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Kenichi OTAWA Masaaki SATO Takako SASAKI Hiraku SASAKI Jun NONAKA Kikuji ITO Toshio KUROKI Yutaka NAKAI 《Animal Science Journal》2004,75(3):261-269
The ecology of shiga‐toxigenic Escherichia coli (STEC) is important in the animal production environment. We investigated fecal shedding of STEC in one town in Miyagi, Japan by multiplex polymerase chain reaction (PCR) targeting shiga toxin gene 1 (stx1), gene 2 (stx2) and malB promoter gene, and analyzed the PCR products of stx1 or stx2 (54 samples) by direct sequencing. Three of 46 (6.5%) beef cattle in the University Farm of Tohoku University (Kawatabi Farm) and 11 of 70 (15.7%) calves in neighboring dairy farms carried STEC. Rate of detecting genes of stx1, stx2 and stx1+2 was 3.4% (4/116), 8.6% (10/116) and 0.9% (1/116), respectively. Serotyping indicated that STEC contaminated farms at different times or through different routes. Isolates harbored no mutation among stx1, but six (Kawatabi Farm) and 38 (neighboring farms) base substitutions among stx2, respectively. The diversity of substitutions of stx2 was observed among farms or even in a farm. Phylogenic analysis revealed that STEC detected in the area were classified into three clusters by the variety of stx2. Sequence analysis of stx2 will be one of the tools for clarifying the source of outbreaks and the route of contamination of STEC. 相似文献
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Boniface Baboreka KAYANG Miho INOUE-MURAYAMA Hideaki TAKAHASHI Mitsuru MINEZAWA Masaoki TSUDZUKI Makoto MIZUTANI Shin'ichi ITO 《Animal Science Journal》2003,74(4):255-259
Twenty‐eight original chicken microsatellite markers were isolated and characterized to determine their utility as cross‐reactive markers for comparative genetic mapping in the order Galliformes. Primer pairs were typed in 12 unrelated chickens and also tested on Japanese quail and helmeted guinea fowl deoxyribonucleic acid (DNA). Polymorphism was observed in 23 (82.1%) of the markers and the average number of alleles per locus was 2.9 while the mean heterozygosity was 0.19. Eleven (39.3%) of the chicken markers cross‐reacted with Japanese quail DNA and 2 (7.1%) with helmeted guinea fowl DNA. The cross‐reactive markers described would serve as useful resources for comparative genetic mapping in poultry species belonging to the order Galliformes. 相似文献
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Go SEHATA Hiroaki SATO Toshihiro ITO Yoshitaka IMAIZUMI Taichi NORO Eiji OISHI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(7):851-855
We used real-time RT-PCR and virus titration to examine canine distemper virus
(CDV) kinetics in peripheral blood and rectal and nasal secretions from 12 experimentally
infected dogs. Real-time RT-PCR proved extremely sensitive, and the correlation between
the two methods for rectal and nasal (r=0.78, 0.80) samples on the peak day of viral RNA
was good. Although the dogs showed diverse symptoms, viral RNA kinetics were similar; the
peak of viral RNA in the symptomatic dogs was consistent with the onset of symptoms. These
results indicate that real-time RT-PCR is sufficiently sensitive to monitor CDV
replication in experimentally infected dogs regardless of the degree of clinical
manifestation and suggest that the peak of viral RNA reflects active CDV replication. 相似文献
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Kensuke HIROSE Tatsuya TAKIZAWA Kazuo FUKAWA Tetsuya ITO Masayuki UEDA Yoichi HAYASHI Kazuaki TANAKA 《Animal Science Journal》2011,82(1):46-51
A C?T single nucleotide polymorphism (SNP) on exon 24 of the porcine class 3 phosphoinositide‐3‐kinase (PIK3C3) gene is considered a possible genetic marker for selecting backfat (BF) thickness and carcass fat, although only one study has published results on its effects by performing experiments on a single resource family. We analyzed the association of this PIK3C3 polymorphism with production traits in 739 Duroc pigs. The C allele frequency was 67.9% in our study population. PIK3C3 polymorphism showed significant effects on average daily weight gain (ADG), BF thickness, intermuscular fat content (IMF), and the size of the loin eye muscle area (EMA). The C alleles increased ADG, BF and IMF, and decreased EMA. The predicted differences in traits between the homozygous pigs of the C and T alleles were 40 g/day for DG, 1.2 mm for BF, 0.44% for IMF, and 1.6 cm2 for EMA. Furthermore, the statistical models for estimating the breeding values of each trait had lower Akaike's information criterion values when adding PIK3C3 genotype information. We therefore confirmed that the polymorphism in PIK3C3 (C2604T) has the potential to be a genetic marker for production traits in Duroc pigs. 相似文献
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Satoshi KUSUDA Hisashi HASHIKAWA Masato TAKEDA Hideki ITO Atsushi GOTO Jun OGUCHI Osamu DOI 《The Journal of reproduction and development》2013,59(3):308-313
The purposes of the present study were to clarify age- and season- related androgen
patterns, and to compare the reproductive physiology between Japanese captive koala
populations and Australian populations. To measure fecal androgens, feces were collected
from male koalas (4.2 to 13.8 years of age) kept in Japanese zoos. Fecal androgens were
extracted with methanol from the lyophilized samples and determined by enzyme immunoassay
using 4-androstene-3,17-dione antibody. Fecal androgen concentration in male koalas
increased after sexual maturation and remained relatively high until old age. In the
survey with the Japanese zoo studbook of koalas, copulation (conception) month showed a
pyramid shape with a peak in March to June (60.7%) in koalas born and reared in Japanese
zoos and from July to April with the highest concentration in September to January (69.7%)
in Australian institutes. Japanese zoo koala populations have a characteristic
physiological cycle adapted to Japan''s seasonal changes. The suitable month of year for
copulation or conception in Japan is diametrically opposed to that in Australia. Mean
fecal androgen concentrations by month in the males born and reared in Japan indicated
annual changes with the highest concentration in May and the lowest value in November.
Fecal androgen analysis may be a noninvasive alternative tool to monitor circulating
testosterone and may be helpful in understanding reproductive activity and physiology in
male koalas. 相似文献
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Ryoka MIYAKE Takakaki ITO Hiroshi KAMATA Rui KANO 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(7):1090
We isolated ascomycetous yeasts including Candida species, that originally belonged to the genus Candida, from bulk milk in the Aichi area of Japan, and determined the minimum inhibitory concentrations (MICs) of antifungal drugs on these isolates by conducting E-tests. We isolated 7 human pathogenic species (14 isolates) from 14 bulk milk samples: 5 Candida species of yeasts, and 2 Candida-related species. Two isolates of C. albicans and C. inconspicua were resistant to fluconazole (MIC >32 mg/l). One isolate of C. krusei was resistant to both azoles (fluconazole: >256 mg/ml and itraconazole: 4 mg/l). One isolate of C. catenulata might be resistant to amphotericin B (>32 mg/l). 相似文献
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At fertilization, the sperm triggers resumption from the arrest, extrusion of the second polar body and pronuclear formation, the events of which are collectively acknowledged as ‘oocyte activation’. In all species up to date, oocyte activation requires a fertilization‐associated increase in the intracellular concentration of calcium. Especially in mammals, the signal of intracellular calcium rise at fertilization consists of periodical rises, which are also referred to as calcium oscillations. Our recent results suggest that these calcium oscillations have an important role in not only oocyte activation but also development of mammals. Pigs are animals of great agricultural value and ones in which assisted reproductive techniques, including somatic cell nuclear transfer, to produce gene‐modified pigs. Although reconstructed embryos require artificial activation stimuli which mimic fertilization‐associated increase of intracellular calcium in the oocytes, it has been known that the developmental ability of the oocytes after artificial activation is low and the regimen seems to be required for improvement. Recently we focused on two molecules, phospholipase C zeta and inositol 1,4,5‐triphosphate receptor which have important roles in regulation of calcium oscillations during fertilization in mammals, including pigs. In this review, we will discuss the present status and future perspective of molecular mechanisms during fertilization in pigs. 相似文献
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Md. Tofazzal ISLAM Toshiaki ITO Satoshi TAHARA 《Journal of General Plant Pathology》2001,67(4):255-261
The behavioral and morphological diversity of intact zoospores of Aphanomyces cochlioides and their dynamic morphological changes when interacting with the host or a host-specific zoospore attractant were studied
by light and electron microscopy. The reniform-ovate zoospore has two heterokont flagella, both inserted in a ventral groove.
The anterior flagellum possesses two rows of tripartite tubular hairs (TTHs) distributed throughout its length, whereas the
posterior flagellum was ornamented with two rows of highly dense fine tubular hairs, except on its tapered terminal part.
The tip of the posterior flagellum has a bunch of similar fine hairs like those on the flagellum shaft. The biflagellated
zoospores quickly aggregated on the host (spinach) root, adhered to the root surface, encysted by shedding or retracting the
flagella, germinated at a fixed point to form germ tubes, and finally invaded the root tissues via the appressoria within 50–60 min. This precise homing response of A. cochlioides zoospores reflects guidance by a host-specific signal(s) for locating potential infection sites, differentiation of zoospores
to cystospores, formation of infection structures and/or germ-tube tropism for completing pre-infection events in haste. Prior
to the encystment, the posterior flagellum may be involved in successful docking on the root surface by tip contact followed
by shedding or retraction.
Received 22 January 2001/ Accepted in revised form 28 May 2001 相似文献