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Controlling established horsenettle plants is achieved by suppressing shoot emergence from root systems. The seasonal pattern of shoot emergence and its possible endogenous control in horsenettle ( Solanum carolinense L.) were investigated. The shoot emergence period in an undisturbed population was limited to a seven-week period from mid-April, and a little longer in tilled conditions. Detached roots showed very high shoot-sprouting ability under 15–30°C throughout the year. In shoot clipping experiments, new shoots sprouted only from the stem and not from the root when attached to shoots, whether above-ground or underground. On the contrary, new shoots sprouted from the roots when all parts of the shoots were clipped off. From these results, the limited shoot emergence period in horsenettle is thought to be initiated by temperatures necessary for sprouting and is ended by a growth correlation effect between early emerged and matured shoots. 相似文献
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Atsushi KIMURA Yo-Han KIM Kazuyoshi HASHIZUME Akira ITO Katsuyuki MUKAI Keiichiro KIZAKI Shigeru SATO 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(5):829
We investigated the effect of oral administration of β-cryptoxanthin (β-CRX) on its serum concentration and peripheral neutrophil functions by the chemiluminescence (CL) response in Holstein cattle. A single oral administration of β-CRX was performed for serum β-CRX concentration (0, 0.05, 0.1, or 0.2 mg/kg body weight [BW]) and for peak CL response of peripheral neutrophils (0.2 mg/kg BW). The serum β-CRX concentration was peaked on 2 days after, similar to peak CL response on 3 days after β-CRX administration. Therefore, a single oral administration of β-CRX (0.2 mg/kg BW) induces higher serum concentration and concurrently enhances bactericidal ability of peripheral neutrophils in Holstein cattle. 相似文献
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调查了曾经暴发沙门氏菌病的四个猪场的14头病猪,发现在这些猪的肿胀淋巴结中出现带有淋巴细胞排空的肉芽肿性炎症。应用免疫标记和PCR方法在病变部位检测到猪圆环病毒2(PCV2)抗原和PCV2DNA。此外,在这些病猪的肺脏中检测出猪繁殖与呼吸综合征病毒(PRRSV),分离到猪霍乱沙门氏菌。在9头沙门氏菌感染猪中,有5头为沙门氏菌、PMWS与PRRSV并发感染,其数量(55.6%)远远高于沙门氏菌与PMWS感染猪(22.2%)或沙门氏菌与PRRSV感染猪(22.2%)。 相似文献
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Haruka KATAOKA Nanami KOITA Natsuko ITO KONDO Hiroshi C. ITO Momoko NAKAJIMA Kunikazu MOMOSE Hiroko IIMA Tomoo YOSHINO Tomoko AMANO Takio KITAZAWA Daiji ENDOH Nobuyoshi NAKAJIMA Hiroki TERAOKA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2022,84(3):358
The red-crowned crane Grus japonensis in Hokkaido, Japan forms a closed population as a residence that is independent of the mainland population. Based on observations of a limited number of individuals as well as cranes in captivity, red-crowned cranes are omnivores and eat fish, worms, insects and plants in their own territories except in winter, when they are fed with dent corn that is supplied in eastern Hokkaido. DNA metabarcoding based on high throughput sequencing was carried out using universal primer sets for cytochrome oxidase subunit I gene. Feces from 27 chicks collected in June and July in the period from 2016 to 2018 and intestinal contents from 33 adult and subadult cranes that were found dead almost throughout year in 2006–2013 in the field in eastern Hokkaido were used. Although compositions varied considerably in the cranes, both insects and fish were found in adults and subadults to the same extents, while insects were predominant in chicks. Both insects and fish were detected in all seasons for adults and subadults. Horse flies, scarab beetles and weevils accounted for the most of the insects regardless of the life stage. Dace, stickleback, flatfish and sculpin were the major fish species in adults, while chicks ate almost only stickleback. The results provide the first comprehensive data on carnivorous diets in wild red-crowned cranes in eastern Hokkaido as basis for conservation of red-crowned cranes, for which the life style and area continue to change. 相似文献
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Chiharu HIDAKA Kosuke SODA Toshihiro ITO Hiroshi ITO 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2022,84(1):121
Although verogenic Newcastle disease viruses (NDVs) generally cause subclinical infection in waterfowls such as ducks, NDVs with high virulence in waterfowl have been sporadically reported. We previously reported that the NDV d5a20b strain, which is obtained by serial passaging of the velogenic 9a5b strain in domestic ducks, showed increased virulence in ducks (Hidaka et al., 2021). The d5a20b strain had 11 amino acid substitutions in its P/V, M, F, HN, and L proteins as compared to 9a5b. In the present study, we generated a series of recombinant (r) NDVs with these amino acid substitutions to identify the molecular basis of virulence of NDV in ducks, and evaluated their influences on virulence and in vitro viral properties. Each of the single amino acid substitutions in either the F protein I142M or the M protein Q44R contributed to the enhancement of intracerebral and intranasal pathogenicity in domestic ducks. The cell-cell fusion activity of the virus with F I142M was five times higher than that of the parental r9a5b. The virus with M Q44R rapidly replicated in duck embryo fibroblasts. Additionally, the rM+F+HN strain, which has the same amino acid sequences as d5a20b in M, F, and HN proteins, showed the highest level of virulence and replication efficiency among the generated recombinant viruses, nearly comparable to rd5a20b. These results suggest that multiple factors are involved in the high growth ability of NDV in duck cells, leading to increased virulence in vivo. 相似文献
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Hiroya ITO 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(5):583-586
The genetic organization of the gene involved in the capsular polysaccharide
(CPS) biosynthesis of Actinobacillus pleuropneumoniae serotype 14 has
been determined. The DNA region for the CPS biosynthesis of serotype 14
(cps14) comprised 9 open reading frames, designated as
cps14AB1B2B3CDEFG genes, encoding
Cps14A to Cps14G protein, respectively. Cps14A was similar to CpsA of A.
pleuropneumoniae serotypes 1, 4 and 12; the Cps14B1 and
Cps14B2 were similar to CpsB of A. pleuropneumoniae
serotypes 1, 4 and 12, suggesting that CPS structure of A.
pleuropneumoniae serotype 14 would belong to Group I including A.
pleuropneumoniae serotypes 1, 4, 12 and 15. Surprisingly, the overall
nucleotide sequence, deduced amino acid sequence, and the genetic organization of the
cps14 were nearly identical to those of Actinobacillus
suis. This study will provide the molecular basic knowledge for development of
diagnostics and vaccine of A. pleuropneumoniae serotype 14. 相似文献
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Reduction of transport stress of ayu by obligated schooling 总被引：3，自引：0，他引：3
KEI'ICHIRO IGUCHI FUMINARI ITO KOGI OGAWA NAOTO MATSUBARA TAIGA YODO TSUGIKO YAMASAKI 《Fisheries Science》2002,68(4):849-853
We investigated stress responses of ayu Plecoglossus altivelis under the hypothesis that overcrowding during transport can be a stressor and the stress predisposes fish to disease by decline in immunocompetence. The extent of stress response was determined under different fish densities. As inferred from the serum concentration of cortisol 1 day after the treatment, the density at more than 23 kg/m3 , which was within the range of normal transporting procedures, acutely evoked intense stress responses. To examine a possible way to reduce the stress response of fish under crowding conditions, we compared two fish groups established in water tanks with circulating (whirling) and turbulent currents at the same density. The cortisol levels 1 day after the treatment were 2.5-fold higher in turbulent current than in whirling current. Fish in whirling current formed a school, while those in turbulent current aggregated with each other. Schooling of fish induced by water flow may reduce their stress responses during transport. A transport system with a directional water flow should keep fish in good condition without reducing the number of fish contained. 相似文献