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51.
In China, the first Przewalski’s horse (Equus przewalskii) group was released in
Kalamaili Ungulate Protected Area in Xinjiang, in August 2001. The objective of this study
was to investigate reproduction and development of released Przewalski’s horses in
Xinjiang, China from 2002 to 2006. Twenty-four descendants were naturally born, average
reproduction rate was 38.7%, and average survival rate of foals was 69.1% in this interim.
Frequent alternation of the leading stallion and infertility in female horses due to
environmental factors were main causes for the low reproduction rate. The infant mortality
rate of released Przewalski’s horses was 25.0%, and 83.3% of death in infants was due to
the leading stallion infanticide. The released Przewalski’s horses exhibited seasonal
breeding, 70.8% of infants were born in May and June. The fertility rates were 8.3% in
April and 37.5% in May, which were lower compared to those of the captive Przewalski’s
horse groups (18.3% and 44.3%, respectively). Furthermore, the fertility rate in June was
33.3% and higher than the captive groups (18.3%). These findings showed that the breeding
peak of the released Przewalski’s horse groups was later than the captive groups, and
suggested that the altered survival environment and food supplies were the main reasons
contributing to the delayed breeding peak. 相似文献
52.
Saeid Moharramipour Kazuyoshi Takeda Kazuhiro Sato Hideya Yoshida Hisaaki Tsumuki 《Euphytica》1999,106(2):181-185
The inheritance of gramine indole alkaloid was studied in F1 and F2 generations derived from crosses between wild ( Hordeum
vulgare subsp. spontaneum) and cultivated ( H. vulgare subsp. vulgare) barley at adult stage in the field. The means of gramine
content were very low in F1s and F2s in April and May. The ratio of progeny containing gramine to those without gramine (near
zero or undetectable) fit a mono-genic or di-genic model in F2 generation. However, the content of gramine might be controlled
by minor genes in the gramine-containing plants. The direction of dominance was toward lower gramine content. The averages
of dominance ( h/d) in F1 and F2 ranged from partial to complete. Broad-sense heritabilities were high (0.70 to 0.77). The
usefulness of hybrids for breeding aphid resistance and possibility increasing palatability of grazing pasture for sheep and
cattle is discussed.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
53.
Muhammad M. Mackeen Abdul M. Ali Mohd A. Abdullah Rozita M. Nasir Nashriyah B. Mat Abdul R. Razak Kazuyoshi Kawazu 《Pest management science》1997,51(2):165-170
Methanolic extracts of 79 Malaysian plants representing 42 families were assessed for antinematodal activity against Bursaphelenchus xylophilus using a fungal-feeding assay. Extracts of 27 plants from 19 families showed antinematodal activity, while 52 species were inactive. Five extracts (Sauropus androgynus, Eugenia polyantha, Areca catechu, Piper betle and Piper nigrum) exhibited very strong activity against Bursaphelenchus xylophilus at a minimum effective dose (MED) of 0·625 mg per ball. Strong antinematodal activity (MED: 1·25–2·5 mg per ball) was shown by the extracts of Spondias cyntherea, Codiageum variegatum, Euodia glabra and Cicca acida. Eleven extracts (Carica papaya, Ipomoea aquatica, Ocimum basilicum, Leea gigantea, Pithecellobium jiringa, Crypteronia paniculata, Myristica fragrans, Murraya koenigii, Leucaena leucocephala, Melastoma malabathricum and Morinda citrifolia) demonstrated moderate activity between MED of 5 and 10 mg per ball, and weak activity was observed in seven extracts (Ipomoea batatas, Cymbopogon citratus, Garcinia atroviridis, Psophocarpus tetragonolobus, Tamarindus indica, Allium odorum and Stenochalaena palustris). © 1997 SCI 相似文献
54.
Tanaka Tatsuya Ikeda Ryunosuke Yuta Yuta Tsurukawa Kanji Nakamura Satoshi Yamaguchi Takeharu Komeyama Kazuyoshi 《Fisheries Science》2019,85(6):1037-1043
Fisheries Science - In aquaculture, periodic measurement of fish body size is required to suitably assess growth progress. The aim of this study is to monitor the growth of free-swimming red sea... 相似文献
55.
Noboru SASAKI Thandar OO Yoshikazu YASUDA Takahiro ICHISE Noriyuki NAGATA Nozomu YOKOYAMA Kazuyoshi SASAOKA Keitaro MORISHITA Shouta MM NAKAYAMA Mayumi ISHIZUKA Kensuke NAKAMURA Mitsuyoshi TAKIGUCHI Yoshinori IKENAKA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(11):1634
We developed an analytical method using an on-line column-switching liquid chromatography with triple quadrupole mass spectrometry (LC/MS/MS) for quantifying multiple steroids in serum. Using the developed method, we evaluated the serum concentration of nine steroids (cortisol, corticosterone, cortisone, 11-deoxycortisol, 21-deoxycortisol, deoxycorticosterone, progesterone, 17α-OH-progesterone and aldosterone) in dogs with hyperadrenocorticism (HAC). Serum was mixed with stable isotope internal standards and thereafter purified by the automated column-switching system. The limit of detection ranged 2–16 pg/ml for nine steroids. In the baseline samples, five steroids (cortisol, corticosterone, cortisone, 11-deoxycortisol, and 17α-OH-progesterone) were detected in all dogs. The concentrations of cortisone, 11-deoxycortisol, and 17α-OH-progesterone in dogs with HAC (n=19) were significantly higher those in dogs without HAC (n=15, P<0.02). After the adrenocorticotropic hormone stimulation test, six steroids (cortisol, corticosterone, cortisone, 11-deoxycortisol, 17α-OH-progesterone, and deoxycorticosterone) were above the limit of quantification in all dogs. Cortisol, corticosterone, cortisone, and deoxycorticosterone concentrations of dogs with HAC were significantly higher than those of dogs without HAC (P<0.02). In addition, 11-deoxycortisol and 17α-OH-progesterone concentration was higher in dogs with HAC than in dogs without HAC (P=0.044 and P=0.048, respectively). The on-line column-switching LC/MS/MS would be feasible for measuring multiple steroids in dog serum. The results suggest that cortisone, 11-deoxycortisol, and 17α-OH-progesterone would be related to HAC. Further studies are warranted to assess the clinical feasibility of steroid profile in dogs with HAC. 相似文献
56.
Kazuyoshi Hosaka 《American Journal of Potato Research》2004,81(2):153-158
Potato was domesticated in the Andes of South America. However, the presently worldwide-grown potato (Solanum tuberosum L. ssp.tuberosum, 2n=4x=48) has characteristic T-type chloroplast DNA that was introduced after late blight epidemics in the mid-19th century from the Chilean potato (2n=4x=48) grown in the southern coastal regions in Chile. Among many wild potato species, the same chloroplast DNA was found only in some populations of a diploid speciesS. tarijense Hawkes (2n=2x=24), which ranges from central Bolivia to northwest Argentina. To elucidate an evolutionary pathway of T-type chloroplast DNA fromS. tarijense to Chilean potato, 215 accessions ofS. stenotomum Juz. et Buk., considered to be the most primitive, diploid cultivated potato species, from which all the Andean cultivated species evolved, and 286 accessions of the most widely grown, Andean tetraploid cultivated speciesS. tuberosum L. ssp.andigena Hawkes (2n=4x=48) were examined in this study. No accession ofS. stenotomum had T-type chloroplast DNA, while nine accessions, mostly from northwest Argentina, ofS. tuberosum ssp.andigena had T-type chloroplast DNA. Therefore, I conclude that some populations ofS. tarijense having T-type chloroplast DNA were naturally crossed as female withS. tuberosum ssp.andigena from which the Chilean potato was selected. 相似文献
57.
Daito T Fujino K Watanabe Y Ikuta K Tomonaga K 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2011,73(9):1243-1247
Borna disease virus (BDV) is a non-segmented, negative-strand RNA virus that is characterized by nuclear replication and persistent infection. A unique feature of BDV is that it releases only a small number of infectious particles from infected cells. Although these characteristics might make it difficult to obtain a large amount of recombinant viruses in a reverse genetics system, the mechanism underlying the budding or assembly of BDV particle has remained largely unknown. In this study, as a first step toward understanding the virion formation of BDV, we investigated the intracellular distribution and mobility of the fluorescent marker fusion envelope glycoprotein (G) of BDV in living cells. Expression analysis revealed that fusion proteins seem to cleave into functional subunits and localize in the endoplasmic reticulum (ER)/Golgi apparatus, as well as the authentic BDV G. Furthermore, we demonstrated using fluorescence recovery after photobleaching analysis that BDV G fluorescence shows rapid recovery in both the ER/Golgi and plasma membrane regions, indicating that BDV G fusion protein may be a useful tool to investigate not only the maturation of BDV G but also the budding and assembly of BDV particles in living cells. 相似文献
58.
Jian Feng Ma Aki Higashitani Kazuhiro Sato Kazuyoshi Takeda 《Soil Science and Plant Nutrition》2013,59(7):1115-1117
Abstract Iron deficiency in humans is the most prevalent micronutrient deficiency worldwide. To screen for high Fe cultivar, genotypic variation in Fe concentration of barley grain was investigated in two collections of barley: 274 standard varieties selected at the Barley Germplasm Center of the Research Institute for Bioresources, Okayama University (SV) and 135 varieties from the Barley Core Collection of Americas (BCCAM). The Fe concentration of barley grain showed large variation, ranging from 24.6 to 63.3 mg kg?1 in SV, from 21.0 to 83.0 mg kg?1 in BCCAM barleys. The Fe concentration was not affected by the key characters of barley varieties, kernel row types, and hulled or hull-less. The Fe concentration was also not related to the place of origin of the barley variety. About 90% of total Fe was localized in the grain without hull. These results provide fundamental data for breeding Fe-rich cultivars and for studying the mechanisms involved in genotypic variation in Fe concentration. 相似文献
59.
The silicic acid adsorption by a soil (Eutric Gleysols) where slag fertilizers were applied was measured by the addition of a silicic acid solution labelled with 30Si after soil incubation, in order to study the effect of slag application on the specific Si adsorption by the soil and to estimate the amount of Si in the soil solid phase which can easily enter the soil solution. It was evident that the application of slags increased the ability of soil to adsorb Si. It was also shown that the 30Si added was diluted with not only the Si present in the soil solution but also the Si dissolved from the soil solid phase. We proposed the use of the term “active” for Si in soil which can take part in the isotopic dilution within 1 h. The amount of active Si in the soil solid and liquid phases (D 60 - value) was calculated from the 30Si content in the soil solution and compared with the amount of Si taken up by rice plant (Oryza sativa L.), which was determined in our previous study. The buffering capacity of the soil for Si, which can reflect the ability of soil to maintain the Si concentration in the soil solution constant when Si is added to or removed from the soil, was also determined. The D 60 - value and the Si buffering capacity of the soil increased by slag application. These increases were large when the alkalinity of the applied slags was high. The correlation study revealed that the D 60 - value was a better index of Si availability of the soil than the amount of Si dissolved from the soil solid phase during the incubation when the slags were previously applied. 相似文献
60.
Kazuyoshi Hosaka 《American Journal of Potato Research》2003,80(1):21-32
The highly heterozygous and tetraploid nature of potato (Solanum tuberosum L. ssp.tuberosum) has hampered discovery of its wild ancestral species. Chloroplast DNA is a very reliable indicator to trace maternal ancestry of crops. Most of the common potato (grown worldwide) has unique, T-type chloroplast DNA derived from Chilean cultivated potato (both areS. tuberosum ssp.tuberosum). Analyzing seven different chloroplast DNA markers, I found all the T-type accessions of cultivated potatoes shared the same chloroplast DNA haplotype only with some accessions ofS. tarijense Hawkes and its derived hybrids. Thus, I conclude that some populations ofS. tarijense acted as the maternal ancestor of potato. 相似文献