排序方式： 共有20条查询结果，搜索用时 203 毫秒
1.
2.
3.
Real‐time polymerase chain reaction (PCR) assays for 11 representative rumen bacterial species were validated. The sensitivity was tested by using the serially diluted target 16S rDNA from respective bacterial species. The recovery of the target DNA and the assay reproducibility were determined using DNA from rumen fluid spiked with different quantities of the target. Minimum detection levels for the target were 10–100 copies in pure culture. The recovery of the added target ranged from 82.4 to 116.6%. The intra‐ and inter‐assay variations of each assay were <9.4 and <12.6%, respectively. Therefore, the real‐time PCR assays evaluated in the present study are considered to be sufficiently reliable for monitoring all 11 bacterial species in the rumen. The assays were then applied to the monitoring of the bacterial species attached to ruminally incubated rice straw. Among the monitored fibrolytic species, Fibrobacter succinogenes was found to be the most dominant, accounting for 2.61% of total bacteria after 24 h incubation. Selenomonas ruminantium and Streptococcus bovis, non‐fibrolytics, were detected on the rice straw at 8.96% and 1.16% of total bacteria, respectively. Such high levels of non‐fibrolytics on the plant fiber suggest a synergistic relationship between fibrolytics and non‐fibrolytics. 相似文献
4.
依据林下多年生草本植物山酢浆草Oxalis griffithii的形态学特征,将其生活史划分为4个阶段,并根据3种生境下山酢浆草种群的野外调查资料建立了不同种群的Lefkovitch结构矩阵模型,在此基础上预测了山酢浆草种群的动态及其阶段结构的变化;同时,运用敏感度、贡献率指标分析了影响种群动态的关键生活史阶段。结果表明：不同生境下山酢浆草种群的动态发展趋势不尽相同,常绿阔叶林下的种群（MD）呈稳定发展状态,其他2种生境下种群表现出衰退的发展趋势;种群的动态变化过程受个体的生长、残存、萎缩和繁殖等的综合影响;不同生活史阶段对种群动态的影响差异显著,种群动态过程及其发展趋势主要受种群内较大阶段个体的影响。图2表5参19 相似文献
5.
Weak activity of UDP-glucuronosyltransferase toward Bisphenol analogs in
mouse perinatal development
Risa YABUSAKI Hidetomo IWANO Sumito TSUSHIMA Nanako KOIKE Naoko OHTANI Kentaro TANEMURA Hiroki INOUE Hiroshi YOKOTA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(11):1479-1484
Bisphenol A (BPA) is a widely used industrial chemical that disrupts endocrine function.
BPA is an endocrine disrupting chemical (EDC) that has been demonstrated to affect
reproductive organ development, brain development, metabolic disease and post-natal
behavior. Accordingly, Bisphenol analogs, Bisphenol F (BPF, bis (4-hydroxyphenyl) methane)
and Bisphenol AF (BPAF, 4,4-hexafluoroisopropylidene) diphenol) are used as replacements
for BPA. BPA is mainly metabolized by UDP-glucuronosyltransferase (UGT), UGT2B1, but this
effective metabolizing system is weak in the fetus. In the present study, we demonstrated
that hepatic UGT activity toward BPAF was very weak, in comparison with BPA and BPF, in
the fetus, pups and dams. Conversely, hepatic UGT activity toward BPF was very weak in the
fetus and newborn pups, and was increased to the same level as BPA post-partum. In
conclusion, BPAF possibly tends to accumulate in the fetus, because of weak metabolism
during the perinatal period, suggesting that the metabolism of individual Bisphenol
analogs requires assessment to properly gauge their risks. 相似文献
6.
Hidehisa YAMANO Satoshi KOIKE Yasuo KOBAYASHI Hiroshi HATA 《Animal Science Journal》2008,79(2):234-242
The analysis of 16S rDNA sequence of bacteria in feces of Hokkaido native horses and light horses were performed to compare the hindgut microbiota between the two breeds. One hundred and four bacterial 16S rDNA clones (57 clones from four native horses and 47 clones from two light horses) were obtained. Only four sequences (3.8% of total sequences) showed 97% or more similarity to known species. The sequences were mainly affiliated with Cytophaga–Flavobacter–Bacteroides and low GC Gram‐positive bacteria (LGCGP). Proportion of LGCGP was higher in light horses. Other phyla including Verrucomicrobia, Spirochaetes and Archaea were detected only for native horses, suggesting high diversity of microbiota in native horses. In LGCGP, clusters related to known cellulolytic species were found only for native horses, while a cluster related to soluble sugar‐utilizing species was detected only for light horses. The library composition‐comparing software LIBSHUFF showed significant (P < 0.05) difference of fecal microbiota between the horse breeds. The number of Fibrobacter succinogenes‐related sequence and the frequency of detection of novel groups were found to be higher in native horses by selective amplification analysis. The results suggest that genetic diversity and population size of the F. succinogenes group are higher in the hindgut of native horses. 相似文献
7.
Ryosuke FUMA Shinya OYAIZU Yoko NUKUI Satoshi KOIKE Yasuo KOBAYASHI 《Animal Science Journal》2012,83(10):696-703
A series of in sacco and in vitro studies were carried out to evaluate bean husks for activation of fibrolytic rumen bacteria and rice straw digestion. First, lablab bean husk, chickpea husk and rice straw were suspended in the rumen of sheep to analyze the bacterial consortium developed on each fiber source. Known members of fiber‐associating bacteria were found on both lablab bean husk and rice straw, but some of these bacteria were lacking on chickpea husk. Second, a pure culture study was carried out using six strains of Fibrobacter succinogenes. Both husks stimulated the growth of all tested strains, including a strain that did not grow on rice straw. The strain OS128 that showed the highest growth on rice straw displayed even higher growth on lablab bean husk without a time lag. Finally, two‐step incubations were carried out to determine whether prior incubation of rumen fluid with husks stimulates subsequent rice straw digestion. Higher digestibility of rice straw was recorded in the second‐round incubation following the first incubation with bean husks. These results suggest that the tested bean husks improve the digestion of rice straw by activating fibrolytic F. succinogenes and other associated bacteria. 相似文献
8.
It is concluded that mitochondria are involved in three steps of porphyrin and heme biosynthesis-first, in the formation of delta-aminolevulinic acid from glycine and active succinate; second, in the synthesis of protoporphyrin; third, in the incorporation of iron into the porphyrin ring-that is, in heme formation. 相似文献
9.
10.