Wang Shaodan, Zuo Zhiheng, Wang Qiujie, Zhou Aiguo, Wang Guiqin, Xu Guohuan, Zou Jixing
Joint Laboratory of Guangdong Province and Hong Kong Region on Marine Bioresource Conservation and Exploitation, College of Marine Sciences, South China Agricultural University, Guangzhou, China.
Guangdong Laboratory for Lingnan Modern Agriculture, South China Agricultural University, Guangzhou, China.
Water Environ Res. 2023;95(2):e10836. doi: 10.1002/wer.10836.
It is essential to increase the use of carbohydrates as an energy source and improve protein synthesis and utilization to reduce ammonia nitrogen emissions. A 60-day cultural experiment was conducted to assess the impact of resistant starch (kelp meal, Laminaria japonica) replacing starch on water quality, nitrogen and phosphorus budget and microbial community of hybrid snakehead. Approximately 1350 experimental fish (11.4 ± 0.15 g) were randomly divided into control group (C, 20% starch) and four resistant starch groups: low replacement group (LR, 15% starch), medium replacement group (MR, 10% starch), high replacement group (HR, 5% starch) and full replacement group (FR, 0% starch). The crude protein and crude fat content of hybrid snakehead fish fed with the FR diet had the most significant improvement (P < 0.05). However, resistant starch also increased the effectiveness of nitrogen and phosphorus utilization in hybrid snakeheads, which decreased the proportion of total nitrogen and total phosphorus in tail water. The minimum nitrogen and phosphorus emission rate was when the starch level was 6.1%. Denitrifying microbes including Gemmobacter, Rhodobacter, Emticicia and Bosea have become much more prevalent in group FR (P < 0.05). In general, replacing starch with resistant starch can enhance the rate at which nitrogen and phosphorus are used in feeding, lessening water pollution and altering environmental microbial composition. PRACTITIONER POINTS: Resistant starch (RS) improves whole fish nutritional content. Resistant starch improves dietary nitrogen and phosphorus utilization. Resistant starch acts as a carbon source and encourages the colonization of denitrifying bacteria in water.
增加碳水化合物作为能源的使用，并提高蛋白质合成与利用，以减少氨氮排放至关重要。进行了一项为期60天的养殖实验，以评估抗性淀粉（海带粉，海带）替代淀粉对杂交乌鳢水质、氮磷收支和微生物群落的影响。约1350尾实验鱼（11.4±0.15克）被随机分为对照组（C，20%淀粉）和四个抗性淀粉组：低替代组（LR，15%淀粉）、中替代组（MR，10%淀粉）、高替代组（HR，5%淀粉）和全替代组（FR，0%淀粉）。投喂FR日粮的杂交乌鳢鱼的粗蛋白和粗脂肪含量改善最为显著（P<0.05）。然而，抗性淀粉也提高了杂交乌鳢对氮和磷的利用效率，降低了尾水中总氮和总磷的比例。淀粉水平为6.1%时，氮磷排放率最低。包括宝石杆菌属、红杆菌属、埃姆蒂西亚菌属和博斯氏菌属在内的反硝化微生物在FR组中更为普遍（P<0.05）。总体而言，用抗性淀粉替代淀粉可提高饲料中氮和磷的利用率，减少水污染并改变环境微生物组成。从业者要点：抗性淀粉（RS）可提高全鱼营养成分。抗性淀粉可提高日粮氮磷利用率。抗性淀粉作为碳源，促进反硝化细菌在水中定殖。
