北方须鳅室内当年养成食用鱼试验

Edible Culture of Loach Barbatula barbatula nuda in Indoor Tanks Within the Same Year

2016年5月,将3万尾北方须鳅Barbatula barbatula nuda仔鱼等量放养在玻璃暖棚内的三个水族箱(100cm×50cm×45cm)中,以曝气48h的深井水为水源,水温18℃,24h连续充气,投喂自制微颗粒饲料,培育成平均体质量1.10~1.38g、平均全长5.30~6.04cm的鱼种。再将小规格鱼种养在4个Φ800mm×850mm的圆形塑性桶内,每桶500尾;大规格鱼种养在8个同规格桶内,每桶375尾。桶内24h充气,溶氧量保持在5mg/L以上,养殖水深0.5m,水温16~19℃,每天8:00和18:00投喂鱼体质量3%左右的自制饲料,上午9:00换水2/3以上,水源同上。经114d培育,小规格的北方须鳅全长达(7.49±0.70)cm,体质量(3.09±0.86)g,增长速度达0.02g/d,成活率95.2%;大规格北方须鳅全长达(8.50±0.63)cm,体质量(4.59±1.18)g,增长速度0.03g/d,成活率达67.5%,饲料系数达1.13。两种规格的全长(L)和体质量(W)的关系式分别为W=0.0057L_T^(3.0831)(R^2=0.9273)和W=0.0058L_T^(3.0533)(R^2=0.9136),属匀速增长型。结果表明,室内人工养殖北方须鳅完全可行。

A total of 30 thousand of fry loach Barbatula barbatula nuda were reared in three aquaria of each 100 cmx 50 cm x 45 cm supplied with deep well water exposed to the sun 48 h and aerated daily in a greenhouse at the same stock density, and fed self- restraint granulated diet at water temperature of 18℃ in May of 2016. Then 2 thousand fingerlings with average total length of 5.30 6.04 cm and body weight of 1.10 - 1.38 g reared above were stocked into 4 round plastic barrels of each Ф 800 mm × 850 mm at a rate of 375 fish per barrel for the small-sized fingerlings and at a rate of 500 fish per barrel for the large-sized ones at daily water exchange rate of 2/3 of the total volume water and fed self-restraint granulated diet at 8：00 and 18：00 at feeding rate of some 3% twice a day at water temperature of 16 - 19 ~C for 114 d. It was found that the small-sized fingerlings had final total length of （7.49 ~ 0.70） cm, final body weight of （3.09 ＋ 0.86） g, with weight gain rate of 0.02 g/d and survival rate of 95.2%, while the large-sized finger- lings had final total length of （8.50 ＋ 0.63 ） cm, final body weight of （4.59~ 1.18 ） g, with weight gain rate of 0.03 g/d and survival rate of 67.5%. There was food conversion ratio of 1.13 during the culture period for both sized loach juveniles. The linear relationship between body weight （W） and total length （L） was expressed as Wsmall-=0.0057Lr3.0831 （R^2 = 0.9273 ） for the small-sized fingerlings and Wlorger=0.005 8LT3.0533 （R^2 = 0.9136 ） for the large-sized fingerlings ,with power of near 3, showing uniform growth. Thus, it is feasible for Barbatula barbatula nuda culture in an indoor tank.