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231.
Michiko NAKAI Manabu OZAWA Naoki MAEDOMARI Junko NOGUCHI Hiroyuki KANEKO Junya ITO Akira ONISHI Naomi KASHIWAZAKI Kazuhiro KIKUCHI 《The Journal of reproduction and development》2014,60(3):256-259
In pigs, the embryonic developmental ability after intracytoplasmic sperm injection (ICSI) is inferior to that resulting from
in vitro fertilization (IVF). We evaluated the timing of cell division up to blastocyst formation on
embryonic development after ICSI using either whole sperm (w-ICSI) or the sperm head alone (h-ICSI) and IVF as a control. At
10 h after ICSI or IVF, we selected only zygotes, and each of the zygotes/embryos was evaluated for cleavage every 24 h until
168 h. We then observed a delay in the 1st and 2nd cleavages of h-ICSI embryos and also in blastocoele formation by w-ICSI
embryos in comparison with IVF embryos. The rate of blastocyst formation and the quality of blastocysts in both ICSI groups
were inferior to those in the IVF group. In conclusion, the delay in cleavage of porcine ICSI embryos shows poorer embryonic
development. 相似文献
232.
Takeshi Yamazaki Kenji Togashi Satoru Iwama Shigeo Matsumoto Kimihiro Moribe Takatoshi Nakanishi Koichi Hagiya Kiyoshi Hayasaka 《Animal Science Journal》2014,85(6):639-649
The effectiveness of the incorporation of genomic pre‐selection into dairy cattle progeny testing (GS‐PT) was compared with that of progeny testing (PT) where the fraction of dam to breed bull (DB) selected was 0.01. When the fraction of sires to breed bulls (SB) selected without being progeny tested to produce young bulls (YB) in the next generation was 0.2, the annual genetic gain from GS‐PT was 13% to 43% greater when h2 = 0.3 and 16% to 53% greater when h2 = 0.1 compared with that from PT. Given h2 = 0.3, a selection accuracy of 0.8 for both YB and DB, and selected fractions of 0.117 for YB and 0.04 for DB, GS‐PT produced 40% to 43% greater annual genetic gain than PT. Given h2 = 0.1, a selection accuracy of 0.6 for both YB and DB, and selected fractions of 0.117 for YB and 0.04 for DB, annual genetic gain from GS‐PT was 48% to 53% greater than that from PT. When h2 = 0.3, progeny testing capacity had little effect on annual genetic gain from GS‐PT. However, when h2 = 0.1, annual genetic gain from GS‐PT increased with increasing progeny testing capacity. 相似文献
233.
Hiromichi Ohtsuka Shigeo Fukuda Katsunori Kudo Michiko Tomioka Masateru Koiwa Kayoko Kimura 《Canadian journal of veterinary research》2013,77(3):226-230
Most of the metabolic diseases of dairy cows occur within the first 2 wk after calving, and cows with a metabolic disease are prone to infectious diseases. Although metabolic diseases are generally recognized as a risk factor for infectious diseases owing to the associated decrease in immune function, the difference in immune status between cows with milk fever (MF) or displaced abomasum (DA) during the lactation period has not been clarified. Therefore, the peripheral blood leukocyte populations in 38 multiparous Holstein cows from 1 herd were analyzed after calving. The cows were divided into 3 groups according to health: 21 cows that remained clinically healthy throughout the experimental period (control group), 9 cows that had MF on the day of calving, and 8 cows with an onset of DA within 4 wk after calving. The T- and B-cell numbers were lowest at week 0, and they increased gradually after calving. There was no significant difference between the 3 groups in the number of each subset of leukocytes on the day of calving, but the number of CD8+ T-cells was significantly lower in the MF and DA groups than in the control group at week 1. The numbers of CD4+, CD8+, and WC1+ T-cells tended to be lower in the DA group than in control group from weeks 4 to 12, a tendency not observed in the MF group. These data suggest that when cows have DA around the time of calving, their lymphocyte numbers remain lower until 12 wk after calving. 相似文献
234.
235.
Saito T Watanabe C Takemae N Chaisingh A Uchida Y Buranathai C Suzuki H Okamatsu M Imada T Parchariyanon S Traiwanatam N Yamaguchi S 《Veterinary microbiology》2009,133(1-2):65-74
Highly pathogenic avian influenza (HPAI) viruses of the H5N1 subtype have caused several rounds of outbreaks in Thailand. In this study, we used 3 HPAI viruses isolated in Thailand in January 2004 from chicken, quail, and duck for genetic and pathogenetic studies. Sequence analysis of the entire genomes of these isolates revealed that they were genetically similar to each other. Chickens, quails, domestic ducks, and cross-bred ducks were inoculated with these isolates to evaluate their pathogenicity to different host species. A/chicken/Yamaguchi/7/04 (H5N1), an HPAI virus isolated in Japan, was also used in the chicken and quail studies for comparison. All four isolates were shown to be highly pathogenic to chickens and quails, with 100% mortality by 10(6) EID50 inoculants of the viruses. They caused sudden death in chickens and quails within 2-4 days after inoculation. The mean death times (MDT) of quails infected with the Thai isolates were shorter than those of chickens infected with the same isolates. Mortality against domestic and cross-bred ducks ranged from 50 to 75% by intranasal inoculation with the 10(6) EID50 viruses. Neurological symptoms were observed in most of the inoculated domestic ducks and appeared less severe in the cross-bred ducks. The MDTs of the ducks infected with the Thai isolates were 4.8-6 days post-inoculation. Most of the surviving ducks infected with the Thai isolates had sero-converted until 14 dpi. Our study illustrated the pathobiology of the Thai isolates against different poultry species and would provide useful information for improving control strategies against HPAI. 相似文献
236.
Mitsuro KAMEYA-IWAKI Kimiaki MURAKAMI Shin-ichi ITO Kaoru HANADA Shuhei TANAKA 《Journal of General Plant Pathology》2000,66(1):64-67
Sequential transmission tests of Peanut stunt virus (PSV) and Cucumber mosaic virus (CMV) systemically infecting common bean, Phaseolus vulgaris, were conducted using Myzus persicae allowed to fast for 2 hr and then to acquisition feed on infected common bean plants or purified virus for 10 min. In the
sequential transmission tests using either one or 10 aphids per assay plant, three isolates of PSV (J,S,Y5) and one of CMV
(V) were transmitted from and to common bean up to a third or fourth inoculation access. Many aphids transmitted these viruses
to two or three plants. Purified viruses of PSV-S and CMV-V were also transmitted up to a third or second inoculation access
at low percentage. On tobacco, Nicotiana tabacum, aphids transmitted PSV-S and CMV-V only in the first inoculation access, although PSV-S was transmitted to only one plant
in the fourth and fifth inoculation access. These viruses may be transmitted in two phases by aphids, depending on the plant
species.
Received 16 April 1999/ Accepted in revised form 1 September 1999 相似文献
237.
Genta ITO Yuko GOTO-KOSHINO Yudai KURODA Park EUNSIL Ken MAEDA Takehisa SOMA Yasuyuki MOMOI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(11):1722
We investigated the seroprevalence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) among dogs in the Tokyo area via enzyme-linked immunosorbent assay (ELISA) using the spike protein as the target antigen. Plasma samples from 494 household dogs and blood-donor dogs were tested from July 2020 to January 2021. Of these samples, three showed optical densities that were higher than the mean plus two standard deviations of the mean of the negative-control optical densities (ODs). Of these three samples, only the sample with the highest OD by ELISA was confirmed positive by virus neutralization testing. The positive dog presented no SARS-CoV-2-related symptoms. The positivity rate of SARS-CoV-2 infections among dogs in the Tokyo area was approximately 0.2%. 相似文献