Identification on commercialized products of AFLP markers able to discriminate slow- from fast-growing chicken strains

The European chicken meat market is characterized by numerous quality marks: "Label de Qualité Wallon" in Belgium, "Label Rouge" in France, denominations of geographical origin, organic agriculture, etc. Most of those certified productions have specifications requiring the use of slow-growing chicken strains. The amplified fragment length polymorphism (AFLP) technique has been used to search molecular markers able to discriminate slow-growing chicken strains from fast-growing ones and to authenticate certified products. Two pairs of restriction enzymes (EcoRI/MseI and EcoRI/TaqI) and 121 selective primer combinations were tested on individual DNA samples from chicken products essentially in carcass form that were ascribed as belonging to either slow- or fast-growing strains. Within the resulting fingerprints, two fragments were identified as type-strains specific markers. One primer combination gives a band (333 bp) that is specific for slow-growing chickens, and another primer pair generates a band (372 bp) that was found to be characteristic of fast-growing chickens. The two markers were isolated, cloned, and sequenced. The effectiveness and the specificity of the two interesting determinants were assessed on individuals of two well-known strains (ISA 657 and Cobb 500) and on commercialized products coming from various origins.     

Horseradish peroxidase-catalyzed cross-linking of feruloylated arabinoxylans with beta-casein

Heterologous conjugates of wheat arabinoxylan and beta-casein were prepared via enzymatic cross-linking, using sequential addition of the arabinoxylan to a mixture of beta-casein, peroxidase, and hydrogen peroxide. The maximal formation of adducts between the beta-casein and the feruloylated arabinoxylan was reached at a protein-to-arabinoxylan ratio of 10:1, in combination with a molar ratio hydrogen peroxide to substrate of 2:1 and a molar protein-to-enzyme ratio between 10(2) and 10(4). The protein-arabinoxylan adducts were separated from the arabinoxylan homopolymers by size exclusion and anion exchange chromatography. The molar ratio protein:arabinoxylan in the purified conjugates varied between 0.1 and 5.6. This is the first report on the large-scale enzymatic preparation of heterologous protein-arabinoxylan conjugates.     

Freshwater liming

Operational liming of surface waters is part of Sweden and Norway's strategy to counteract freshwater acidification caused by air pollutants. Smaller scale liming efforts are performed as research or experimental programs in other countries. Yearly, approx. 300,000 tons of fine-grained limestone (CaCO₃) is spread in lakes and streams and on wetlands to raise the pH in surface water at a cost of approximately 40–50 million $US. The chemical target is set by the biological goals and objectives. A total of over 11,000 lakes and streams are treated on a continuing basis. Dose calculations consider pH, inorganic monomeric Al, dissolved organic matter and the necessary buffering. Lake liming, limedosers at streams and terrestrial liming are used. A mix of different liming techniques is often preferred to get an optimal result. The vast majority of changes are desirable and expected Undesirable effects may appear and damaged wetlands are probably the most serious ones. Cost-benefit analysis show that liming may be profitable for the society. Recovery of the systems can take up to 10–20 years. Liming will in the long run restore the ecosystems but will not make them identical to what may be the original ones. In some cases, complementary measures, e.g. facilitation of recolonization, are necessary to enhance recovery. Reduced emissions of acidifying pollutants according to signed protocols will decrease the need for liming, but still liming is needed for several decades in large regions to preserve biodiversity.     

Podzolization as a deferralitization process: a study of an Acrisol–Podzol sequence derived from Palaeozoic sandstones in the northern upper Amazon Basin

Morphological, geochemical and mineralogical studies were carried out in a representative soil catena of the low‐elevation plateaux of the upper Amazon Basin to interpret the steps and mechanisms involved in the podzolization of low‐activity clay soils. The soils are derived from Palaeozoic sandstones. They consist of Hydromorphic Podzols under tree savannah in the depressions of the plateaux and predominantly of Acrisols covered by evergreen forest elsewhere. Incipient podzolization in the uppermost Acrisols is related to the formation of organic‐rich A and Bhs horizons slightly depleted in fine‐size particles by both mechanical particle transfer and weathering. Weathering of secondary minerals by organic acids and formation of organo‐metallic complexes act simultaneously over short distances. Their vertical transfer is limited. Selective dissolution of aluminous goethite, then gibbsite and finally kaolinite favour the preferential cheluviation of first Fe and secondly Al. The relatively small amount of organo‐metallic complexes produced is related to the quartzitic parent materials, and the predominance of Al over Fe in the spodic horizons is due to the importance of gibbsite in these low‐activity clay soils. Morphologically well‐expressed podzols occur in strongly iron‐depleted topsoils of the depression. Mechanical transfer and weathering of gibbsite and kaolinite by organic acids is enhanced and leads to residual accumulation of sands. Organo‐metallic complexes are translocated in strongly permeable sandy horizons and impregnate at depth the macro‐voids of embedded soil and saprolite materials to form the spodic Bs and 2BCs horizons. Mechanical transfer of black particulate organic compounds devoid of metals has occurred later within the sandy horizons of the podzols. Their vertical transfer has formed well‐differentiated A and Bh horizons. Their lateral removal by groundwater favours the development of an albic E horizon. In an open and waterlogged environment, the general trend is therefore towards the removal of all the metals that have initially accumulated as a response to the ferralitization process and have temporarily been sequestrated in organic complexes in previous stages of soil podzolization.     

Dermendung Kriegsbesch?digter Forstarbeiter

Ohne Zusammenfassung     

Studies on the sterile-male technique as a means of control of Adoxophyes orana (Lepidopt., Tortricidae). 1. Problems of mass rearing (crowding effects)

Almost all larvae ofAdoxophyes orana F.R. mature if they are individually confined in vials. In gregarious culture, 2 or 4 larvae per vial, growth is retarded and many larvae die because of frequent fighting. This aggression results from the biggest larvae holding other larvae off the food. Retarded development was not due to optical or olfactory causes, but to food deprivation. In mass rearing the setback can be partly overcome by adding plastic strips that increase the cover for the larvae in rearing boxes.Samenvatting Massakweken vanAdoxophyes orana zijn noodzakelijk voor de ontwikkeling van een steriele-mannetjesprogramma ter bestrijding van deze plaag. In kweken in buisjes werd een agressief gedrag van de opgroeiende rupsen waargenomen wanneer zich meer dan 1 rups per buis bevond. Hierdoor werd de groeisnelheid vertraagd en trad bij 4 larven per buis veel sterfte op (Fig. 1 en 2, Tabel 1). Deze groeieffecten hadden geen optische of olfactorische oorzaak. Wanneer de larven meer ruimte kregen nam wel de mortaliteit af (Tabel 3) maar niet de groeivertraging (Tabel 4). Verstoring van de larven beïnvloedde hun groei nadelig (Tabel 5 en 6). De groeivertraging is echter voor het grootste deel te wijten aan hongeren (Tabel 7) doordat in de kweek de grotere larve de toegang tot het voedsel ontzegt aan de kleinere.In massakweken kan de hieruit voortvloeiende groeivertraging en mortaliteit worden verminderd door plastic strips in de kweekbakken te plaatsen waardoor het aantal schuilplaatsen voor de larven toeneemt.     

Intestinal permeability to macromolecules in piglets infected with transmissible gastroenteritis virus

The permeability of the intestine of specific pathogen free piglets was investigated by measuring the concentration of 125-I in the blood after oral administration of 125-I polyvinylpyrrolidone (125-I PVP, MW=40 000 Da) and the concentration of 131-I in the faeces after intravenous administration of 131-I porcine albumin (131-I PA, MW=68 000 Da). The tests were performed one day before and up to two days after the piglets were infected with the Miller strain of transmissible gastroenteritis (TGE) virus. Biopsies of the jejunum were taken at the end of the experiment and blood samples were taken six-hourly. The piglets became anorexic and had diarrhoea 12 hours after infection; the packed cell volume decreased and the concentrations of urea and total serum proteins increased slightly after infection. However, the marked villous atrophy was not accompanied by an increased permeability of the intestine to PVP or PA.     

Soil fumigation and crop rotation to control spraing disease in potatoes

Growing resistant potato cultivars is of little help in avoiding damage by spraing, because of regionally differing strains of tobacco rattle virus and of special requirements of the processing industry. On soil, fumigated in 1971 during autumn with a solution of dichloropropene-dichloropropane (660 g/l) at 250 l/ha, the vectorsTrichodorus spp., were effectively controlled and the tuber disorder did not appear in the next year's potato crop. But potatoes from the treated plots had an unacceptable off-flavour. In the second crop after treatment, control was still good and there was no difference in flavour between potatoes from treated and untreated plots. Disease incidence was significantly lower after spring barley than after sugarbeet, maize, or potatoes.