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81.
Kazutaka Kido Masaru Hasegawa Hiroyuki Matsumoto Masaki Kobayashi Yuichi Takikawa 《Journal of General Plant Pathology》2010,76(3):208-218
Ninety-six strains of Pantoea ananatis were isolated from 14 plant species including melon, rice, tea and other crops of economic importance. They were classified
into three groups (group I, II, III) based on a welsh onion stabbing assay, tobacco infiltration test, and polymerase chain
reaction to detect indole acetic acid (IAA) biosynthesis genes (iaaM and iaaH) and a cytokinin biosynthesis gene (etz). Group Ι strains were characterized as causing significant blight symptom on welsh onion and inducing a hypersensitive response
(HR)-like reaction on tobacco leaves after 36–48 h and encompassed 20 isolates from foxtail millet, hydrangea, pineapple,
river water and rice. These 20 isolates did not possess iaaM, iaaH, or etz genes. Group II, consisting of 34 melon isolates, harbored iaaM,
iaaH and etz genes, but did not cause either blight on welsh onion or HR-like reaction on tobacco. Group III strains did not have the
iaaM, iaaH, and etz genes, nor did they cause any reaction on welsh onion or tobacco. The 42 strains in group III were isolated from bamboo grass,
Chinese silver grass, citrus, dogwood, melon, mugwort, silk tree, sweet corn, tea and welsh onion. Representative strains
of the three groups were tested for pathogenicity on melon and rice. Group Ι strains caused palea browning on rice but not
internal fruit rot on melon. On the contrary, group II strains did not cause disease on rice but caused internal fruit rot
on melon. Group III strains were not pathogenic on rice or melon. These results suggested that the host range of P. ananatis may be predicted by the reactions of welsh onion and tobacco and detection of iaaM, iaaH and etz genes. These tools may serve as rapid tests to identify the pathogenicity groups of P. ananatis. 相似文献
82.
Methane (CH4 ) is the second most important greenhouse gas (GHG) and that emitted from enteric fermentation in livestock is the single largest source of emissions in Japan. Many factors influence ruminant CH4 production, including level of intake, type and quality of feeds and environmental temperature. The objectives of this review are to identify the factors affecting CH4 production in ruminants, to examine technologies for the mitigation of CH4 emissions from ruminants, and to identify areas requiring further research. The following equation for CH4 prediction was formulated using only dry matter intake (DMI) and has been adopted in Japan to estimate emissions from ruminant livestock for the National GHG Inventory Report: Y = −17.766 + 42.793X − 0.849X2 , where Y is CH4 production (L/day) and X is DMI (kg/day). Technologies for the mitigation of CH4 emissions from ruminants include increasing productivity by improving nutritional management, the manipulation of ruminal fermentation by changing feed composition, the addition of CH4 inhibitors, and defaunation. Considering the importance of ruminant livestock, it is essential to establish economically feasible ways of reducing ruminant CH4 production while improving productivity; it is therefore critical to conduct a full system analysis to select the best combination of approaches or new technologies to be applied under long-term field conditions. 相似文献
83.
Kazuo Yagi Kazuhiko Akimoto Norihiko Mimori Toshiro Miyake Masaki Kudo Kazutaka Arai Shigeru Ishii 《Pest management science》2000,56(1):65-73
A series of novel 3‐(2,4,6‐trisubstituted phenyl)uracil derivatives has been synthesised and assayed for insecticidal/acaricidal activity. The assay indicated certain requirements for optimal insecticidal activity, which can be summarised as follows: (a) the substituents on the phenyl ring should possess hydrophobicity and electron‐withdrawing properties, and the sum of their volumes determines the level of activity; (b) the substituent at the 6‐position on the uracil ring should also possess electron‐withdrawing properties and hydrophobicity, together with the correct volume; (c) the 1‐position on the uracil ring should be unsubstituted for activity against Nephotettix cincticeps and Epilachna vigintioctopunctata, but substituents with length C3 to C4 may be optimal for activity against Tetranychus urticae; (d) certain substituents at the 5‐position of the uracil ring give activity against E vigintioctopunctata and T urticae, but not against N cincticeps; (e) a thiocarbonyl group at the 2‐position of the uracil ring is less effective than a carbonyl group. Of the compounds assayed, 3‐(2,6‐dichloro‐4‐trifluoromethylphenyl)‐6‐trifluoromethyluracil showed high activity against all the species assayed. © 2000 Society of Chemical Industry 相似文献
84.
Yuji Ueda Masaki Ito Tsutomu Hattori Yoji Narimatsu Daiji Kitagawa 《Fisheries Science》2009,75(1):47-54
Terminal molting probability (TMP) of snow crab Chionoecetes opilio was estimated using instar- and state-structured model incorporating the terminal molt in the waters off the Pacific coast
of northern Honshu, Japan. TMP is defined as the probability that terminal molt occurs within a year in an instar and is an
important parameter for stock assessment. TMP was estimated from the model and the rate of terminal molted crabs (RTM) for
instars, which means carapace widths over 30 mm. Carapace widths at RTM of 0.5 were 81 mm for males and 66 mm for females.
TMP was estimated as 0.23 and 0.29 for these carapace widths, respectively. Carapace widths at TMP of 0.5 were 94 mm for males
and 71 mm for females, and for these carapace widths 57% of male and 50% of female crabs were considered as old-shell which
had survived 1 year or more from terminal molt. Changing the fishing or natural mortality by ±0.1, the maximum difference
of TMP was less than 0.1 from default estimates. 相似文献
85.
Washizu T Washizu M Zhang C Matsumoto I Sawamura M Suzuki T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2004,66(6):701-703
An 18 month-old, intact female American Shorthair cat was presented for evaluation of stunted growth and postprandial depression. Fasting serum ammonia and serum bile acid concentrations were above reference ranges at 396 microg/dl and 6.5 micromol/ l and their postprandial concentrations were 785 microg/dl and 9.5 micromol/l, respectively. The initial tentative diagnosis of a portosystemic shunt was excluded by mesenteric portography and histopathology of the liver. The cat was then suspected of a urea cycle enzyme deficiency and its urine was analyzed by gas chromatography-mass spectrometry. A presumptive diagnosis of ornithine transcarbamylase deficiency was made on the basis of the detection of orotic acid and uracil. 相似文献
86.
Karja NW Medvedev S Onishi A Fuchimoto D Iwamoto M Otoi T Nagai T 《The Journal of reproduction and development》2004,50(5):587-592
The effect of glucose supplementation at different times in in vitro culture on the developmental competence of in vitro produced (IVP) porcine embryos was examined. In Experiment 1, when IVP embryos were cultured in modified NCSU-37 supplemented with pyruvate and lactate (IVC-pyr/lac) for 0 h, 24 h, 48 h, 72 h, 96 h, or 118 h and subsequently in modified NCSU-37 supplemented with glucose (IVC-glu) until Day 6 (Day 0=day of in vitro fertilization), the rates of blastocyst formation were significantly higher in embryos cultured in IVC-pyr/lac for 24 or 48 h (24.4% and 23.0%, respectively) than in embryos cultured in IVC-pyr/lac for the whole culture period (14.5%). However, there were no significant differences between embryos obtained after the energy source replacement and embryos cultured in IVC-glu for the whole culture period on the rates (15.2%-24.4%, and 16.8% respectively). Replacement of pyruvate/lactate with glucose at 58 h of culture in Experiment 2 significantly enhanced the rate (31.3%) compared to those after replacement at 48 h, 53 h and 63 h of culture (20.6%, 20.8%, and 21.1%, respectively). In conclusion, replacement of pyruvate/lactate with glucose as the energy substrate was optimal at 58 h of culture for the development of porcine embryos to the blastocyst stage. 相似文献
87.
Nishii N Ohba Y Takasu M Katoh K Kitoh K Sasaki Y Kitagawa H 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2005,67(4):399-402
To elucidate the cause of growth retardation, 14 cattle with renal tubular dysplasia (RTD) were investigated by determining serum growth hormone (GH) and insulin-like growth factor (IGF)-1 concentrations. Compared with 6 healthy cattle, the baseline, maximum, area under the curve and peak amplitude of serum GH concentrations were higher or tended to be higher. Serum IGF-1 concentrations were lower normal or lower in cattle with RTD than in healthy cattle. Serum IGF-1 concentrations correlated significantly with body weight and chest girth, but not with serum GH and creatinine concentrations. Growth retardation in RTD might be associated partially with GH resistance. 相似文献
88.
Takasu M Yayota M Nakano M Nishii N Ohba Y Okada K Maeda S Miyazawa K Kitagawa H 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2005,67(12):1269-1271
To evaluate the nutriture of Japanese black cattle with growth retardation, a metabolic profile test was carried out in 8 cattle with growth retardation and in 10 cattle with normal growth. During our observation for 1 month before blood sampling, the cattle with growth retardation ingested their forage completely. They showed lower low-density lipoprotein and albumin concentrations, and higher urea nitrogen, actoacetic acid and beta-hydroxybutyric acid concentrations than the control. There were no significant differences in glucose, free fatty acid, total cholesterol, ammonia, inorganic phosphorus, and calcium concentrations between the cattle with growth retardation and the control. These data suggested that the cattle with growth retardation subjected to energy-negative condition in spite of their good forage intake. 相似文献
89.
Bergqvist AS Yokoo M Båge R Sato E Rodríguez-Martínez H 《The Journal of reproduction and development》2005,51(4):445-453
Hyaluronan is involved in fundamental reproductive events such as sperm storage in the female reproductive tract, fertilization, and early embryo development, these functions are presumably mediated by its major cell surface receptor, CD44. The present study was conducted to investigate the presence and localization of CD44 in the bovine oviductal epithelium, using immunohistochemical and Western blot methods on tissue sections and epithelial cell extracts collected from the uterotubal junction (UTJ), isthmus, and ampulla of animals in the oestrus or luteal phase of the oestrous cycle. While positive immunolabelling for CD44 was found on the ad-luminal surface and supra-nuclear region of epithelial cells in all tubal segments investigated, in the UTJ, there were epithelial cells in which the entire cytoplasm positively stained. We found no differences in terms of CD44-positive staining between the different stages of the oestrous cycle. Presence of CD44 was detected by Western blotting in the tubal epithelium as a single band at 200 kDa. Although it appeared in all tubal segments, the expression of CD44 protein was more accentuated in the sperm reservoir (UTJ) than in the other segments. This is the first time CD44 has been detected in the epithelium of the tubal sperm reservoir in cattle, suggesting a pathway for the action of hyaluronan in this segment. 相似文献
90.
Takasu M Hagiwara Y Ohba Y Nishii N Hosoda I Kitoh K Katoh K Kitagawa H 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2005,67(11):1149-1153
Endocrine patterns were compared in 2 strains of Japanese black cattle with growth retardation; MHO- and HSK-paternal strains (MHO and HSK cattle, respectively). MHO cattle (n=8) displayed lower serum concentrations of insulin-like growth factor-1 (IGF-1), triiodothyronine (T3), thyroxine (T4), and cortisol (31.1+/-20.7 ng/ml, 73.9+/-51.9 ng/dl, and 2.9+/-2.9 microg/dl, 1.3+/-0.7 microg/dl, respectively) than those in both HSK cattle (n=5) (64.9+/-47.6 ng/ml, 97.8+/-40.7 ng/dl, 4.1+/-2.1 microg/dl and 1.8+/-1.1 microg/dl, respectively), and the controls (n=6) (314.7+/-197.2 ng/ml, 140.2+/-21.3 ng/dl, 5.8+/-1.7 microg/dl, and 3.0+/-1.4 microg/dl, respectively). The area under the concentration curve of growth hormone (GH-AUC 0-600 min) in MHO cattle (22210+/-18951 ng.min/ml) tended to be greater than those in HSK (7887+/-6340 ng.min/ml) and the controls (2811+/-1275 ng.min/ml). MHO cattle showed a high GH-AUC0-600 min in contrast to a low serum IGF-1 concentration, as well as lower serum T3, T4, and cortisol concentrations. HSK cattle exhibited the same secretory patterns, but much more moderately. Growth retardation in Japanese black cattle exhibits some variations based on pedigree. 相似文献