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1.
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   
2.
Ultrasonography is a valuable tool for the evaluation of neoplastic lesions in the dog and there is a growing interest in the use of this technique for the stadiation of canine mammary tumours. An accurate assessment of small sized nodules facilitates the stadiation of the mammary lesions and helps the clinician in the choice of the most indicated surgical therapy. The aim of this study was to identify those ultrasound criteria that may be useful in discriminating between benign and malignant lesions of small size (diameter smaller than 2 cm). Sixty-two nodules, < 2 cm in larger diameter, belonging to thirty-five bitches presented between January 2012 and February 2014 were evaluated. Tumours were observed by conventional ultrasound and assessed for: shape (regular-irregular), limit (defined-ill-defined), margins (regular-irregular), echogenicity (hypoechoic-isoechoic-hyperecoic), echotexture (homogeneus-heterogeneus), presence of hyperecoic halo, distal acoustic enhancement or shadowing and surrounding tissue alterations. Among the alterations in surrounding tissues, the disruption of the glandular tissue and the increase in echogenicity of the peritumoral tissues were assessed. Thereafter, bitches were subjected to mastectomy and nodules were evaluated histologically. None of the ultasound criteria considered in the current study showed a statistically significant relation with malignancy, except for the presence of alterations in the tissue surrounding the nodules. According to our results, this characteristic may indicate malignancy, however its subjectivity may affect the applicability in clinical practice. In conclusions, conventional ultrasound in bitches had a limited ability in discriminating benign and malignant mammary gland neoplastic lesions of small size (diameter?<?2 cm).  相似文献   
3.
Oleosin, a unique structural protein anchoring onto the surface of seed oil bodies by its central hydrophobic domain, stabilizes these lipid-storage organelles as discrete entities. Stable artificial oil bodies have been successfully constituted with native or recombinant oleosins. In this study, recombinant sesame oleosin with 12 residues stepwise truncated from its central hydrophobic domain of 72 residues was overexpressed in Escherichia coli, was purified to homogeneity, and was used for the constitution. Artificial oil bodies constituted by truncated oleosins with the central hydrophobic domain longer than 36 residues were as stable as native sesame oil bodies, and those constituted by truncated oleosins lacking more than half of the original central hydrophobic domain inclined to coalesce upon collision or aggregation.  相似文献   
4.
Rearing of goats under communal farming conditions is characterised by high kid mortality and low weaning percentages. A survey was conducted to determine farmers’ perceptions on the causes of kid mortality during summer under the communal farming system in Nkonkobe Local Municipality in the Eastern Cape, South Africa. This was done by administering questionnaires to a total of 162 respondents in 14 villages around Nkonkobe Local Municipality. The study showed that majority of farmers (75 %) keep flock sizes of less than 10 goats and kids, and this indicates that goat production in Nkonkobe Local Municipality is suppressed. According to the farmers, diseases (89 %), endo-parasites (72 %) and ecto-parasites (68 %) were perceived as the major causes of kid mortality. Other causes reported include starvation (15 %), extreme weather conditions (28 %), abortion (7 %), theft (35 %), diarrhoea (43 %), accidents (10 %) and wounds (9 %). The low number of goats could be attributed to high mortalities. It was also found that all causes reported by farmers played a role in high kid mortality in Nkonkobe Local Municipality. However, the causes which require more emphasis to formulate extension support were tick-borne diseases and parasites. This study provided baseline information on possible causes of kid mortalities in Nkonkobe Local Municipality. There is, however, a need to conduct further studies to determine actual causes of high kid mortalities so as to develop preventive strategies that would minimize kid mortality for good economic returns.  相似文献   
5.
The digestibility of various diet components as protein sources for common carp, Cyprinus carpio L., at 500–800 g was studied by using an inert marker in the feed and collecting the faeces by stripping. Protein in fish meal (83.8%) and soybean meal (69.8%) were significantly more digestible than that of poultry meal (47.2%). Energy digestibility tests gave the following results: fish meal 93.4%, soybean meal 74.7% and poultry meal 63.9%. It was evident that the ability of carp to digest proteins is very high, and that they can utilize proteins as the main component of their diet.  相似文献   
6.
We demonstrate the protection of one bit of quantum information against all collective noise in three nuclear spins. Because no subspace of states offers this protection, the quantum bit was encoded in a proper noiseless subsystem. We therefore realize a general and efficient method for protecting quantum information. Robustness was verified for a full set of noise operators that do not distinguish the spins. Verification relied on the most complete exploration of engineered decoherence to date. The achieved fidelities show improved information storage for a large, noncommutative set of errors.  相似文献   
7.
The long-term effects of a toltrazuril treatment against natural Eimeria bovis and/or Eimeria zuernii infections were investigated in comparison with diclazuril and untreated controls on two dairy (Italian Friesian breed) and two beef (Chianina breed) farms. At each trial site, 30 calves were allocated into three groups of 10 calves each: T (treated with toltrazuril), D (treated with diclazuril) and C (left untreated). For 40 weeks post-treatment, the calves were weighed and examined clinically and parasitologically. The oocyst counts as well as the number of scour days were significantly lower in the T group than in the D and C groups. Final bodyweights and body condition scores of the T group exceeded those of groups C and D. The results confirmed that toltrazuril was highly efficacious, safe and provided productive benefits in dairy and beef calves.  相似文献   
8.
Enterococci are important inhabitants of animal intestine and are widely used in probiotic products. A potentially successful probiotic strain is expected to have several desirable properties in order to be able to exert its beneficial effects. Forty enterococcal isolates from dog faeces were tested for characters believed to be important for probiotic strains; bacteriocin production, resistance or tolerance to antibiotics, low pH, bile tolerance and adhesive activity. The total count of enterococci was found to be 3.3-7.3log(10)CFU/g of faeces. Most identified strains were Enterococcus faecium. All strains were sensitive to vancomycin, ampicillin, penicillin and chloramphenicol. Thirty-three percentage of strains were resistant to erythromycin and 28% to tetracycline. Among 40 isolates, 75% showed a broad inhibitory spectrum only against Gram-positive indicator bacteria. Seven strains with broad bacteriocin activity were selected for further assays. In the presence of 1% bile, the survival rate of selected strains ranged between 72 and 98%. Survival of strains at pH 3.0 was found in the range between 76 and 87% after 3h. The adhesion of the tested strains to intestinal mucus ranged from 4 to 11% for canine mucus and from 5 to 8% for human mucus. E. faecalis EE4 and E. faecium EF01 showed the best probiotic properties. It indicates that they could be used as new candidate probiotic strains after in vivo testing.  相似文献   
9.
The protective effect of Enterococcus faecium EF55 in chickens challenged with Salmonella enterica serovar Enteritidis phage type 4 (SE PT4) was assessed. The antibacterial effect on the bacterial microflora in the small intestine in relation to white blood cell count, phenotyping of peripheral blood and intestinal lymphocytes, functional activity of lymphocytes and phagocytes and mucin quantitation were investigated. Day-old chicks (85) were randomly divided into four groups. The probiotic group (EF) and Salmonella + probiotic group (EFSE) received E. faecium EF55 (109 CFU – 3 g/group/day) for 21 days. The Salmonella group (SE) and EFSE group were infected with Salmonella Enteritidis (108 CFU in 0.2 ml PBS) in a single dose per os on day four of the experiment. The control group chicks (C) were fed a commercial diet without added bacteria. Supplementation of EF55 in the diet of the chickens in the EFSE group, challenged with S. Enteritidis, caused the density of the intestinal mucin layer to increase significantly in non-specific regions (duodenum and jejunum), but decrease significantly in target regions (caeca) for S. Enteritidis. Probiotic treatment also appeared to result in a significantly higher number of lymphocytes in peripheral blood and a tendency to increase CD3, CD4, CD8, and IgM positive cells 3 days post-infection with S. Enteritidis. The results demonstrated an antibacterial effect and suggested that EF55 had a moderating effect on intestinal mucin production and leukocytic response in the early phase of S. Enteritidis infection.  相似文献   
10.
In the previous work conducted, it was found that the root extract of Elephantorrhiza elephantina (Bruch.) Skeels. exhibited good anthelmintic efficacy against eggs and larvae of Haemonchus contortus. This study was therefore undertaken to screen fractions of the extracts of E. elephantina for their anthelmintic activity against adult H. contortus using a bioactivity-guided assay. The adult worm bioassay was conducted using aqueous, hexane and ethyl acetate fractions of the plant extracts at concentrations of 0.312, 0.625, 1.25, 2.5, 5 and 10 mg/ml in vitro. Albendazole and distilled water were used as positive and negative control, respectively. In vitro treatment of adult worms revealed concentration and time-dependent efficacy of the fractions of E. elephantina. The aqueous and ethyl acetate fractions showed a highly significant (P < 0.05) motility inhibition at concentrations of 2.5 mg/ml and above after 6 h of exposure, while the hexane fraction showed a significant (P < 0.05) motility inhibition at concentrations of 5 mg/ml and above. After 30 h of exposure, all the fractions showed insignificant (P > 0.05) inhibition of motility. The fractions of E. elephantina also showed mortality indexes that were not significantly different to each other, as well as to the commercial drug (albendazole). Overall, the ethyl acetate and the aqueous fractions were found to possess the highest anthelmintic activity. We therefore recommend future studies to further investigate effective dosages of these fractions in vivo, as well as a full investigation into the compounds responsible for the biological activity.  相似文献   
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