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91.
92.
Su Hong Ko Sugeun Go Okorie Eme Okorie Young Chul Kim Seunghyung Lee Gwang Yeol Yoo Sungchul C. Bai 《Journal of the World Aquaculture Society》2009,40(5):659-666
This study was conducted to evaluate the dietary α‐tocopherol (vitamin E) requirement in juvenile sea cucumber, Apostichopus japonicus. Sea cucumbers averaging 1.48 ± 0.07 g (mean ± SD) were randomly distributed into 18 rectangular plastic tanks of 20 L capacity in a recirculating system (20 animals per tank). Six semi‐purified experimental diets with average protein and crude lipid levels (dry matter) of 29.7 ± 0.36% and 4.39 ± 0.23% (mean ± SD), respectively were formulated to contain 0 (E4), 15 (E12), 30 (E23), 60 (E44), 120 (E77) and 600 (E378) mg α‐tocopherol/kg diet, supplied as dl‐α‐tocopheryl acetate. Diets were analyzed for α‐tocopherol content by HPLC and the α‐tocopherol levels were 4.01, 12.4, 23.1, 44.3, 77.4 and 378 mg α‐tocopherol/kg diet for E4, E12, E23, E44, E77 and E378 diets, respectively. Casein and defatted fish meal were used as the protein sources in the diets while wheat flour was the carbohydrate source. Sea cucumbers were fed each of the six experimental diets in triplicate groups. At the end of the 14‐week feeding trial, weight gain (WG), specific growth rate (SGR) and feed efficiency (FE) of sea cucumbers fed on E23, E44, E77 and E378 diets were significantly (P < 0.05) higher than those of animals fed on E4 and E12 diets. However, there were no significant differences in WG, SGR and FE among sea cucumbers fed on E23, E44, E77 and E378 diets or among those fed on E4 and E12 diets. Survival of sea cucumbers fed on E44, E77 and E378 diets were significantly higher than those of animals fed on E4, E12 and E23 diets. However, there were no significant differences among sea cucumbers fed on E4, E12 and E23 diets or among those fed on E44 and E77 diets. Whole‐body vitamin E concentration increased with α‐tocopherol content of the diets. Broken line analysis of WG showed an optimum dietary α‐tocopherol requirement of 41 mg α‐tocopherol/kg diet in sea cucumber. These results indicated that the optimum dietary α‐tocopherol requirement in sea cucumber in the form of dl‐α‐tocopheryl acetate could be higher than 23.1 mg α‐tocopherol/kg diet but lower than 44 mg α‐tocopherol/kg diet. 相似文献
93.
The hepatic biotransformation of aldrin (AD) and dieldrin (DD) was studied in liver post-mitochondrial supernatants (S-9s) from laying hens, female cattle and swine. S-9s were incubated with 0.03 nmol of AD or DD for 1 h. After 1 h, AD in the samples was almost epoxidated to DD. This formation was found with all the animal S-9s, and the highest rates occurred in pig S-9 (P < 0.01), followed by cow and hen S-9s. No reduction of DD was found with any of the S-9s. 相似文献
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95.
本文根据国外机组引进课题以及几次喷灌机设计计算的总结与研究,说明并推求出时针式喷灌机和平移式喷灌机喷灌强度和均匀度的计算公式,且提出了喷头水量分布的模拟计算方法。文章主要解决了行喷式喷灌机的喷灌强度和均匀度的计算问题。 相似文献
96.
Naoki Wada Shin'ichiro Kajiyama Joyce A. Cartagena Linyen Lin Yukio Akiyama Motoyasu Otani Go Suzuki Yasuhiko Mukai Noriaki Aoki Kiichi Fukui 《Journal of Cereal Science》2010
Endosperm texture is an important factor governing the end-product quality of cereals. The texture of wheat (Triticum aestivum L.) endosperm is controlled by puroindoline a and b genes which are both absent in rice (Oryza sativa L.). It has been reported that the endosperm texture of rice can be modified by puroindoline genes. The mechanism, however, by which puroindolines affect the ultrastructure of rice endosperm cells remains to be investigated. In this study, we observed the ultrastructure of endosperm cells and the morphology of isolated starch granules of the transgenic rice expressing the puroindoline b gene. SEM and TEM observations indicated that compound starch granules were embedded within the matrix material in non-transgenic rice, Nipponbare, whereas they were surrounded by spaces in the transgenic rice. The morphology and size of each starch granule were not different between non-transgenic and the transgenic rice. However, the transgenic rice flour showed smaller particle size, higher starch damage, and lower viscosity during gelatinization than that of non-transgenic rice. These results confirm that puroindoline b reduces the grain hardness in rice. Moreover, the results also suggest that puroindoline b functions at the surface of compound starch granules, and not on polygonal starch granules in rice endosperm. 相似文献
97.
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
98.
99.
为完善烤烟小苗移栽模式下烟苗培育技术,以育苗孔物理参数为基础,研发不同规格育苗盘,比较其对烟苗生长的影响,优选出更具有应用价值的育苗盘参数。结果表明:育苗孔上表面积较CK降低18.70%~54.41%,育苗盘孔密度较CK增加了21.21%~102.02%,育苗孔规格改变对烟苗农艺性状影响显著发生在封盘后,育苗孔容积降低幅度超过56.92%,烟苗根鲜重、根干重则显著降低,根系活力较CK显著下降,降低幅度达10.17%,叶片MDA含量明显增加,较CK高出146.44%,抗逆性降低。故小苗移栽模式下,在CK基础上,将育苗孔容积减小(幅度小于56.92%)、育苗盘孔密度增加(幅度小于77.78%)是可行的;结合育苗成本,建议在可烟区推广应用上孔径:2.41~2.54cm×2.18~2.35cm、下孔径:1.5cm×1.5cm、孔深: 4cm、孔密度:315~352孔/盘的育苗盘(长×宽:60cm×40cm)。 相似文献
100.