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Macrorhabdus ornithogaster (M. ornithogaster) is an anamorphic ascomycetous yeast found only in the stomach of birds. Infection is often benign but has also been associated with disease in some species of birds under some circumstances. In vitro efforts to grow M. ornithogaster have been largely unsuccessful. In this report, multiple liquid and solid media of varying pH, sugar concentration, and fetal bovine serum (FBS) concentrations, incubated at various temperatures in room air or microaerophilic conditions, were examined for their ability to support the growth of M. ornithogaster, obtained from a budgerigar (Melopsittacus undulatus). Optimum growth conditions were found to be Basal Medium Eagle's, pH 3 to 4, containing 20% FBS, and 5% glucose or sucrose under microaerophilic conditions at 42 degrees C. Using these conditions, M. ornithogaster was repeatedly passaged without loss of viability. Polyclonal isolates of M. ornithogaster consistently assimilated glucose, sucrose, and trehalose. M. ornithogaster did not grow with prolonged exposure to atmospheric oxygen, but growth in microaerophilic conditions was moderately enhanced by preincubation with atmospheric oxygen for 24 hours. An isolate of M. ornithogaster was found to be infective to day-old chickens, reduce their rate of weight gain, and induce a mild to moderate heterophilic inflammation of the isthmus. M. ornithogaster was reisolated from the chicks 7 days after infection, fulfilling Koch's postulates. A 761-bp sequence of 18S rDNA from this isolate was compared to the originally reported M. ornithogaster sequence and was found to be 97% identical.  相似文献   
326.
To determine the inhibitory capacity of lactic acid bacteria due to the action of antagonistic substances, we tested 474 isolates of Lactobacillus from the crop and cecum of chickens against gram-positive and gram-negative indicator microorganisms by the spot-on-the-lawn and well-diffusion antagonism methods. Of the 474 isolates, 265 demonstrated antimicrobial activity against the indicator microorganisms. Isolates identified as L. reuteri, L. salivarius, or Lactobacillus spp. inhibited Enterococcus faecalis, E. faecium, Listeria monocytogenes, and Salmonella spp. but not L. casei, L. delbrueckii, L. fermentum, or L. helveticus by the well-diffusion simultaneous antagonism method under anaerobic incubation conditions. The antagonistic substances produced by some of the Lactobacillus isolates were inactivated after treatment by proteolytic enzymes, which suggested that the substances could be antimicrobial peptides or bacteriocins.  相似文献   
327.
The textural properties of cooked waxy rice cakes made from four waxy rice varieties including the unique varieties Kantomochi 172 (K172) and BC3 with the property of rapid hardening were analyzed by instrumental and sensory methods. For the instrumental analysis, a compression test, adhesiveness test, and tensile test were conducted. The waxy rice cakes made from K172 and BC3 showed significantly higher compressive force and resistance to break under tensile load. Significant difference in amylopectin chain‐length distribution was observed between each variety, and this difference strongly reflected the hardness of waxy rice cakes. The peak area ratio of amylopectin branch chains with 6–12 degrees of polymerization negatively correlated with the compressive force required for 50 and 80% strain. Sensory evaluation showed that the waxy rice cakes made from these varieties had a significantly harder, less stretchable, less smooth surface, whereas the scores for adhesiveness and ease to cut off (hagire) were preferable to those for other rice varieties.  相似文献   
328.
We have studied the quantitative analysis of potassium in agricultural materials by measuring the radioactivity of K4o by means of Radiation Counter since 1951. When the fundamental experiment was almost over and we were to begin the applications in fertilizers and crops, we found unexpectedly in May 1954, rain containing fission products presumably carried from H-bomb explosion test at Bikini. Temporarily abstaining from the experiment, we surveyed the degree of contamination of radioactive substances in crops, especially grapes, which are the main horticultural crop in this prefecture. Here, we explain the experimental data of the radioactivity in the grapes and the relations between the contamination of the artificial radioactivity and the potassium content in them.  相似文献   
329.
Although chinese yam plants are an important crop in Japan, relatively little is known about their content of the organic constituents. IZAWA and NATAKE (1,2,3) showed some aspects of the effect of the fertilizer treatment on the organic composition of chinese yam plants at various phase of their vegetation. Many reports on chinese yam plants have appeared; nevertheless, the nature of carbohydrate and nitrogen metabolism has remained unknown. However, there are a number of excellent reports (4, 5, 6) which directly or indirectly have a bearing on these biochemical phase in sweet Potato plants. Therefore, the objectives of the Present study were twofold : a) to determine the contents of sugars, starch, alcohol-insoluble solids, and various nitrogen constituents in sweet potato plants during growth as affected by mineral nutrition, and b) to compare the effect of mineral nutrition on sweet potato plants with its effect on chinese yam plants.  相似文献   
330.
Defective appearances, including white spotting (WS), tongue defect (TD), and nipple defect (ND), in Japanese Black cattle potentially lead to economic losses to farmers in Japan. We estimated genetic parameters of defective appearances using 553,433 records of Japanese Black heifer calves housed in the Kagoshima Prefecture. Variance and covariance were estimated using the Gibbs sampling algorithm. The estimated heritability ranged from 0.29 for TD to 0.76 for WS. Percent breeding value (%BV) estimates indicated high variation in WS and ND among sires, reflecting higher heritability. Furthermore, there was a positive linear relationship between the %BV estimate of a sire and the mean incidence rate of each defect in his female offsprings. TD was positively associated with other defects. Therefore, genetic factors strongly affect the incidence of defective appearances in Japanese Black cattle.  相似文献   
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