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The orchard of the Institute of Fruit Breeding of the German Federal Centre of Breeding Research on Cultivated Plants in Dresden-Pillnitz was highly affected by fire blight in 2003. Infected pomefruit trees were observed over a period of nearly 3 months. The first symptoms on pear trees were found on May 19th. The pathogen Erwinia amylovora was confirmed officially on May 26, and the last infected apple trees were detected the 11th of August. The infected trees had to be grubbed at the decision of the Phytopathological Authority. In total, 1164 apple and 478 pear trees were grubbed, including the entire pear collection of the gene bank. Of 35 wild species of pear, 49 accessions, eight accessions of six species each, showed infections. The apple collection of the gene bank included 33 wild species, with 365 accessions, and 845 cultivars and clones. Ten accessions of nine wild apple species and 81 cultivars/clones of these collections showed fire blight infection. The source of infection was the pear collection, and the distance from that source was important for the occurrence of infection. Field plots close to the pear collection had tree losses of 10–34%, while more distant plots had losses of 0–6%. Around 80% of the lost apple trees were detected and grubbed from 27th May to 11th June. Some of the cultivars bred in Dresden-Pillnitz, e.g. ‘Pilot’ and ‘Rekarda’, were affected by fire blight in most field plots, whereas most others were affected mainly only in plots adjacent to the infection source. A correlation of r=?0.72 could be calculated for rating in artificial shoot inoculations and percentage of trees of resistant cultivars lost. The cultivars ‘Pirol’, ‘Reanda’, ‘Remo’, ‘Rene’, ‘Renora’, ‘Resi’, and ‘Retina’ showed only a very low numbers of infected trees. No tree of ‘Rewena’ showed symptoms of fire blight. Despite a tendency to postblooming, only 8.9% of ‘Pinova’ trees had to be grubbed. 相似文献
3.
Monika Jamioł Jacek Wawrzykowski Marta Kankofer 《Reproduction in domestic animals》2021,56(7):1040-1049
One of the most important processes determining the proper course of gestation and its physiological termination in cows is the adhesion of epithelial cells allowing for direct contact of maternal and foetal parts of the placenta. Throughout pregnancy, placental cells are under strict hormonal control, which among others regulates the concentration and activity of specific proteins participating in the extracellular matrix remodelling of foetal membranes. The aim of the study was to evaluate the influence of progesterone and prostaglandin F2α on the adhesion of epithelial cells at early-mid pregnancy in cows. Additionally, the impact of selected hormones on anti-adhesive properties of decorin was evaluated. Caruncular epithelial cells were isolated from healthy cows during pregnancy, immediately after slaughter. Primary cell cultures derived from the 2nd and 4th month of gestation were used in the experiments. The viability of cells was assessed by MTT assay. The adhesion of cells to fibronectin was measured spectrophotometrically. The activity of metalloproteinases was confirmed by the metalloproteinase assay. Progesterone (10–5 and 10–7 mol/L) and prostaglandin F2α (10–4, 10–5 and 10–7 mol/L) increased the viability of bovine caruncular epithelial cells in the 2nd month of pregnancy. The treatment with prostaglandin F2α significantly reduced the number of adherent cells from the 2nd month of gestation at the doses of 10–4 and 10–5 mol/L. Both progesterone and prostaglandin F2α were shown to have an effect of decorin resulting in both a decrease in metalloproteinase activity and an increase in adhesion of cells to fibronectin. 相似文献
4.
The influence of crossbreeding on collagen solubility and tenderness of Infraspinatus and Semimembranosus muscles of semi‐intensively reared young bulls 下载免费PDF全文
Monika Modzelewska‐Kapituła Zenon Nogalski Aleksandra Kwiatkowska 《Animal Science Journal》2016,87(10):1312-1321
The aim of the present study was to investigate the effects of crossbreeding on collagen content and solubility, shear force (WBSF) and the eating quality of Infraspinatus (INF) and Semimembranosus (SM) muscles of young bulls and the relationships between collagen content and solubility, shear force and the eating quality of beef. The experimental material comprised muscles of crossbred young bulls (about 600 days old) of Polish Holstein‐Friesian (PHF) × Limousine (LM) (n = 10), PHF × Charolaise (CH) (n = 9), PHF × Hereford (HER) (n = 9) breeds. The crossbreeding influenced WBSF, aroma and taste, total, water‐soluble, acid‐soluble, total soluble and insoluble collagen content, as well as the acid‐soluble, total soluble and insoluble collagen proportions. WBSF was significantly negatively correlated with sensorial tenderness and water‐soluble collagen content. The eating quality of beef obtained from different crossbreds was similar; however, the meat from PHF × LM and PHF × HER bulls had lower WBSF values than PHF × CH bulls. © 2016 Japanese Society of Animal Science 相似文献
5.
Bodi D Fry H Schafft H Lahrssen-Wiederholt M Preiss-Weigert A 《Journal of agricultural and food chemistry》2012,60(28):6946-6952
Maduramicin is a coccidiostat authorized as feed additive in the European Union for chickens and turkeys for fattening but not for laying hens, considering the risk of residues in eggs. The unavoidable cross-contamination of non-target feed with coccidiostats is regulated by Commission Directive 2009/8/EC and resulting carry-over in food by Commission Regulation (EC) No. 124/2009. To verify the compliance of the maximum levels for maduramicin in feed (50 μg/kg) and eggs (2 μg/kg), the carry-over from feed into eggs was investigated. Diets containing 10, 30, and 50 μg of maduramicin/kg of feed were fed to laying hens. Feed, egg white, and yolk were analyzed by LC-MS/MS. Maduramicin residues were only detected in in egg yolk. Feeding the 10 μg/kg maduramicin diet resulted in maduramicin concentrations up to 2.5 μg/kg in whole eggs, already exceeding the maximum level. A carry-over rate of 8% maduramicin from feed into eggs was calculated. 相似文献
6.
Dennis Rubbenstroth Volker Schmidt Monika Rinder Marko Legler Victor Max Corman Peter Staeheli 《Veterinary microbiology》2014,168(2-4):318-323
Avian bornaviruses (ABV) are known to be the causative agent of proventricular dilatation disease (PDD) in parrots and their relatives (Psittaciformes). A broad range of ABV genotypes has been detected not only in psittacine birds, but also in other avian species including canary birds (Serinus canaria forma domestica) and Bengalese finches (Lonchura striata f. dom.), which are both members of the order songbirds (Passeriformes).During this study 286 samples collected from captive and wild birds of various passerine species in different parts of Germany were screened for the presence of ABV. Interestingly, only three ABV-positive samples were identified by RT-PCR. They originated from one yellow-winged pytilia (Pytilia hypogrammica) and two black-rumped waxbills (Estrilda troglodytes) from a flock of captive estrildid finches in Saxony. The ABV isolates detected here were only distantly related to ABV isolates found in passerine species in Germany and Japan and form a new genotype tentatively called ABV-EF (for “estrildid finches”). 相似文献
7.
Monika Jamioł Jacek Wawrzykowski Wioleta Mojsym Martina Hoedemaker Marta Kankofer 《Reproduction in domestic animals》2020,55(9):1093-1102
The activity of glycosidases is crucial for the function and biological activity of proteins conjugated with sugar moieties, which play an important role in adhesion of cells during attachment and detachment of the foetal membranes. The aim of study was to describe the ability of bovine placental tissues to break down O-glycosidic bonds in different glycoproteins by the determination of activity of β-galactosidase, α-l-fucosidase, β-N-acetyl-hexosaminidase and sialidase in early–mid-pregnancy as well as at parturition with released and retained foetal membranes. Moreover, the availability of substrates for these glycosidases in placental homogenates was evaluated. Placental samples were collected from pregnant (2–4 months) cows in slaughterhouse (n = 8) as well as during Caesarean section and divided into released foetal membranes (n = 8) and retained foetal membranes (n = 8). Tissue homogenates were subjected to spectrofluorimetric and spectrophotometric determinations of enzyme activities as well as electrophoretic separations. Enzyme activities expressed changes within examined time with significant (p < .05) differences between pregnancy and physiological parturition in β-N-acetyl-hexosaminidase and α-l-fucosidase in foetal part of placenta while in maternal part only in the latter one. Decreasing tendency in enzyme activity was noticed in foetal part of retained samples in comparison with released ones with significant (p < .05) differences in α-l-fucosidase activity. The analysis of staining of sugar moieties attached to selected proteins depicted availability of sugar molecules in examined tissues, but their patterns differed between samples. In conclusion, sugar moieties in conjugated proteins express changes in the course of pregnancy which is reflected by the alterations in activities of placental glycosidases. 相似文献
8.
Monika Go?mann Alexandra Scholz Frank Hennig Susanne von Bargen Carmen B��ttner 《Gesunde Pflanzen》2011,63(4):175-182
Fusarium oxysporum and Fusarium proliferatum are important causal agents of crown and root rot of asparagus. In order to detect differences in pathogenicity and aggressiveness, two F. proliferatum and five F. oxysporum single spore isolates from asparagus spears from plantings in Austria and Germany, 55 pure cultures of F. oxysporum from asparagus roots from a planting in Hesse, Germany, and a single F. oxysporum isolate from an asparagus shoot collected in Austria were evaluated in a 28-day quick test on Hoagland??s agar in glass culture tubes. Plantlets were inoculated with spore suspensions from each respective isolate after 14 days of growth under sterile, controlled conditions in a growth chamber. A severity scale was used to assess symptoms on roots two weeks after inoculation. The effects of the single-spore isolates on root and shoot fresh weights of the plantlets were also determined. The pathogenicity of the majority of the F. proliferatum and F. oxysporum isolates included in this study was confirmed. Inoculation with pure and single-spore cultures resulted in elevated disease severity in comparison to non-inoculated controls. In particular, the two F. proliferatum isolates were found to be more aggressive than the F. oxysporum isolates. Moreover, all single spore isolates caused a reduction in fresh weight of roots and shoots in comparison to the controls. With respect to differences among asparagus cultivars, ??Ramos??, was found to be more susceptible than ??Ravel??. Overall, the quick test method was found to be capable of evaluating the pathogenicity and aggressiveness of the tested F. oxysporum and F. proliferatum isolates towards asparagus within 28 days. 相似文献
9.
Favrot C Steffan J Seewald W Hobi S Linek M Marignac G Olivry T Beco L Nett C Fontaine J Roosje P Bergvall K Belova S Koebrich S Pin D Kovalik M Meury S Wilhelm S 《Veterinary dermatology》2012,23(1):45-50, e11
Hypersensitivity dermatitides (HD) are commonly seen in cats, and they are usually caused by environmental, food and/or flea allergens. Affected cats normally present with one of the following clinical reaction patterns: head and neck excoriations, usually symmetrical self-induced alopecia, eosinophilic skin lesions or miliary dermatitis. Importantly, none of these clinical presentations is considered to be pathognomonic for HD skin diseases, and the diagnosis of HD is usually based on the exclusion of other pruritic diseases and on a positive response to therapy. The objectives of this study were to propose sets of criteria for the diagnosis of nonflea-induced HD (NFHD). We recruited 501 cats with pruritus and skin lesions and compared clinical parameters between cats with NFHD (encompassing those with nonflea, nonfood HD and those with food HD), flea HD and other pruritic conditions. Using simulated annealing techniques, we established two sets of proposed criteria for the following two different clinical situations: (i) the diagnosis of NFHD in a population of pruritic cats; and (ii) the diagnosis of NFHD after exclusion of cats with flea HD. These criteria sets were associated with good sensitivity and specificity and may be useful for homogeneity of enrolment in clinical trials and to evaluate the probability of diagnosis of NFHD in clinical practice. Finally, these criteria were not useful to differentiate cats with NFHD from those with food HD. 相似文献
10.
Many different fungi grow indoors as mold in the presence of moisture. Some of these fungi can cause allergic or toxic reactions, while a few may cause infections in susceptible individuals. A comprehensive treatment of this complex topic would take volumes. Therefore many groups search for alternative management strategies of these fungi. It has been tested if the growth of nine fungi (Alternaria alternata, Botrytis cinerea, Cladosporium herbarum, Fusarium culmorum, F. solani, F. verticillioides, Mucor sp., Penicillium sp. and Trichoderma sp.) which are common in interior buildings could be inhibited by mixing lignin into wall plaster. In maltextract agar lignin concentrations above 10 % inhibited mould growth except for Penicillium sp. However, none of the mould species showed and degradation of lignin. Further investigations on a lignin-plaster-agar, which contained only plaster as nutrient and had a high pH at 8, showed no inhibition on the tested fungi (Alternaria alternata, Fusarium verticillioides, Mucor sp., Trichoderma sp. and Penicillium sp.) at concentrations up to 5 %. Higher lignin concentrations lead to insufficient quality of building materials, e. g. cracking. Furthermore the color of the building materials turned from greyish-white in an exotherm reaction into brown, become not any more suitable for construction purposed. 相似文献