Rückstände von Carbendazim und anderen Fungiziden im Bienenhonig aufgrund der Blütespritzung von Winterraps

Zusammenfassung: 91 hessische Rapshonige der Erntejahre 2000 bis 2002 wurden auf Rückstände der zur Blütespritzung zugelassenen Fungizide Carbendazim, Iprodion, Metconazol, Tebuconazol und Vinclozolin untersucht. Dabei traten Tebuconazol und Vinclozolin vereinzelt in Mengen bis max. 0,018 mg/kg auf, Carbendazim hingegen in 35,2 % aller Proben und in Gehalten von bis zu 0,118 mg/kg. Im Mai 2002 wurden zwei isoliert gelegene Rapsflächen (9,8 bzw. 5,5 ha) während der Vollblüte mit 1 l/ha Derosal^® (360 g/l Carbendazim) bzw. mit 1,5 l/ha Folicur^® (251,2 g/l Tebuconazol) gespritzt. In jeweils sechs Honigproben von unmittelbar an den Flächen aufgestellten Völkern wurden Rückstandsgehalte von durchschnittlich 0,145 mg/kg (0,061 – 0,227 mg/kg) Carbendazim bzw. 0,018 mg/kg (<BG – 0,025 mg/kg) Tebuconazol ermittelt. Wirkstoffspezifische Eigenschaften des Carbendazims führen offensichtlich zu außergewöhnlich hohen Belastungswerten im Honig. Ungeachtet ihrer toxikologischen Relevanz veranlassten diese Befunde die Herstellerfirmen zu einer zwischenzeitlichen Vertriebseinstellung von Carbendazim und Thiopanatemethyl auf dem deutschen Markt.

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Residues of Carbendazim and other fungicides in honey due to blossom application in canola

Summary: During 2000 to 2002, 91 Hessian spring honeys from regions with an extended cultivation of canola were analysed for residues of the registered fungicides Carbendazim, Iprodion, Metconazol, Tebuconazol and Vinclozolin. The samples included 15 honeys from certified ecological apiaries.While Iprodion and Metconazol were not detected at all and Tebuconazol and Vinclozolin only sporadic with maximum levels of 0,018 mg/kg, Carbendazim was found in 35,2 % of the samples with up to 0,118 mg/kg. The eco honeys did not differ from the other samples.In May 2002 two isolated canola fields (9,8 resp. 5,5 ha) were treated with 1 l/ha Derosal^® (active in gredient: 360 g/l Carbendazim) in 600 l water/ha resp. with 1,5 l/ha Folicur^® (active ingredient: 251,2 g/l Tebuconazol) in 400 l water/ha during full blossom while a third field served as an untreated control. Three honey bee colonies were placed close to each field four days before treatment. From each hive, two samples of fresh honey were taken seven days after the treatment and analysed for residues of Carbendazim and Tebuconazol. While only one of six samples from the control field was contaminated with 0,080 mg/kg Carbendazim, each of the six honey samples from the Carbendazim treated field showed residues of Carbendazim (average: 0,145 mg/kg, range: 0,061 – 0,227 mg/kg) and five of six samples from the Tebuconazol treated field were positive for Tebuconazol (average: 0,018 mg/kg, range: <DL – 0,025 mg/kg).Due to its specific characters (slightly hydrophilic compared to other fungicides) a blossom application of Carbendazim can result in extremely high residue levels in honey. In the meantime, the manufacturers of Carbendazim and Thiophanatemethyl acknowledged these findings and, irrespectively of its toxicological relevance, stopped their deal with such products on the German market.

     

正确操作挤奶设备 降低牛奶体细胞数

牛奶体细胞数过高——我们应该做些什么？ 现在我们评定牛奶的质量,一般将体细胞数的最大值设定为400000.00／mL。如果体细胞数高于这个数,牛奶生产者收益就会立即受到损失。体细胞的出现一般是对乳腺组织受到感染或损伤的一种回应。这种感染必须得到很好治疗及去除病因后奶牛才能得到适当恢复,否则奶牛将受到长期的感染。保持对体细胞的有效控制,     

Ultrasonographic examination of the omasum, liver, and small and large intestines in cows with right displacement of the abomasum and abomasal volvulus

OBJECTIVE: To describe ultrasonographic appearance of the liver, small and large intestines, and omasum in cows with right displacement of the abomasum (RDA) and with abomasal volvulus (AV) and to determine whether RDA and AV can be differentiated on the basis of ultrasonographic findings. ANIMALS: 17 cows with RDA, 9 cows with AV, and 10 healthy control cows. PROCEDURES: A linear transducer was used to examine the abomasum, liver, omasum, and small and large intestines from the right side. Results-The liver was imaged less frequently in cows with RDA or AV, compared with control cows. In 9 cows with RDA or AV, the liver could not be imaged. The small intestine was imaged less frequently in cows with RDA or AV than in control cows; in cows with AV, the small intestine could not be imaged in the 8th, 9th, or 10th intercostal space. The large intestine was imaged less frequently in the 11th and 12th intercostal spaces and the cranial region of the flank in cows with RDA or AV. The omasum was also imaged less frequently in the 8th and 9th intercostal spaces in cows with RDA or AV. Cows with RDA or AV could not be differentiated on the basis of ultrasonographic findings. CONCLUSIONS AND CLINICAL RELEVANCE: Compared with control cows, cows with RDA and AV had changes in positioning and therefore extent of ultrasonographic imaging of the liver, omasum, and small and large intestines; however, these findings were not useful in differentiating between cows with RDA and AV.     

Effects of aspect and altitude on carbon cycling processes in a temperate mountain forest catchment

Context

Varying altitudes and aspects within small distances are typically found in mountainous areas. Such a complex topography complicates the accurate quantification of forest C dynamics at larger scales.

Objectives

We determined the effects of altitude and aspect on forest C cycling in a typical, mountainous catchment in the Northern Limestone Alps.

Methods

Forest C pools and fluxes were measured along two altitudinal gradients (650–900 m a.s.l.) at south-west (SW) and north-east (NE) facing slopes. Net ecosystem production (NEP) was estimated using a biometric approach combining field measurements of aboveground biomass and soil CO₂ efflux (SR) with allometric functions, root:shoot ratios and empirical SR modeling.

Results

NEP was higher at the SW facing slope (6.60?±?3.01 t C ha^?1  year^?1), when compared to the NE facing slope (4.36?±?2.61 t C ha^?1 year^?1). SR was higher at the SW facing slope too, balancing out any difference in NEP between aspects (NE: 1.30?±?3.23 t C ha^?1 year^?1, SW: 1.65?±?3.34 t C ha^?1 year^?1). Soil organic C stocks significantly decreased with altitude. Forest NPP and NEP did not show clear altitudinal trends within the catchment.

Conclusions

Under current climate conditions, altitude and aspect adversely affect C sequestering and releasing processes, resulting in a relatively uniform forest NEP in the catchment. Hence, including detailed climatic and soil conditions, which are driven by altitude and aspect, will unlikely improve forest NEP estimates at the scale of the studied catchment. In a future climate, however, shifts in temperature and precipitation may disproportionally affect forest C cycling at the southward slopes through increased water limitation.

     

Thermal weed control technologies for conservation agriculture—a review

Research and development activities on non-chemical weed control methods to date have mainly focused on mechanical and thermal applications. Selectivity in mechanical weed control is obtained using dynamically actuated harrows. Selectivity in thermal weed control is obtained through a certain heat tolerance of the crop. In conservation agriculture (CA), weed emergence is partially suppressed by constant soil cover with crops or cover crops. Large amounts of plant residues therefore remain on the soil, which make mechanical methods inefficient or difficult to implement. And thermal methods need to prevent not only crop damage but also fire from situationally dry plant residues. In this review, technologies that can potentially be used for in-crop weed control in CA are discussed. The technologies reviewed include spot-flaming, electric resistance heating, electromagnetic irradiation and steam/hot water application. Their evaluation focuses on efficiency and specificity (spatial precision). This review indicates that existing equipment does not fulfil the spatial precision required in CA and that further research and development is required on this topic. In particular, the authors suggest further research on the use of laser diodes, micro-flames and capacitive coupling of electric fields. It seems that the use of automated imaging systems for weed/crop differentiation is a prerequisite in CA to enable automatisation of weed control.     

Hydrochemical and stable isotopic assessment of nitrate contamination in an alluvial aquifer underneath a riverside agricultural field

Major ions and stable isotopic (δD_water, δ¹⁸O_water, δ¹⁵N_nitrate, δ¹⁸O_nitrate) measurements in concert with hydrochemical modeling were used in order to elucidate the sources and geochemical processes controlling nitrate contamination of shallow alluvial groundwater underneath a riverside agricultural field in the Buyeo area, Korea. Beneath vegetable fields in the sandy soil, the mean nitrate concentration of groundwater was 148.6 mg/L, which is significantly higher than in groundwater (mean 28.8 mg/L) beneath silty soils underneath rice paddy fields. Nitrogen isotope data indicate that synthetic fertilizers are the predominant source of groundwater nitrate in the study area. Denitrification during recharge through rice paddy soils appears to be responsible for the lower nitrate concentrations in groundwater beneath the silty soil zone. The relationship between nitrogen and oxygen isotope data of nitrate also suggests mixing of two different groundwater bodies with nitrates from the silt zone and the sand zone. Geochemical mass balance modeling on hydrochemical data indicates that various agricultural chemicals such as urea, lime, magnesium sulfate and potassium chloride dissolve in vegetable fields of the sandy zone, resulting in significant enrichment of various solutes such as K⁺, Ca²⁺, Mg²⁺, NO₃⁻, SO₄²⁻ and Cl⁻. As a consequence of over-utilization of synthetic nitrogen fertilizers, the sand zone is characterized by very high nitrate concentrations in the groundwater. This study suggests that a reduction of over-fertilization especially on vegetable fields in the riverside sand zone is required to minimize the nitrate contamination of groundwater. This study also shows that combination of geochemical and isotopic techniques with simple mass balance modeling provides information about the causes and processes of nitrate contamination of groundwater underneath a riverside agricultural field. The study also provides sustainable measures to optimize fertilization rate as an important basis of eco-friendly agriculture.     

In vitro absorption of dietary trans-resveratrol from boiled and roasted peanuts in Caco-2 cells

Previous studies on the transport and absorption of resveratrol (3,5,4-O-trihydroxystilbene) were done using the pure compound. In this study, the absorption of resveratrol in digested peanut micellar from boiled and roasted peanuts was investigated using a human intestinal Caco-2 cell monolayer. The amount transported and rate of transport of both resveratrol glycosides and its hydrolytic product were quantified by a reverse-phase high-performance liquid chromatography method with mass spectrometric detection. Four peaks were identified in the digested peanut micellar of both boiled and roasted peanuts: two resveratrol glycosides, one resveratrol diglycoside, and possibly an acylated resveratrol glycoside. Resveratrol from roasted peanut micellar had a higher transport rate than those from the boiled peanut. This implies that resveratrol from roasted peanut is better absorbed than from boiled peanut. Also, the rate of transport and amount of resveratrol transported were higher for the hydrolytic product than the nonhydrolyzed glycosides. This has strong implications for in vivo absorption as the enzymatic activity of gut microflora could enhance the bioavailability of β-glycosides of dietary polyphenols.     

Transendoscopic injection of poly-L-lactic acid into the soft palate in horses: A new therapy for dorsal displacement of the soft palate?

The purpose of this study was to establish a minimal invasive, transendoscopic technique for injection of poly-L-lactic acid into the free edge of the soft palate that can be performed on the standing sedated horse. Furthermore, whether the implant material induces an increase in fibrous tissue at the injection site, resulting in a greater rigidity of the soft palate, was determined.In 4 horses, the injection was performed bilaterally along the caudal margin of the soft palate, and the influence of the treatment on the soft palate function was determined. Clinical, radiographic and endoscopic examinations at rest were performed before and up to 168 days after injection according to a standardized examination protocol.In 6 horses, the implant material was injected unilaterally into the right half of the caudal margin of the soft palate. After clinical and endoscopic follow-up examinations, 2 horses each were killed 28, 84, and 168 days after the implantation procedure. At necropsy, macroscopic comparison of the treated and the untreated halves of the soft palate showed the influence on the size of the ostium intrapharyngeum and on the soft palate thickness. The localization of the implant material in the soft palate and the tissue response to the poly-L-lactic acid were evaluated histologically.Transendoscopic injection into the soft palate requires neither general anesthesia nor wound management, and it is noted for minimal tissue trauma. After injection, no alteration of the soft palate function was observed in horses with normal upper airway mechanics. One horse with intermittent dorsal displacement of the soft palate showed an improvement of the soft palate function for 112 days after implantation. No significant alteration in the size of the ostium intrapharyngeum was evident in any horse. Histologic assessment indicated the presence of implant material during the entire observation period of 168 days. The implant was accompanied by a granulomatous inflammation, and it was encapsulated by fibrous tissue. This may result in an increase in stiffness, and subsequent a greater rigidity of the soft palate, preventing it from displacement. The injection may therefore be considered an alternative to established therapies in horses showing dorsal displacement of the soft palate because of its unstable free edge.