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91.
Agustinus P Harahap Akihiro Takemura Shigeo Nakamura MD Saydur Rahman Kazunori Takano 《Fisheries Science》2001,67(5):888-893
ABSTRACT: This study clarifies the annual reproductive cycle and the lunar-synchronized spawning of the spiny rabbitfish ( Siganus spinus ) that inhabit the Okinawan waters. Annual and weekly changes in the gonadosomatic index (GSI) and the histological features of the ovaries were checked. Gonadosomatic index was high during the months of May to July, and yolk-laden oocytes were observed in the ovaries from March to July. Some of the ovaries collected during June and July contained oocytes at maturation stage or ovulatory follicles. These results suggest that the spiny rabbitfish undergo active vitellogenesis and spawning from May to July. During the reproductive season (May to July), collection of fish according to the lunar phase revealed that a high GSI occurred around the time of the new moon. Cyclic oocyte development with peaks around the time of the same moon phase was also observed, suggesting that, in Okinawan waters, this species is a lunar-synchronized spawner and spawns three times. 相似文献
92.
Tsuneo Sato Tomomi Higuchi Hisashi Shibuya Shigeo Ohba Sadao Nogami Wataru Shirai Hideaki Watanabe Shigeaki Honda 《Journal of zoo and wildlife medicine》2002,33(4):367-370
A 28-yr-old female California sea lion (Zalophus californianus) in a commercial aquarium developed an ulcerated lingual tumor and died. Necropsy revealed a moderately differentiated squamous cell carcinoma. Immunohistochemical staining and electron microscopic studies revealed that the tumor cells were strongly positive with anti-keratin-cytokeratin antibody and had abundant tonofibrils and desmosomes. The neoplasm had metastasized to a mandibular lymph node. 相似文献
93.
Seki M Asano K Ishigaki K Iida G Teshima K Watari T Tanaka S 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2011,73(5):693-696
A 13-year-old neutered female Shih Tzu was referred for investigation of a cranial abdominal mass. Investigations including conventional radiography, abdominal ultrasonography and computed tomography confirmed the mass in the caudate lobe of the liver. As a collateral vein originating from the caudal vena cava (CVC) communicated with the azygos vein, the CVC was ligated and transected cranial to the right renal vein and cranial to the mass under temporary occlusion of the thoracic descending aorta and posthepatic CVC. The mass combined with the CVC was excised. The mass was confirmed as hepatocellular carcinoma (HCC). This report describes the first case with successful en bloc resection of a large HCC involving the CVC in a dog. 相似文献
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95.
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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99.
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
100.
Taro Takahashi Hideo Aizaki Takeshi Sato Na Guo Yasuhiro Nakashima Shigeo Ogawa Nanae Yamada Xiaoyun Zheng 《Paddy and Water Environment》2013,11(1-4):503-511
Of the plethora of studies that discuss requirements for successful irrigation management, few pay close attention to what actually happens when the supply of water becomes extremely low. Such an oversight in the literature is unfortunate, because this is precisely when management matters. To understand what separates success from failure in irrigation management at times of critical water shortages, the authors conducted emergency fieldwork in February 2010 along four major irrigation channels in a drought-stricken rice-growing area within the Chinese province of Yunnan. Separately, satellite images of the four villages dated February 2009 and February 2010 were jointly analysed to produce a novel indicator for a village’s success in water management. Called the in-crisis delivery rate, this indicator compares water delivery between normal and drought years and directly evaluates performance in water management during crisis periods. The results led to an unexpected discovery that, contrary to common expectations, the only village of the present study that deployed a traditional earthen water channel secured substantially more water throughout the drought period than those with concrete-lined channels. It is hypothesised that the labour intensive, rather than capital intensive, nature of repair work of the earthen channel enabled flexible operations, and hence had the comparative advantage under a skilled management team. This result confirms the importance of daily maintenance work, which tends to occur less often after modernisation of water paths. 相似文献