradability. Organic cell wall constituents and hence both metabolizable energy and total digestible energy or nutrients (TDN) were determined. S. flavicans showed the best organic matter degradability, and sorghum straw was better degraded than millet straw. The rest of the grasses showed poor OM degradability. Acid detergent insoluble nitrogen was inversely related to TDN, the latter falling within a narrow range for the different forages. Fermentable metabolizable energy differed only slightly, while the legume S. flavicans had the highest effective rumen digestible protein. Undegraded proteins were high for the straws and the grasses L. pyrotechnia and C. setigerus. Metabolizable protein and microbial protein were highest in the sorghum straw, C. setigerus and S. flavicans. 相似文献
936.
Laboratory studies on the formation of bound residues and on the degradation of the triazole fungicide propiconazole were conducted in two different soils. Soils treated with 14C-propiconazole were incubated at 22 degrees C and extracted exhaustively with a solvent at each sampling date until no further propiconazole was extracted. The solvent-extractable residues were used to measure propiconazole remaining in the soil, and the extracted soils were used to investigate bound residues of propiconazole. Mineralization of propiconazole was investigated by measuring [14C]carbon dioxide evolved from the soil samples. Formation of bound residues of propiconazole was higher in silty clay loam soil than in sandy loam soil, giving approximately 38 and 23% of the applied 14C, respectively. In contrast, the rates of degradation and mineralization of propiconazole were lower in silty clay loam soil than in sandy loam soil. Decreased extractability of the 14C residues with incubation time was observed with increased formation of bound residues. When the propiconazole remaining in the solvent-extractable residues was quantitatively measured by high-pressure liquid chromatographic analysis, the half-life value in sandy loam soil was about 315 days, while the half-life in silty clay loam soil exceeded the duration of the 1 year experimental period. Increased formation of bound residues was observed as propiconazole degraded with incubation time, suggesting that degradation products are involved in the formation of bound residues. Our study suggests that the formation of bound residues of propiconazole contributes to the persistence of this fungicide in soil. 相似文献
937.
Rule R Moreno L Serrano JM Roman AG Moyano R Garcia J 《Australian veterinary journal》2001,79(7):492-496
OBJECTIVE: To determine for two commercial preparations of oxytetracycline (OTC) the pharmacokinetic behaviour, the presence of detectable milk residues and the penetration in milk of OTC administered by intravenous (IV) (conventional formulation [CF]) and intramuscular (IM) routes (CF and long-acting [LA] formulations) in goats producing milk. The effects of these formulations on plasma activity values of creatine kinase (CK) and lactate dehydrogenase (LDH) were also determined as indicators of tissue damage. PROCEDURE: Five healthy lactating goats producing 1.5+/-0.5 L/d milk and weighing 56.0+/-4.8 kg were used. Single doses of OTC chlorhydrate (CF) were administered (20 mg OTC/kg) by IV (Trial 1 IV) and IM (Trial 1 IM) routes and OTC dehydrate (LA) by the IM route. The same goats were first given IV CF, then IM CF followed by IM LA with 3 weeks between each treatment. Blood and milk samples were taken. The quantification of OTC was performed by HPLC and the plasma activities of CK and LDH enzymes were determined by spectrophotometry. The presence of OTC residues in milk was determined by a commercial reagent. The plasma pharmacokinetic parameters were calculated using a two-compartment model. RESULTS: Estimates of kinetic variables following IV administration were: Vss= 400.0+/-120.0 mL/kg and CL= 110.0+/-14.0 (mL/h)/kg. The t(fi) for IV= 3.0+/-0.3 h; IM, CF = 10.5+/-2.1 h and IM, LA = 15.1+/-3.1 h. The concentration of OTC in milk at 48 h was: IV= 0.6+/-0.4; IM CF= 1.1+/-0.2 and at 72 h (IM LA)= 0.6+/-0.1 microg/mL and the penetration in milk of OTC was: IV= 70.0+/-18.0; IM CF= 79.0+/-14.0 and IM LA= 66.0+/-6.0%. The areas under the curve of CK and LDH activities in plasma were calculated by the trapezoidal method. Values of CK and LDH IM, LA were greater (P < 0.05) than those observed for IM, CF at 2 and 3 days after administration of the antibiotic. Finally, the bioavailability of OTC CF = 92.0+/-22.0 and LA= 78.0+/-23.0% was suitable for its usage by the IM route in lactating goats. CONCLUSION: Plasma concentration-time values of OTC administered parenterally in production dairy goats showed similar bioavailability for the two pharmaceutical preaprations. The presence of detectable residues in milk indicates that milk should not be used for human consumption for 2 and 3 days after administration of conventional and long-acting formulations, respectively. The increments in CK and LDH activities after the IM administration of LA are consistent with the presence of tissue damage provoked by the pharmaceutical preparations at the injection site. 相似文献
938.
安徽省茶叶农药残留现状与控制措施 总被引:8,自引:0,他引:8
本文结合本省茶树的主要病虫发生和防治情况,对茶叶农药残留现状和欧盟新农残标准对我省茶叶出口的影响进行了论述,总结并提出了安徽省茶叶农药残留的控制措施。 相似文献
939.
The effect of microclimate variables on development ofClonostachys rosea and biocontrol ofBotrytis cinerea was investigated on rose leaves and crop residues. C.rosea established and sporulated abundantly on inoculated leaflets incubated for 7–35 days at 10°, 20° and 30°C and then placed
on paraquat—chloramphenical agar (PCA) for 15 days at 20°C. On leaflets kept at 10°C, the sporulation after incubation on
PCA increased from 60% to 93% on samples taken 7 to 21 days after inoculation, but decreased to 45% on material sampled after
35 days. A similar pattern was observed on leaves incubated at either 20° or 30°C. The sporulation ofC. rosea on leaf disks on PCA was not affected when the onset of high humidity occurred 0, 4, 8, 12 or 16 h after inoculation. However,
sporulation was reduced to 54–58% on leaflets kept for 20–24 h under dry conditions after inoculation and before being placed
on PCA. The fungus sporulated on 68–74% of the surface of leaf disks kept for up to 24 h at high humidity after inoculation,
but decreased to 40–51% if the high humidity period before transferral to PCA was prolonged to 36–48 h. The growth ofC. rosea on leaflets was reduced at low inoculum concentrations (103 and 104 conidia/ml) because of competition with indigenous microorganisms, but at higher concentrations (105 and 106 conidia/ml) the indigenous fungi were inhibited. Regardless of the time of application ofC. rosea in relation toB. cinerea, the pathogen’s sporulation was reduced by more than 99%. The antagonist was able to parasitize hyphae and conidiophores
ofB. cinerea in the leaf residues. AsC. rosea exhibited flexibility in association with rose leaves under a wide range of microclimatic conditions, and in reducingB. cinerea sporulation on rose leaves and residues, it can be expected to suppress the pathogen effectively in rose production systems. 相似文献
940.
P Sandín-España S Llanos J O Magrans J L Alonso-Prados & J M García-Baudín 《Weed Research》2003,43(6):451-457
Initial attempts to develop a hydroponic bioassay test for tepraloxydim failed due to lack of repeatability. Investigation of the fate of tepraloxydim in test media revealed that small residues of chlorine and chloramines present on distilled water cause fast degradation of the herbicide. Half‐life of tepraloxydim in the presence of a chlorine excess was determined to be DT50 < 5 s. Reaction with chloramines was slower (DT50 = 4.5 h). Finally, when this factor was eliminated by using water completely free of chlorine, the main process that took place was the isomerization of the oxime group (E vs. Z). However, the overall degradation was slow (DT50 = 17 days) and the hydroponic bioassay was optimized in the absence of chlorine. 相似文献