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71.
The phylogenetic relationships among Erwinia amylovora biovar 4 (the pathogen of bacterial shoot blight of pear in Japan), other biovars of E. amylovora, and Erwinia pyrifoliae were investigated using the sequences of 16S rRNA, gyrB, and rpoD genes. The tested isolates formed two distinct monophyletic groups in the phylogenetic trees constructed based on the gyrB gene, rpoD gene, or a combination of the three genes: group 1 contained E. amylovora biovars 1, 2, and 3; group 2 contained E. amylovora bv. 4 and E. pyrifoliae. This phylogenetic analysis showed that E. amylovora bv. 4 was more closely related to E. pyrifoliae than to other biovars of E. amylovora. The nucleotide sequence data reported are available in the DDBJ/EMBL/GenBank databases under the accession numbers AB242876 to AB242925.  相似文献   
72.
Invasion of apple fruit by Erwinia amylovora from fruit-bearing twigs through the abscission layer at fruit maturation was examined. Erwinia amylovora (ca. 105 cfu) tagged with bioluminescence genes from Vibrio fischeri was deposited in artificial wounds on fruit-bearing twigs of apple trees grown in a containment greenhouse on September 22, 27, or October 5, 2004. On October 22, 176 apples were harvested and cut horizontally in half. The upper halves were stamped on plates of selective medium, and the lower halves were flooded with iodine solution to assess maturity. All fruit were symptomless and fully mature. The pathogen was recovered from 19 (10.8%) apples. The result showed that if at least ca. 105 cfu of E. amylovora are present in fruit-bearing twigs at the time of fruit maturation, the bacteria can pass through the abscission layer into the fruit, even though the mature fruit lack symptoms.  相似文献   
73.
We evaluated the effects of various dietary blood meal levels on the growth performance and body composition of pirarucu (Araipama gigas) juveniles. Fish (8.5 ± 0.4 g) were stocked into 24 tanks and fed for 60 days with eight isoproteic diets, having 0% to 21% incorporation of blood meal. Fish increased weight by six to 15 times from their initial weight. The highest body weights (117–135 g), growth rates (4%–5% BW/day), and protein retentions (19%–20%) were observed in fish fed 0% to 6% blood meal. Feed intake increased from 2.9% to 4.4% BW/day with increasing blood meal level. Feed conversion ratio (FCR: 1.0–1.1) did not vary among groups fed 0% to 6% blood meal (P < 0.001). However, when fish were fed more than 6% blood meal, FCR (1.3–1.7) and protein retention (11.1–13.7) deteriorated sharply. Lipid (7.7–11.7%) and energy (18.7–21.2 kJ/g) content increased with increasing blood meal levels up to 9%.  相似文献   
74.
75.
Akifumi SHIMIZU  Shinji KAWASAKI 《水稻科学》2009,16(4):247-247,J0001,248-253
High-density linkage maps are essential tools for genome analysis of various biological traits. Our developed compact multi-gel system, HEGS (high efficiency genome scanning) is a high-throughput and high-cost-performance electrophoresis apparatus. Using this system, a high-density (average interval 2.3 cM) map with 1 065 AFLP and 63 SSR markers was constructed from recombinant inbred lines of a japonica and indica hybrid in just two months of electrophoreses by a single person. More than 50% of the mapped AFLP markers were commonly polymorphic for several combinations between japonica and indica rice and 15% were applicable for genetically closer crosses between upland and lowland types of japonica rice. This system can be used for rapid analyses of all kinds of markers.  相似文献   
76.
Black lesions on shoots of European pear trees observed in an orchard in Yamagata Prefecture in May 2007 were suspected to be caused by a bacterial pathogen. The surface of the colonies isolated on a high sucrose medium did not have the crater morphology that is characteristic of E. amylovora bvs. 1–3, and a specific DNA fragment was amplified from the isolates in the PCR using the EprpoD primer set. The partial sequences of the 16S rRNA gene placed the isolates in the genus Erwinia. The isolates differed serologically from E. amylovora biovars and E. pyrifoliae in an Ouchterlony double-diffusion test although their bacterial properties suggested that they are closely related to E. amylovora biovars and E. pyrifoliae. In a DNA–DNA hybridization test, the relatedness between the isolates and E. amylovora biovars or E. pyrifoliae did not exceed 70% level, indicating that they are independent species. Thus, the isolates belongs to the genus Erwnia but are not E. amylovra or E. pyrifoliae. After succulent pear shoots were injected with bacterial suspensions (109, 108, 107 and 10cfu/ml) of the isolates, lesions formed with 109 and 10cfu/ml, but the disease incidence with 10cfu/ml was much lower than with E. amylovora and E. pyrifoliae. Virulence of the present isolates is thus thought to be very weak. On the basis of these results, we consider that this is a new shoot disease of European pear. In the 2007 season, all affected trees were pulled out after harvest. No symptoms have been observed in field surveys since the fruitlet season in 2007.  相似文献   
77.
We estimated the nitrogen (N), phosphorus (P), potassium (K) and magnesium (Mg) excretion factors of broiler and layer chickens in Japan, using two approaches and the latest data available. In the top‐down approach, we determined the nutrient amounts in the feeds and those in the products (i.e. the liveweight gain, eggs), and the national nutrient excretions were determined as the difference between these amounts. We then calculated the nutrient excretion factors by dividing the national excretions by the number of animals. In the bottom‐up approach, we calculated the amounts of nutrients in the feed and product per head using productivity parameters (feed conversion ratio, etc.). The differences between these amounts were considered the nutrient excretion factors. The average nutrient excretion factors of broilers (g/day/head) estimated using the top‐down and bottom‐up approaches were: N, 1.40 and 1.87; P, 0.36, 0.50; K, 0.54, 0.77; Mg, 0.13, 0.18, respectively. The excretion factors obtained by the top‐down approach can be used to calculate the national/regional excretions. The two approaches resulted in almost the same excretion factors for layers, and the average nutrient excretion factors of layers (g/day/head) estimated were: N, 2.20; P, 0.55; K, 0.68; Mg, 0.23. The estimated excretion factors for N (only) are smaller than the reported factors.  相似文献   
78.
OBJECTIVE: To determine effects of increased dietary protein and decreased dietary carbohydrate on hematologic variables, body composition, and racing performance in Greyhounds. ANIMALS: 8 adult Greyhounds. PROCEDURE: Dogs were fed a high-protein (HP; 37% metabolizable-energy [ME] protein, 33% ME fat, 30% ME carbohydrate) or moderate-protein (MP; 24% ME protein, 33% ME fat, 43% ME carbohydrate) extruded diet for 11 weeks. Dogs subsequently were fed the other diet for 11 weeks (crossover design). Dogs raced a distance of 500 m twice weekly. Rectal temperature, hematologic variables before and after racing, plasma volume, total body water, body weight, average weekly food intake, and race times were measured at the end of each diet period. RESULTS: When dogs were fed the MP diet, compared with the HP diet, values (mean +/- SD) differed significantly for race time (32.43 +/- 0.48 vs 32.61 +/- 0.50 seconds), body weight (32.8 +/- 2.5 vs 32.2 +/- 2.9 kg), Hct before (56 +/- 4 vs 54 +/- 6%) and after (67 +/- 3 vs 64 +/- 8%) racing, and glucose (131 +/- 16 vs 151 +/- 27 mg/dl) and triglyceride (128 +/- 17 vs 104 +/- 28 mg/dl) concentrations after racing. CONCLUSIONS AND CLINICAL RELEVANCE: Greyhounds were 0.18 seconds slower (equivalent to 0.08 m/s or 2.6 m) over a distance of 500 m when fed a diet with increased protein and decreased carbohydrate. Improved performance attributed to feeding meat to racing Greyhounds apparently is not attributable to increased dietary protein and decreased dietary carbohydrate.  相似文献   
79.
In Annex 1 countries, nitrous oxide (N2O) emissions from swine and poultry excreta have been calculated and the N2O reduction potential of each country by using amino acids in feed could also be calculated, then a comparison made among the countries. The N2O reduction rates were approximately 25% for these Annex 1 countries and amino acids were able to make a large contribution to that reduction. Greenhouse gases (GHG) which are N2O combined with methane (CH4) were estimated to reduce by 24.8% in Japan when amino acids were introduced into the feed, but only a 7.2% reduction was estimated in France. Purification, which is mainly used for manure treatment in Japan, emits much more N2O and less CH4, whereas the liquid system which is mainly used in France emits more CH4 and less N2O based on the emission factors from the United Nations Framework Convention on Climate Change data base. Changing the French manure treatment system to the Japanese style with amino acids in feed would reduce GHG emissions by 23.4%. Reduction of the arable land use in Japan by changing crop formulations supported by adding amino acids to feed was also quantified as about 10% and led to an increase in the production of meat using the same arable land area.  相似文献   
80.
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