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301.
Tsuyoshi SHIMMURA Satoshi HIRAHARA Yusuke EGUCHI Katsuji UETAKE Toshio TANAKA 《Animal Science Journal》2007,78(3):314-322
The aim of the present study was to compare old layers' level of welfare and performance between conventional and large furnished cages under hot environmental conditions. At the age of 80 weeks, 104 Boris Brown layers were divided into two groups: 12 conventional cages (two hens/cage) and four large furnished cages (20 hens/cage, 240 cm wide × 62 cm deep). The room temperature was set to fluctuate between 25 and 33°C in a day. The hens' behavior, immune response, performance and physical condition were measured. Aggression and moving were more frequent in furnished than in conventional cages (P < 0.05 for both items). Egg production (P < 0.05), egg mass (P < 0.05) and feed conversion ratio (P < 0.01) were better in conventional cages than in furnished cages. No significant differences were found in the birds' immune responses or physical condition between the cage designs. In conclusion, under a hot environment, the performance of old layers in large furnished cages was lower compared with that in small conventional cages, which might be due to their greater aggressive interactions. However, it was not evident that welfare level was lower in large furnished cages compared with conventional cages. Hereafter, additional studies about large furnished cages using young layers over a long term should be performed. 相似文献
302.
We screened for Japanese Black and Holstein bull sire samples to detect single nucleotide polymorphisms (SNPs) involving animo‐acid substitutions in the bovine prion gene in the entire coding region of the PRNP gene. Although three silent SNPs were found, we could not detect any SNP with animo‐acid substitution. We also examined the polymorphism of the octapeptide repeat number in these samples. There was no homozygous bull with repeat number 5. The frequency of heterozygous (6/5) bulls was 8% in the Japanese Black bull and 4% in the Holstein bull, respectively. The bull samples used in this study contain popular elite sires, so it appears that the polymorphisms of prion protein (PrP) are rather difficult to find in these two breeds in Japan, except for polymorphism of the octapeptide repeat number. 相似文献
303.
Takakuwa H Yamashiro T Le MQ Phuong LS Ozaki H Tsunekuni R Usui T Ito H Morimatsu M Tomioka Y Yamaguchi T Ito T Murase T Ono E Otsuki K 《Preventive veterinary medicine》2012,103(2-3):192-200
Repeated epizootics of highly pathogenic avian influenza (HPAI) virus subtype H5N1 were reported from 2003 to 2005 among poultry in Vietnam. More than 200 million birds were killed to control the spread of the disease. Human cases of H5N1 infection have been sporadically reported in an area where repeated H5N1 outbreaks among birds had occurred. Subtype H5N1 strains are established as endemic among poultry in Vietnam, however, insights into how avian influenza viruses including the H5N1 subtype are maintained in endemic areas is not clear. In order to determine the prevalence of different avian influenza viruses (AIVs), including H5N1 circulating among poultry in northern Vietnam, surveillance was conducted during the years 2006-2009. A subtype H5N1 strain was isolated from an apparently healthy duck reared on a farm in northern Vietnam in 2008 and was identified as an HPAI. Although only one H5N1 virus was isolated, it supports the view that healthy domestic ducks play a pivotal role in maintaining and transmitting H5N1 viruses which cause disease outbreaks in northern Vietnam. In addition, a total of 26 AIVs with low pathogenicity were isolated from poultry and phylogenetic analysis of all the eight gene segments revealed their diverse genetical backgrounds, implying that reassortments have occurred frequently among strains in northern Vietnam. It is, therefore, important to monitor the prevalence of influenza viruses among healthy poultry between epidemics in an area where AIVs are endemic. 相似文献
304.
Tsuyoshi Yamada Chisato Takenaka Shuichiro Yoshinaga Keizo Hirai 《Journal of Forest Research》2013,18(6):466-474
There is insufficient direct evidence of long-term changes in the chemical properties of forest soils to provide information for forestry management plans for sustainable site productivity. To understand changes in the chemical properties of forest soils in a specific high-precipitation climate in Japan, we re-investigated, in 1997, soil pits within a Japanese cedar (Cryptomeria japonica) forest in the Yanase region of Kochi Prefecture which had previously been surveyed in 1976. Comparison of the 1976 and 1997 results revealed significantly lower pH of surface and subsurface soils, and fewer exchangeable cations over time. In contrast, subsoil pH, concentrations of total carbon and nitrogen, and cation-exchange capacity (CEC) had not changed over the 21-year period. Estimation of proton and cation budgets in the forest ecosystem over 21 years, using data for the amounts in soil, biomass accumulation, and input through precipitation, revealed that biomass accumulation did not explain the cation depletion in soils. This suggests that cations were leached from the ecosystem. In contrast with previous reports, which showed Ca accumulation in Japanese cedar forest soils, our results indicated that high precipitation of more than 4,000 mm combined with acid deposition resulted in soil acidification and leaching of cations from soils, following the decrease in base saturation. 相似文献
305.
306.
Cloning of kuruma prawn Marsupenaeus japonicus crustin-like peptide cDNA and analysis of its expression 总被引:1,自引:0,他引:1
Achara RATTANACHAI Ikuo HIRONO Tsuyoshi OHIRA Yukinori TAKAHASHI Takashi AOKI 《Fisheries Science》2004,70(5):765-771
ABSTRACT: Antimicrobial peptides serve as an important component of the innate immune system of all species by functioning to provide a rapid first line defense against infection. Arthropod antimicrobial peptides have been well described in insects, whereas only a few molecules have been identified in crustaceans. Five variants (types 1–5) of Marsupenaeus japonicus crustin-like peptide cDNA that were obtained from a hemocyte cDNA library and polymerase chain reaction (PCR) amplification are reported here. Marsupenaeus japonicus crustin-like peptide type 1, the predominant type, has a cDNA consisting of 679 nucleotides and an open reading frame consisting of 573 base pairs coding for 191 amino acid residues. Other types contain varying glycine-rich repeats at the N-terminal amino acid sequences. The deduced amino acid sequences of these variants are highly similar to those of Litopenaeus setiferus (80% identity), Litopenaeus vannamei (80% identity) and Carcinus maenas crustins (44% identity). Expression of Marsupenaeus japonicus crustin-like peptide mRNA was detected in hemocytes, but not in the heart, hepatopancreas, gill, fore-gut, mid-gut, muscle, subcuticular epithelium or ovary. The expression level of crustin-like peptide mRNA increased significantly 1, 3 and 7 days post-peptidoglycan feeding as determined by quantitative real-time PCR. These results suggest that crustin-like peptide could have an important role in shrimp defense mechanisms. 相似文献
307.
Sho Kakizawa Toyoji Kaneko Tsuyoshi Ogasawara Tetsuya Hirano 《Fish physiology and biochemistry》1995,14(2):93-101
Plasma somatolactin (SL) concentrations were examined in chum salmon in relation to gonadal maturation; immature salmon in the Bering Sea at various stages of maturation, and mature salmon during upstream migration caught at the ocean, bay and river. Plasma SL concentrations as well as plasma prolactin (PRL) and growth hormone (GH) levels in the immature fish caught in the Bering Sea were maintained essentially at similar levels. Plasma SL in mature salmon increased significantly from the fish in the ocean to the fish in the river in both sexes. Although all the fish had fully developed gonads, females completed ovulation while still in the bay, whereas final spermeation in males was achieved after entry into the river. Thus, no clear correlation was seen between plasma SL levels and final gonadal maturation. On the other hand, plasma PRL concentrations in both male and female fish were higher in the fish in the river than those in the ocean and bay, and plasma GH levels were higher in both sexes in the fish in the bay and river than those in the ocean. Plasma levels of triglycerides, glucose, free fatty acids and ionized sodium and calcium were also examined. Significant-negative correlations were seen between plasma SL and plasma ionized calcium in mature male salmon, and between plasma SL and plasma triglycerides in mature female salmon. Although our findings do not rule out the possibility of the involvement of SL in final maturation, the results indicate that SL seems to be involved at least in energy and/or calcium metabolism during the spawning migration. 相似文献
308.
Hiroshi Hoshino Takeomi Isono Takuma Takayama Tsuyoshi Ishinazaka Akihiko Wada Yasunori Sakurai 《Fisheries Science》2006,72(5):922-931
Aerial and land-based sighting surveys were conducted to clarify the distribution of Steller sea lions during winter in the
northern Sea of Japan, along the west coast of Hokkaido, from 2001 to 2003. Aerial surveys revealed that sea lions gathered
around the Rishiri-Rebun Islands in March 2002 and 2003, and between Iwanai and Cape Obana in February 2003. Higher numbers
of sea lions were also confirmed at Cape Ofuyu and Cape Kamui on the central-west coast compared to that at the haul-out sites
in the 1980s on the upper-west coast in March 2002 and 2003. Additionally, fisherman observed sea lions along the coast of
the Tsugaru Strait from February to May 2003, where the presence of sea lions was not reported in the 1980s. These facts suggest
that sea lions have recently expanded their distribution southward. Land-based surveys at the recent haul-out sites indicated
that sea lions in the central-west coast were composed mainly of adult and subadult males (average: Cape Ofuyu 75.2%, Cape
Kamui 69.5%), which stayed from November 2002 to May 2003. In this area, sea lions arrived earlier and stayed longer than
in the 1980s. 相似文献
309.
Banks JA Nishiyama T Hasebe M Bowman JL Gribskov M dePamphilis C Albert VA Aono N Aoyama T Ambrose BA Ashton NW Axtell MJ Barker E Barker MS Bennetzen JL Bonawitz ND Chapple C Cheng C Correa LG Dacre M DeBarry J Dreyer I Elias M Engstrom EM Estelle M Feng L Finet C Floyd SK Frommer WB Fujita T Gramzow L Gutensohn M Harholt J Hattori M Heyl A Hirai T Hiwatashi Y Ishikawa M Iwata M Karol KG Koehler B Kolukisaoglu U Kubo M Kurata T Lalonde S Li K Li Y Litt A Lyons E Manning G Maruyama T Michael TP 《Science (New York, N.Y.)》2011,332(6032):960-963
310.
Fukata T Naito F Yoshida N Yamaguchi T Mizumura Y Hirai K 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2002,64(11):1079-1080
A total of 1,013 feces samples and 8 mesenteric lymphonodus samples obtained from apparently healthy dogs were examined for the incidence of salmonella infection. One strain of S. typhimurium (ST) was isolated from feces of one dog, and S. enteritidis (SE) was isolated from the mesenteric lymphonodus of one dog. Sera obtained from 330 apparently healthy dogs were examined for Salmonella antibodies using an ELISA with heated whole cells of SE and ST. Fifty-one of the 330 serum samples were considered to be positive for salmonella antibodies, including 12 which were SE-positive and 39 which were ST-positive. These results indicate that dogs cause possible environmental problems as Salmonella carriers. 相似文献