Changes in sexual behavior and fecal steroid hormone concentrations during the breeding season in female Hokkaido brown bears (Ursus arctos yesoensis) under captive condition     

Ishikawa A  Sakamoto H  Katagiri S  Takahashi Y 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2003,65(1):99-102

The longitudinal changes in fecal steroid hormone concentrations and sexual behavior in 2 mated/pregnant and 3 non-mated female Hokkaido brown bears were investigated during the breeding season. Behavioral estrus (standing) lasted for 14 and 32 days in the mated females and for 25 to 36 days in the non-mated females. In non-mated females, sexual behavior, such as female-female mounting and masturbation, was observed for several days before and after the estrous period. In mated females, mean fecal estradiol-17beta concentrations were higher in the estrous period than in the post-estrous period, while fecal progesterone concentrations were higher in the post-estrous period than in the estrous period. The similar trends of steroid hormone changes were observed in the non-mated females.  相似文献   

Steroid hormones do not reactivate Neospora caninum in ovariectomized mice     

Kobayashi A  Katagiri S  Kimura T  Ochiai K  Umemura T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2002,64(9):773-777

The direct effects of three steroid hormones (progesterone, estradiol-17beta and corticosterone) on the growth of Neospora caninum (N. caninum) tachyzoite were examined in Vero cells. Subsequently, ovariectomized BALB/c mice infected with N. caninum were treated with physiological concentrations of the steroid hormones for 1 or 2 weeks. These hormones had no direct effect on the parasite growth in vitro. In the infected mice, there was no significant difference in the parasite distribution and histopathological changes between the hormone-injected and control groups. No mice showed parasitemia at the time of autopsy. These results suggest that physiological levels of steroid hormones (progesterone, estradiol-17beta and corticosterone) do not reactivate N. caninum in mice.  相似文献   

Effects of sika deer browsing on the arthropod communities on understory vegetation in a thinned Japanese cypress plantation     

Nana Katagiri  Naoki Hijii 《Journal of Forest Research》2015,20(3):347-356

  相似文献   

Genetic and physical mapping of the partial resistance gene, pi34, to blast in rice   总被引：1，自引：0，他引：1  

Zenbayashi-Sawata K  Fukuoka S  Katagiri S  Fujisawa M  Matsumoto T  Ashizawa T  Koizumi S 《Phytopathology》2007,97(5):598-602

ABSTRACT Partial resistance to rice blast in the Oryza sativa japonica group cv. Chubu 32 is controlled by Pi34, a major quantitative trait locus (QTL) on chromosome 11, and several uncharacterized QTLs. The objectives of the study were (i) high-resolution genetic and physical mapping of Pi34 and (ii) identification of new QTL imparting resistance to rice blast. Chubu 32 was crossed with a susceptible chromosomal segment substitution line (CSSL) of cv. Koshihikari. From 4,012 of segregating individuals, 213 recombinants in the Pi34 region were screened by using polymerase chain reaction-based markers and tested resistance in the field and greenhouse. The Pi34 locus is located in the 54.1-kb region on the genomic sequence of cv. Nipponbare. We constructed a bacterial artificial chromosome (BAC) library of Chubu 32, selected the clone containing Pi34, and sequenced it. The Pi34 locus consequently was located on an interval of 65.3 kb containing 10 predicted open reading frames (ORFs). Two of these ORFs were predicted only in Chubu 32 and encoded transposable elements. The other eight ORFs were found in both Chubu 32 and Nipponbare and one of them, which encoded an unknown protein, showed significantly different amino acid sequences between two cultivars. The new QTL, Piq6(t), was detected on the short arm of chromosome 6 and the genetic distance of flanking markers was 16.9 centimorgans in Nipponbare. Pi34 and Piq6(t) acted additively on resistance to rice blast but the effect of Piq6(t) was relatively small compared with Pi34.  相似文献   

PMSG profiles in superovulated and anti-PMSG antiserum treated mice and heifers with enzymeimmunoassay     

S Katagiri  Y Takahashi  M Hishinuma  H Kanagawa  O Dochi  H Takakura 《The Japanese journal of veterinary research》1991,39(1):11-21

A sandwich enzymeimmunoassay (EIA) for pregnant mare serum gonadotropin (PMSG) using a microtiter plate was developed. Sensitivity of the assay to PMSG was 15.6 mIU/ml (0.2 ng/well). The PMSG levels in serum were measured with the EIA in superovulated and anti-PMSG rabbit antiserum treated mice and heifers. In mice, the PMSG blood level was measurable in the serum 4-6 days after intraperitoneal injection of 5-30 IU of PMSG. The administration of anti-PMSG antiserum at the same dose level as PMSG caused a rapid decrease in the PMSG blood level, declining to undetectable levels within 17 hours. In heifers, the PMSG level was measurable at 10-11 days after the injection of 2500 or 3000 IU of PMSG. When antiserum was injected 48 hours after the PMSG injection, the clearance rate of PMSG was affected by the route of the administration. The administration of 3000 units of anti-PMSG antiserum intravenously caused a rapid decline and the disappearance of circulating PMSG within 17 hours. When 3000 units of anti-PMSG antiserum was injected intra-muscularly, the PMSG blood level also decreased and became unmeasurable 24 hours after administration; however, it was still detectable for up to 17 hours. These results indicate that the administration of anti-PMSG antiserum at the proper timing and dosage could lead to successful superovulation through the improvement of hormonal conditions.  相似文献   

Effect of incubation temperature or maternal antibody on virus growth and mortality of embryonated chicken eggs inoculated with the B1 strain of lentogenic Newcastle disease virus     

S Yachida  S Aoyama  N Takahashi  Y Iritani  K Katagiri 《Avian diseases》1979,23(4):983-988

The effects of incubation temperature on virus growth and mortality patterns were studied in antibody-free chicken eggs inoculated with the B1 strain of Newcastle disease virus. Embryo mortality patterns did not differ much between 37, 39, and 41 C of incubation, although virus growth curves were higher at 39 C and 41 C than at 37 C. Below 35 C, embryo mortality was delayed, although from 48 hours after incubation the virus growth curves were similar to those at 37 C. In eggs with and without maternal antibody, virus titers were maximum 48 hours after incubation, although slightly higher in antibody-free eggs than in eggs with antibody whether the eggs were alive or dead. Eggs with maternal antibody had delayed mortality patterns.  相似文献   

Effects of oxygen tension in the gas atmosphere during in vitro maturation, in vitro fertilization and in vitro culture on the efficiency of in vitro production of mouse embryos   总被引：2，自引：0，他引：2  

Adam AA  Takahashi Y  Katagiri S  Nagano M 《The Japanese journal of veterinary research》2004,52(2):77-84

Effects of oxygen (O2) tension in the gas atmosphere during in vitro maturation (IVM), in vitro fertilization (IVF) and in vitro culture (IVC) on the efficiency of in vitro production of mouse embryos were examined. Mouse oocytes recovered from large antral follicles were subjected to IVM in Waymouth medium for 15, 16 and 17 hr under 5 or 20% O2 and then subjected to IVF and IVC under 5 or 20% O2 tension. Lowering the O2 tension in the gas atmosphere for IVM from 20 to 5% improved the cleavage rate after IVF when the oocytes were subjected to IVM for 15 hr; however, no improvement in the cleavage rate was observed when the culture period for IVM was extended to 16 and 17 hr. Lowering the O2 tension to 5% for IVM and IVC improved the development of the cleaved oocytes to the blastocyst stage, regardless of the culture period for IVM. However, the O2 tension for IVF had no remarkable effect on the subsequent embryonic development. These results demonstrate that 5% O2 is superior to 20% O2 for IVM and IVC, and suggest that 20% O2 for IVM may delay oocyte maturation and/or the acquisition of fertilizability and impair the developmental competence of oocytes.  相似文献   

A Comparison of the Effects of Two Prey Enrichment Media on Growth and Survival of Pacific Bluefin Tuna,Thunnus orientalis,Larvae          下载免费PDF全文

Maria S. Stein  Daniel Margulies  Jeanne B. Wexler  Vernon P. Scholey  Katagiri Ryo  Tomoki Honryo  Tsukasa Sasaki  Angel Guillen  Yasuo Agawa  Yoshifumi Sawada 《Journal of the World Aquaculture Society》2018,49(1):240-255

Three experiments were conducted to investigate the growth, survival, and standardized cohort biomass of Pacific bluefin tuna, Thunnus orientalis, larvae fed nutritionally enhanced prey during the first week of feeding using two commonly used, commercially available enrichment media, AlgaMac Enrich and Marine Glos. T. orientalis larvae exhibited exponential growth in standard length and dry weight. The daily specific growth rates in length and weight are the first reported for T. orientalis larvae and the averages ranged from 3.8 to 4.1% and 27.5%, respectively, for larvae in the AlgaMac treatment and from 4.1 to 6.1% and 31.5%, respectively, in the Marine Glos treatment. Average daily growth rates in length ranged from 0.16 to 0.23 mm/d for larvae in the AlgaMac treatment and from 0.17 to 0.27 mm/d for those in the Marine Glos treatment. Daily growth rates in length were similar to those reported for other tuna larvae reared in the laboratory but slower than most published estimates for larval tunas in situ at similar water temperatures. Mean prey number per gut was positively associated with mean prey level in the tank. Both enrichment media appear to be good sources of nutritional improvement of planktonic prey for T. orientalis larvae.  相似文献   

Effects of follicle‐stimulating hormone followed by gonadotropin‐releasing hormone on embryo production by ovum pick‐up and in vitro fertilization in the river buffalo (Bubalus bubalis)     

Kenichiro Sakaguchi  Excel Rio S. Maylem  Ramesh C. Tilwani  Yojiro Yanagawa  Seiji Katagiri  Edwin C. Atabay  Eufrocina P. Atabay  Masashi Nagano 《Animal Science Journal》2019,90(5):690-695

In this study, we examined the effects of superstimulation using follicle‐stimulating hormone (FSH) followed by gonadotropin‐releasing hormone (GnRH) on buffalo embryo production by ultrasound‐guided ovum pick‐up (OPU) and in vitro fertilization (IVF). Nine Murrah buffaloes were subjected to OPU‐IVF without superstimulation (control). The morphologies of the oocytes collected were evaluated, and oocytes were then submitted to in vitro maturation (IVM). Two days after OPU, same nine buffaloes were treated with twice‐daily injections of FSH for 3 days for superstimulation followed by a GnRH injection. Oocytes were collected by OPU 23–24 hr after the GnRH injection and submitted to IVM (the superstimulated group). The total number of follicles, number of follicles with a diameter > 8 mm, and number of oocytes surrounded by multi‐layered cumulus cells were higher in the superstimulated group than in the control group (p ≤ 0.05). After IVF, the percentages of cleavage and development to blastocysts were higher in the superstimulated group than in the control group (p < 0.05). In conclusion, superstimulation improved the quality of oocytes and the embryo productivity of OPU‐IVF in river buffaloes.  相似文献   

In vitro fertilization and cortical granule distribution of bovine oocytes having heterogeneous ooplasm with dark clusters.   总被引：1，自引：0，他引：1  

M Nagano  Y Takahashi  S Katagiri 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》1999,61(5):531-535

In vitro maturation, fertilization and subsequent development of oocytes with homogeneous (category 1), or heterogeneous ooplasm (category 2) were investigated. No significant differences were observed in the nuclear maturation and total fertilization rates between the two categories. However, category 2 oocytes showed a higher normal fertilization rate due to their lower incidence of polyspermy as compared to category 1 oocytes. Electron microscopic study revealed that all category 2 oocytes had cortical granules lined up next to the plasma membrane, and that some category 1 oocytes still had small clusters of cortical granules after maturation. Although the proportion of cleaved zygotes was higher in category 2, the percentages of cleaved zygotes that developed to the blastocyst stage did not differ between the two categories. These results demonstrate that oocytes with heterogeneous ooplasm have a higher capacity for normal fertilization due to the reduction in polyspermy. This can be attributed to the normal distribution of cortical granules in category 2 oocytes after maturation.  相似文献