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11.
Abe Y Lee DS Sano H Akiyama K Yanagimoto-Ueta Y Asano T Suwa Y Suzuki H 《The Journal of reproduction and development》2008,54(4):290-294
Due to the recent outbreak of avian influenza, transportation of frozen canine semen with egg yolk has been sharply restricted. Thus, there is urgent need to develop a novel egg yolk-free extender for freezing canine spermatozoa. In the present study, the effect of using skim milk/glucose (SG)-based extender without egg yolk on the motility and fertilizing capacity of canine spermatozoa frozen-thawed in the presence of glycerol was examined. There was a tendency for the proportion of motile spermatozoa exposed to SG-based extender for 3 h to be higher than that exposed for 1 h, but the difference was not significant. The motility and other viability parameters of canine spermatozoa after thawing were similar to those obtained with an egg yolk-based extender. When spermatozoa frozen with SG-based extender containing glycerol after 3 h exposure were transcervically inseminated into 2 recipient bitches, a total of 6 pups were obtained. These results suggest that a simple extender composed of skim milk, glucose and glycerol is useful for cryopreservation of canine spermatozoa, which may contribute to improved exchange of genetic material and efficient production of companion and working dogs, such as guide dogs for the blind. 相似文献
12.
Seki Y Seimiya YM Motokawa M Yaegashi G Nagai M Hayashi M 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2008,70(4):393-395
The E2 regions of 177 bovine viral diarrhea virus (BVDV) strains isolated in Japan between 1957 and 2006 were analyzed for genotyping. The strains were classified into 8 genotypes (1a, 1b, 1c, 1d, 1e, 1f, So and 2a) based on the phylogenetic analysis. The restriction fragment length polymorphism (RFLP) analysis of the RT-PCR products using 6 selected enzymes (Apo I, Mly I, BstAP I, Pvu II, Ear I, EcoR V) disclosed the cutting patterns classified into 11 groups (I-XI), each of that consisted of strains belonging to a single genotype. Namely, groups-I and -II were composed by genotype-1a strains, groups-III and -IV by 1b strains, and groups-V and -VI by 1c strains. Other groups-VII, -VIII, -IX, -X and -XI comprised genotypes-1d, -1e, -1f, -So and -2a strains, respectively. The results suggest that the RFLP analysis can simply and rapidly differentiate the 8 genotypes of BVDV strains. 相似文献
13.
Seki Y Seimiya YM Yaegashi G Kumagai S Sentsui H Nishimori T Ishihara R 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2004,66(12):1503-1508
During the period from 2001 to the following year, progenital diseases had been epidemic among the draft stallions and mares pastured together in Iwate Prefecture, the northeastern district of Japan. A stallion and 8 of 31 mares were affected in 2001, and 1 of 2 stallions and 10 of 36 mares in 2002. The clinical symptoms consisted of the formation of papules, pustules, ulcers and scabs on the progenital skin and mucosa in stallions and mares. In 2002, Equine herpesvirus 3 (EHV3) was isolated from 2 mares and the glycoprotein G gene of the virus detected from a stallion and 4 mares by polymerase chain reaction. Serum neutralizing tests showed that 12 of 38 horses, 10 clinically and 2 subclinically affected, changed to be positive for the EHV3 antibody. The results suggest that the horses were affected with equine coital exanthema (ECE) through coitus. Five mares with the antibody at the pre-pastured period may have been the possible origins of EHV3 infection in 2002, although the exact origin in 2001 remains unknown. The artificial insemination was performed for the prevention of ECE spreading through coitus on the pasture in 2003. There was no epidemic of the disease in 31 mares, although 3 mares with the antibody at the pre-pastured period showed the significant increase in the titers during the pastured period. 相似文献
14.
Ishii N Nakahigashi K Baba T Robert M Soga T Kanai A Hirasawa T Naba M Hirai K Hoque A Ho PY Kakazu Y Sugawara K Igarashi S Harada S Masuda T Sugiyama N Togashi T Hasegawa M Takai Y Yugi K Arakawa K Iwata N Toya Y Nakayama Y Nishioka T Shimizu K Mori H Tomita M 《Science (New York, N.Y.)》2007,316(5824):593-597
Analysis of cellular components at multiple levels of biological information can provide valuable functional insights. We performed multiple high-throughput measurements to study the response of Escherichia coli cells to genetic and environmental perturbations. Analysis of metabolic enzyme gene disruptants revealed unexpectedly small changes in messenger RNA and proteins for most disruptants. Overall, metabolite levels were also stable, reflecting the rerouting of fluxes in the metabolic network. In contrast, E. coli actively regulated enzyme levels to maintain a stable metabolic state in response to changes in growth rate. E. coli thus seems to use complementary strategies that result in a metabolic network robust against perturbations. 相似文献
15.
We investigated the denitrification activity and the distribution of the denitrifying bacteria of a boring survey site located on a volcanic plateau, where the geological profiles from surface to deep subsurface soil at the groundwater level had been examined. There were differences between the water quality in the Ito pyroclastic flow deposit (Shirasu) layer (44.2 to 54.5 m) and that in the Osumi pumice fall deposit (Pumice) layer (below 54.5 m) corresponding to the impermeable layer of unconfirmed groundwater: The nitrate concentration was less than 1 mg kg−1 in the Shirasu layer and more than 10 mg kg−1 in the Pumice layer (Kubota et al. 2005). Denitrification activity decreased from the surface to the loam layer and was enhanced in the Shirasu layer and the Haraigawa clay impermeable layer at a depth of 65 m. It was observed that the highest potential denitrification activity (103 ng-N2 O d−1 g−1 ) in the impermeable layer was almost equal to that of a Kuroboku surface soil with slurry application. Viable counts of the sonic-samples, which indicated the presence of bacterial group with soil particles attached, increased in the impermeable layer. The ratios of viable or denitrifying bacterial counts in the sonic-samples to those in the wash-samples were significantly higher in the impermeable layer than those in the surface layer. These results suggest that the hydrogeological conditions enhanced the denitrification activity in the impermeable layer, the niches of which might be relatively anaerobic and have a sufficient supply of substrates to enable the denitrifying bacterial populations to multiply. 相似文献
16.
Partial sterilization causes a change in N mineralization in soil. An increase in the net rate of N mineralization was reported in soil with chloropicrin applied to it (Rovira 1976), and has been well known in soil fumigated with chloroform to measure the microbial biomass N (Jenkinson and Ladd 1981). The gross rate of N mineralization increased in soil inoculated with fresh soil following fumigation with chloroform (Shen et al. 1984). The increased rate of N mineralization has been attributed to the rapid decomposition of organisms killed by partial sterilization (Jenkinson 1966). On the other hand, Nira et al. (1996) reported that the application of a fumigant in a field depressed the gross rates of N mineralization and immobilization in spite of the increase in the net rate of N mineralization. These results suggested that the increase in the net rate of N mineralization by partial sterilization is presumably due to the change in the ratio of N mineralization to immobilization. However, the residues of a fumigant may depress gross N transformation in the field, because the residues may continue to influence microbial activity long after the original treatment (Jenkinson 1966). Some effects of partial sterilization without residues on gross N mineralization remain to be determined. 相似文献
17.
Infection with Perkinsus species, primarily P. olseni, is thought to be a major cause of the decline of Manila clam populations in Japan since the 1980s. However, the pathogenicity of the infection has not been sufficiently evaluated to estimate the impact of infection on wild Manila clam populations. We experimentally challenged juvenile (3- to 6-mm shell length) and adult (18- to 22-mm shell length) Manila clams with P. olseni at 18, 23, 28, and 30 °C. Mortality was significantly higher in challenged groups than in control groups. The difference in mean mortality between the challenged and control groups (all life stages and temperatures) was only significant above a threshold of infection intensity ~106 cells/g soft wet tissue (SWT). As temperature increased, the onset of mortality occurred more rapidly. The increase in mortality occurred earlier in juveniles than adults at 28 °C and lower. Our results suggest that the pathogenicity of P. olseni is higher in juveniles than in adults and at higher water temperatures. Given the infection intensities (ca. 106 cells/g SWT) previously reported in wild Manila clams, the parasite likely has considerable impact on wild Manila clam populations, particularly juveniles during periods of high temperature. 相似文献
18.
Hiroki Noda Noriko Yamagishi Hajime Yaegashi Fei Xing Jipeng Xie Shifang Li Tao Zhou Tsutae Ito Nobuyuki Yoshikawa 《Journal of General Plant Pathology》2017,83(2):83-90
The causal agent of apple mosaic disease has been previously thought to be solely caused by apple mosaic virus (ApMV). In this study, we report that a novel ilarvirus is also associated with apple mosaic disease. Next-generation sequencing analysis of an apple tree showing mosaic symptoms revealed that the tree was infected with three apple latent viruses (apple stem pitting virus, apple stem grooving virus, and apple chlorotic leaf spot virus) and a novel ilarvirus (given the name apple necrotic mosaic virus (ApNMV)) that is closely related to Prunus necrotic ringspot virus (PNRSV) and ApMV. The genome of ApNMV consists of RNA1 (3378 nt), RNA2 (2767 nt), and RNA3 (1956 nt). A phylogenetic analysis based on the coat protein amino acid sequences indicated that the novel virus belongs to the same subgroup 3 of the genus Ilarvirus as PNRSV and ApMV. The presence of mosaic leaves, which tend to be unevenly distributed in diseased apple trees, was correlated with the internal distribution of ApNMV. RT-PCR detection of mosaic-diseased apple trees in Japan indicated that ApNMV was detected in apple trees introduced from China, whereas ApMV was detected from cultivated apple trees in domestic orchards. Consistent with these findings, a survey of mosaic-diseased apple trees in major apple-producing provinces in China revealed that the majority of apple trees showing mosaic symptoms in China are infected with ApNMV. 相似文献
19.
Tomoyoshi Yoshinaga Nobuyuki Tsutsumi Kathryn Ann Hall Kazuo Ogawa 《Fisheries Science》2009,75(5):1167-1176
In the mid-1990s, Neoheterobothrium hirame suddenly appeared as a new species in olive flounder Paralichthys olivaceus in Japanese coastal waters. Anemia caused by the parasite has prevailed in wild and cultured populations of olive flounder since that time. In this study, to clarify the origin of N. hirame, two Neoheterobothrium species, namely unidentified Neoheterobothrium species (tentatively abbreviated as Neoheterobothrium sp. PL) and N. affine, were collected from Paralichthys lethostigma and Paralichthys dentatus, respectively, off the east coast of North America and compared with N. hirame collected in Japan. No substantial differences were detected in the morphology and DNA sequences of ITS1-5.8S rRNA-ITS2 and mitochondrial cytochrome oxidase subunit I (mt COI) regions between N. hirame and Neoheterobothrium sp. PL. On the other hand, the congeneric N. affine was clearly distinguished from both N. hirame and Neoheterobothrium sp. PL in its longer isthmus and the DNA sequences in ITS1 and mt COI. The absence of differences between N. hirame and Neoheterobothrium sp. PL and the clear difference between both of these and N. affine indicate that N. hirame is conspecific with Neoheterobothrium sp. PL infecting P. lethostigma and that N. hirame was recently introduced from North America to Japan. 相似文献
20.
Sugimoto M Kaneko M Onuma H Sakaguchi Y Mori M Abe S Soga T Tomita M 《Journal of agricultural and food chemistry》2012,60(10):2586-2593
Japanese sake (rice wine) is commonly heat treated (pasteurized) to maintain its quality. In this study, temporal changes in the metabolite profiles of pasteurized and unpasteurized sake were investigated during storage. Metabolomic analyses were conducted for eight sets of pasteurized and unpasteurized sake obtained from single process batches stored at 8 or 20 °C for 0, 1, 2, or 4 months. Capillary electrophoresis time-of-flight mass spectrometry and liquid chromatography tandem mass spectrometry were used to obtain charged metabolite and sugar profiles, respectively. The total amino acid concentration decreased with storage, and the decrease was faster in pasteurized sake than in unpasteurized. The organic acid concentrations were relatively constant in both types of sake. Peptide and glucose concentrations increased and polysaccharide concentrations decreased in unpasteurized sake, while they were relatively constant in pasteurized sake. Rather than stabilizing the sake metabolite profile during storage, pasteurization results in characteristic changes compared to unpasteurized sake. 相似文献