亚洲大片一区二区三区跳转-水多多导航凹凸福利在线-偷拍55位美女撒尿BBB毛洗澡-黑人一级综合一区二区-在线播放中文字幕日韩-色yy香蕉一区二区三区-久久精品国产亚洲av麻豆不卡-裸体国模少妇精品视频-小骚货操我啊h无码视频

水產(chǎn)前沿網(wǎng) | 網(wǎng)聚全球水產(chǎn)華人

標(biāo)題: 生物絮團(tuán)資料（英文）！需要請(qǐng)進(jìn)。 [打印本頁(yè)]

作者: cjlittlepig 時(shí)間: 2012-7-23 15:56
標(biāo)題: 生物絮團(tuán)資料（英文）！需要請(qǐng)進(jìn)。
只為共享學(xué)習(xí)資料而來(lái)！{:soso_e173:}

Feeding with microbial flocs by tilapia in minimal discharge bio-flocs technology ponds

Abstract The uptake of microbial flocs by tilapia was evaluated. Fish (tilapia Mozambique, 107 g) were stocked in 1 m3 tanks filled with water from a limited exchange intensive tilapia producing pond (bio-floc technology, BFT system). Tagged ammonium nitrogen (15NH4(SO4)2) and starch to ensure incorporation of the 15N into the bio-flocs, were added. Fish were held in the tanks for ca 2 weeks, not fed during a week period, when the only source of feed was microbial flocs. Floc volume, total suspended solids, as well as total carbon and nitrogen in suspension were monitored.
The floc plug in settling cones contained 1.4% as dry matter.
Feed uptake, evaluated through the decrease with time in respect to 4 independently determined parameters, namely floc
volume, TSS, C and N in suspension, was found to be 10.3±1.0 g kg fish−1 day−1, averaged for the computed values for these parameters However, this preliminary evaluation was based on the assumption that fish harvesting is the only mechanism affecting bio-flocs mass, neglecting biodegradation and production of flocs. Gross daily uptake of nitrogen as determined using 15N uptake data was 0.25 gN kg−1 (1.6 g protein), equivalent to the daily uptake of 6.2 g kg−1 of dry bio-flocs, 60% of that computed by the simplified mass balance approach. This difference may be attributed to microbial degradation of the bio-flocs.
Even the lower flux as evaluated through 15N uptake, constituted, in the specific case studied, almost 50% of conventional feed ration。