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1.
ABSTRACT: To clarify the quantitative changes in the transport of orally intubated protein into the blood circulation as macromolecules in development, immunoglobulin Y (IgY) extracted from chicken eggs was administered orally to juvenile Japanese eel, Anguilla japonica . For the first experiment, which was performed before the commencement of artificial feeding, the oral delivery of 2.0 μg/0.1 g bodyweight of IgY resulted in a rapid increase in plasma IgY to a maximum of 2.30 μg/mL. However, the transport of IgY into the blood decreased significantly in the experiments that followed, which were performed after 12, 25 and 42 days. During this period, bodyweight increased approximately by a factor of eight, and rapid growth of the stomach was observed histologically. Possible contributions for the development of the alimentary canal to the diminishment of intestinal protein assimilation are discussed. 相似文献
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南美白对虾淡水养殖试验报告 总被引:3,自引:0,他引:3
采取人工调兑淡水盐度,定点投喂颗粒饲料,调节水质及病害预防措施,在667m^2淡水池塘中养殖南美白对虾,经107天的饲养管理,共产南美白对虾160.2kg,平均体长达13.5cm/尾,体重20g/尾,成活率达到80.1%,共获利润5732.5元,投入产出比1:2.47。 相似文献
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P. Laffaille A. Acou J. Guillouët B. Mounaix A. Legault 《Ecology of Freshwater Fish》2006,15(4):583-588
Abstract – Changes in the numbers and size-class structure of European silver eels, Anguilla anguilla , in the River Frémur (France) were examined over a 9-year period after installation of downstream eel passes. The number of silver eels migrating downstream peaked in 1999, then decreased strongly and steadily after 2000, reaching relatively low levels. At the same time, a gradual shift in the silver eel sex ratio from a dominance of males (size from 270 to 442 mm, age from 3 to 6 years) to females (size from 366 to 1112 mm, age from 4 to 9 years) was recorded. Possible explanations for the escapement patterns observed are environmental sex determination and the installation of eel passes on the main hydraulic engineering structures in 1992 and 1996. 相似文献
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A radioimmunoassay for llama and alpaca LH was developed using a human I125LH tracer from a commercial kit, equine LH diluted in human LH free serum as standard, and a monoclonal antibody (518B7) specific for LH but with low species specificity. A 60-min delay in the addition of the tracer and overnight incubation gave a sensitivity of 0.8 μg L−1. The intra-assay coefficient of variation was 37% at 1 μg L−1, declined to 15% at 4 pg L−1 and was below 6% for concentrations up to 32 μg L−1. The inter-assay coefficients of variation for 3 control samples were 20% (2.8 μg L−1), 16% (7.1 μg L−1) and 9.8% (19 μg L−1). In an attempt to increase sensitivity, all tubes were preincubated for 4 h at room temperature before adding the tracer, and the sample volume was increased from 50 μL to 100 μL· (in the standard curve the increased volume was compensated for by human LH free serum). With this protocol, the assay sensitivity was 0.5 μg L−1. The assay was validated clinically and demonstrated increased concentrations of LH after mating in llamas and alpacas. Furthermore, the assay was used to monitor LH responses to a single dose of GnRH in llamas (adult males and females at different ages). 相似文献
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应用铸型技术等方法研究了黄鳝排尿器官的解剖学结构。结果见到,黄鳝2条中肾管在中肾末端与所谓退化性腺(亦即膀胱)相连,并与该“退化性腺”之间存在着明显的通道关系,而“退化性腺”直接通于尿孔。此外,组织学的研究也支持了解剖学结果,并证实中肾管在“退化性腺”中存在着2种开口类型;单口型和双口型。研究结果为作者先前提出的有关黄鳝“退化性腺”是膀胱的结论提供了直接的形态学证据。 相似文献