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1.
The Japanese black bear (Ursus thibetanus japonicus) is endangered for extinction in some areas of Japan, and semen collection and cryopreservation are an important means to preserve genetic resources. The aim of this study was to characterize and cryopreserve semen of free-ranging Japanese black bears. Semen was collected by electroejaculation procedure from 4 free-ranging Japanese black bears at the capture point in the field. Ejaculates containing motile sperm were recovered from all of the animals and ejaculate volume, total sperm count, % motility (percentage of motile spermatozoa), % viability (percentage of spermatozoa that excluded eosin) and % abnormal morphology (range (mean)) were 0.65-2.20 (1.51) ml, 99-1082 (490) x 10(6), 5-100 (31), 42-97 (66) and 20-87 (53), respectively. Three of the 4 ejaculates were diluted with an egg yolk-TRIS-citrate-glucose extender and cryopreserved in liquid nitrogen. Motile spermatozoa were observed after freezing and thawing in all cases. This study showed that electroejaculation would be a useful method for collecting semen from free-ranging Japanese black bears and that at least motile spermatozoa would be obtained by freezing the thus collected electroejaculates.  相似文献   
2.
ABSTRACT:   The effect of dietary taurine on juvenile Japanese flounder was determined by feeding three taurine-supplemented experimental diets (TAU) and a commercial diet (CD) to evaluate a practical diet for juvenile Japanese flounder. Juvenile Japanese flounder were reared on the three experimental diets supplemented with taurine at 0, 0.5, 1.0% and CD. These diets were fed to juvenile Japanese flounder of an initial mean body weight of 0.2 g for 6 weeks at 20°C and the taurine contents of the whole body and tissues were analyzed. The final average body weight of juvenile Japanese flounder fed the 1.0% TAU was significantly higher than that of the other groups. Taurine contents in the whole body and tissues increased with the increase in dietary taurine level. These results indicate that juvenile Japanese flounder require at least 15 mg/g taurine in the diet, even though a combined mix of fish, krill and squid meal was the main protein source in the experimental diets.  相似文献   
3.
Two 21 day experiments were conducted to determine whether microparticulate diets could be used to substitute for diatoms for raising (Experiment 1) as well as settling and on‐growing (Experiment 2) Haliotis diversicolor supertexta postlarvae. The experiments were conducted in 10 L flow‐through tanks and each diet had three replicate tanks. In experiment 1, three experimental microparticulate diets supplied by a commercial feed company, labelled SF‐15, SF‐15 (T) and JFY‐13–1, were used, and in experiment 2, SF‐15 and SF‐15 (T). Artificial diets were compared to diatoms in terms of supporting growth and survival. The survival rate for experiment 1 was lowest for JFY‐13–1 (0%) and highest for diatoms (12.9±0.8%). The final size of postlarvae fed SF‐15 and SF‐15 (T) was significantly greater than that of postlarvae fed diatoms, 973±193 μm and 996±220 μm compared to 786±141 μm. In experiment 2, a total number of 501 larvae settled onto plates covered with SF‐15, 254 on SF‐15 (T) and 1085 on diatoms. The highest survival rate was 33.1±6.9% for SF‐15 and the lowest was 17.3±5.0% for diatoms. However, the final length of postlarvae fed diatoms was significantly greater than SF‐15 and SF‐15 (T); 1018±379 μm compared to 728±89 μm and 717±90 μm. The artificial micro diets used in this study were comparable to diatoms in terms of grow and survival of postlarval H. diversicolor supertexta.  相似文献   
4.
ABSTRACT:   The effect of Artemia nauplii enriched with different level of vitamin A (VA) palmitate (1 µg = 1 IU) on the occurrence of hypermelanosis on the blind side of Japanese flounder Paralichthys olivaceus was determined. Artemia were enriched with 0, 1, 2, 5 or 10 mg VA palmitate/L (control group, and 1-, 2-, 5-, and 10-mg groups). The enriched Artemia were fed to the larvae from 27 to 31 days post hatching (dph) corresponding to the F–G stage. VA palmitate, retinol and retinoic acid (RA) contents of Artemia were correlatively elevated with increasing VA palmitate in the culture medium. RA was detected in Artemia enriched with 5 mg and 10 mg, and a significantly high frequency of hypermelanosis on the blind side was observed in these groups at 65 dph ( P  < 0.05). These results suggest that RA synthesized from VA palmitate in Artemia could induce hypermelanosis on blind side of flounder when Artemia are enriched with more than 5 mg VA palmitate/L.  相似文献   
5.
Self-incompatibility in flowering plants prevents inbreeding and promotes outcrossing to generate genetic diversity. In Solanaceae, a multiallelic gene, S-locus F-box (SLF), was previously shown to encode the pollen determinant in self-incompatibility. It was postulated that an SLF allelic product specifically detoxifies its non-self S-ribonucleases (S-RNases), allelic products of the pistil determinant, inside pollen tubes via the ubiquitin-26S-proteasome system, thereby allowing compatible pollinations. However, it remained puzzling how SLF, with much lower allelic sequence diversity than S-RNase, might have the capacity to recognize a large repertoire of non-self S-RNases. We used in vivo functional assays and protein interaction assays to show that in Petunia, at least three types of divergent SLF proteins function as the pollen determinant, each recognizing a subset of non-self S-RNases. Our findings reveal a collaborative non-self recognition system in plants.  相似文献   
6.
ABSTRACT: The present study was conducted to investigate the effects of dietary vitamin A on reproduction and egg quality in Japanese flounder Paralichthys olivaceus . Broodstock were fed experimental pellets containing two levels of vitamin A [11 × 103 IU/100 g (control diet; CD), 337 × 103 IU/100 g (experimental diet; ED)] for approximately 2 months before spawning and during the spawning period. Two groups of five females (average weight 1.4 kg) and 10 males (average weight 0.7 kg) were randomly allocated to two 30 m3 indoor tanks. Total egg production of the CD group was slightly higher than the ED group. Percentage of buoyant eggs and hatching rate of the ED group were significantly higher than the CD. In other egg quality parameters, such as percentage abnormal larvae and starvation tolerance of larvae, no notable difference was found between these two groups. At the end of the experiment, the skin color of broodstock in the ED group was darker than that of the CD group. Vitamin A content in eggs of the ED group was significantly higher than that of the CD group. However, the difference in vitamin A content in eggs between the ED and CD groups was much smaller than that in the liver of the females between the two groups. These results indicate that feeding broodstock a higher level of vitamin A increases the vitamin A content in eggs but does not affect egg quality in Japanese flounder because excess dietary vitamin A was stored mainly in the broodstocks' liver.  相似文献   
7.
In a 6-week feeding experiment, chum salmon, Oncorhynchus keta, swim-up fry, were fed fish meal diets supplemented with silkworm pupae powder (5%), dried beef liver (5%), krill meal (5%) or earthworm powder (5%) at the expense of fish meal, or substituting glucose (13%) for dextrin. Fish fed the diet with earthworm powder showed the best growth performance (675% weight gain in 6 weeks) and feed efficiency (117%). The growth rate and feed efficiency of the krill meal group were also significantly better than those of the control group (without supplement or substitution). Substitution of glucose and supplementation of silkworm pupae or beef liver failed to improve the growth rate, but significantly improved feed efficiency. Food consumption of fish fed the diet supplemented with earthworms was lowest, and none of the dietary treatments appreciably increased food intake of the fish over that of the control group. The dietary group receiving earthworm powder also showed significantly higher body fat content than the remaining dietary groups. No significant differences were noted in body protein and ash contents among all dietary treatments.  相似文献   
8.
In Asia, rice is a staple cereal crop and the continent accounts for about 90 % of the global rice production and consumption. Statistics on the areas planted with rice or production of paddy rice are fundamental to agriculture-related decisions or policy-making. Asia-Rice Crop Estimation & Monitoring (Asia-RiCE) aims to develop rice-related information, such as paddy field maps, rice growing conditions, yield, and production, using remote sensing tools and disseminate the same at the local and global scales. In this paper, we propose a methodology for the identification of rice-planted areas by using multi-temporal SAR images; a software named INternational Asian Harvest mOnitoring system for Rice (INAHOR) was developed to manipulate the proposed algorithm. The INAHOR uses the imagery observed both at the time of planting of rice and grown-up stages. In this study, two thresholds needed for the INAHOR were optimized based on the detailed land cover data collected through a field survey. Rice-planted areas across the study area in Japan were identified by the INAHOR using the RADARSAT-2 Wide Fine beam mode data. The classification results of RADARSAT-2 VV and VH polarizations were compared. The data with VH polarization showed a higher total accuracy of 83 % with ?20.5 dB and 3.0 dB for the minimum and range thresholds, respectively. The INAHOR is currently being used with the RADARSAT-2, ALOS, and ALOS-2 SAR data in the Southeast Asian countries to assess the robustness of the thresholds and classification accuracies under the framework of Asia-RiCE.  相似文献   
9.
脱落酸(Abscisic acid, ABA)对映异构体的生物活性比较   总被引:2,自引:0,他引:2  
 采用新方法精制脱落酸(ABA)异构体试样,改变以往靠光学离析法分离racemic型(SR)-(±)-ABA,提高了(S)-(+)-ABA与(R)-(-)-ABA两镜像体纯度。抑制生长试验和残留量分析结果表明:天然型(S)-(+)-ABA活性,显着高于非天然型(R)-(-)-ABA或(SR)-(±)-ABA活性。抑制莴苣种子发芽50%的活性强度(S)-(+)-ABA约是(R)-(-)-ABA的5倍,(SR)-(±)-ABA介于二者之间。抑制萝卜下胚轴生长试验,最显着有效期2~6天,(6天后差异渐小,8日甚微),生理作用期约为一周,(S)-(+)-ABA活性是(R)-(-)-ABA的3.6倍。差异原因可能是两异构体分子立体结构不同所致。  相似文献   
10.
不同玉米品种萌芽期及苗期抗旱性初步研究   总被引:15,自引:4,他引:15       下载免费PDF全文
对4个玉米杂交种辽单35、丹玉24、沈丹16、沈农87进行萌芽期和苗期的抗旱性研究.结果表明,不同杂交种在抗旱性上存在明显差异,在水分胁迫下,抗旱性强的杂交种仍然保持较高的发芽势和发芽率,苗期叶片气孔导度、蒸腾速率、光合速率下降的幅度较小。  相似文献   
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