Aquaculture Research Unit, School of Agricultural and Environmental Sciences, Faculty of Science and Agriculture, University of Limpopo (Turfloop Campus), Private Bag X1106, Sovenga, 0727, South Africa.
Fish Physiol Biochem. 2019 Aug;45(4):1309-1320. doi: 10.1007/s10695-019-00652-3. Epub 2019 May 14.
An experiment was carried out to assess the effect of replacing fishmeal with mopane worm meal in the diet of Clarias gariepinus. Juvenile C. gariepinus weighing 67.04 ± 3 g were stocked in 15 rectangular concrete tanks connected to a recirculating system. Five diets denoted D1, D2, D3, D4 and D5 were formulated to replace fishmeal with mopane worm meal at 0, 10, 20, 40 and 60%. Triplicate groups of C. gariepinus were randomly assigned to each diet at a stocking density of 100 fish per tank. The fish were fed to apparent satiation twice daily for 51 days. All growth performance indices declined with higher mopane worm inclusion levels. Specific growth rate (SGR) declined from 1.85%/day in the control diet to 1.43%/day in diet 5. Protein efficiency ratio (PER) also declined from 25.27% in the control diet to 19.30% in diet 5. Apparent digestibility coefficient (ADC) followed a similar pattern declining from 92.2% in the control diet to 87.1% in diet 5. Both amylase and protease activity in the stomach increased with higher mopane worm inclusion levels. Despite the increased enzyme activity in the stomach, SGR declined. The decline in SGR was attributed to high acid detergent fibre (ADF 58.4 g/kg) and chitin in the mopane worm diets. Lipase and chitinase did not show any discernible pattern with high mopane worm inclusion levels in the stomach. In the intestines, protease, lipase and chitinase did not show any discernible pattern with high mopane worm inclusion levels. Consequently, the relationship between SGR and all these enzymes was weak. However, amylase activity declined with higher mopane worm inclusion levels in the intestines, and this resulted in decreased SGR (r = 0.6722). The negative effects of mopane worm meal were further confirmed by the increase in liver degradation scores at high mopane worm inclusion levels. The liver degradation score increased from 1.12 in the control to 2.46 in diet 5.
进行了一项实验，以评估在蓝圆鲹的饮食中用斑蝥虫粉替代鱼粉的效果。体重为 67.04 ± 3 g 的幼年蓝圆鲹被放养在 15 个连接到再循环系统的长方形混凝土池中。配制了五种饲料，分别表示为 D1、D2、D3、D4 和 D5，它们分别用 0、10、20、40 和 60%的斑蝥虫粉替代鱼粉。将三组蓝圆鲹随机分配到每个饲料组中，每个水箱的放养密度为 100 条鱼。鱼每天被喂食两次，直到吃饱，持续 51 天。随着斑蝥虫含量的增加，所有生长性能指标都有所下降。特定生长率（SGR）从对照组的 1.85%/天下降到 5 号饲料组的 1.43%/天。蛋白质效率比（PER）也从对照组的 25.27%下降到 5 号饲料组的 19.30%。表观消化系数（ADC）也呈现出类似的模式，从对照组的 92.2%下降到 5 号饲料组的 87.1%。随着斑蝥虫含量的增加，胃中的淀粉酶和蛋白酶活性都增加了。尽管胃中的酶活性增加，但 SGR 仍下降。SGR 的下降归因于斑蝥虫饲料中高的酸性洗涤剂纤维（ADF 58.4 g/kg）和几丁质。脂肪酶和几丁质酶在胃中随着斑蝥虫含量的增加没有表现出任何明显的模式。在肠道中，蛋白酶、脂肪酶和几丁质酶随着斑蝥虫含量的增加没有表现出任何明显的模式。因此，SGR 与所有这些酶之间的关系很弱。然而，肠道中淀粉酶活性随着斑蝥虫含量的增加而下降，这导致 SGR 下降（r=0.6722）。在高斑蝥虫含量水平下，肝降解评分的增加进一步证实了斑蝥虫粉的负面影响。肝降解评分从对照组的 1.12 增加到 5 号饲料组的 2.46。
