García Teresa, Carral José M, Sáez-Royuela María, Celada Jesús D
Departamento de Producción Animal, Facultad de Veterinaria, Universidad de León, Campus de Vegazana s/n, 24071 León, Spain.
Animals (Basel). 2022 Nov 30;12(23):3362. doi: 10.3390/ani12233362.
Tench ( L.) plays a key role in the diversification of inland aquaculture, but its culture is mainly based on extensive culture systems with usually low and unpredictable yields. Rearing procedures under controlled conditions are essential to promote and consolidate tench production, and it is necessary to set up adequate feeding in early growth phases. Fish oil (FO) is currently the main source of lipids in aquafeeds, but considering the stagnation of smaller pelagic fisheries, alternative oils should be addressed. In a ninety-day experiment, the effects of partial and total replacement of FO with camelina oil (CO) on juvenile tench growth performance and whole-body composition were evaluated. Six isonitrogenous and isolipidic diets with different levels of CO were tested: 0% (control), 20%, 40%, 60%, 80%, and 100%. The survival rate was 100%, and no significant differences in growth performance (total length, weight, specific growth rate, feed conversion ratio, and biomass gain) were found. The lipid content in whole-body juveniles was significantly lower when juveniles were fed diets containing 40% and higher levels of CO than those fed the control diet whereas linolenic acid content was significantly higher. No differences in ΣSFA, ΣMUFA, ΣPUFA, Σn - 3, or Σn - 6 whole-body content were found. The nutritional indices ΣPUFA/ΣSFA and Σn - 6/Σn - 3 showed a linear increase trend with dietary CO inclusion whereas the EPA + DHA showed an opposite tendency. Compared to the control diet, EPA + DHA content (g kg) was significantly lower in juvenile tench fed a 100% CO diet, and Σn - 6/Σn - 3 was significantly higher in juvenile tench fed 80% and 100% CO diets. Overall, the results indicate that the total replacement of FO with CO in diets is feasible without negative effects on growth performance whereas the nutritional quality of juvenile tench was unaffected with a maximum replacement of 80%.
丁鱥在淡水养殖多样化中起着关键作用，但其养殖主要基于粗放养殖系统，产量通常较低且不可预测。在可控条件下的养殖程序对于促进和巩固丁鱥生产至关重要，并且在早期生长阶段建立适当的投喂是必要的。鱼油（FO）目前是水产饲料中脂质的主要来源，但考虑到小型中上层渔业的停滞，应寻求替代油源。在一项为期90天的实验中，评估了用亚麻荠油（CO）部分和完全替代FO对丁鱥幼鱼生长性能和鱼体组成的影响。测试了六种不同CO水平的等氮等脂饲料：0%（对照）、20%、40%、60%、80%和100%。存活率为100%，在生长性能（全长、体重、特定生长率、饲料转化率和生物量增加）方面未发现显著差异。当幼鱼投喂含40%及更高水平CO的饲料时，鱼体幼鱼的脂质含量显著低于投喂对照饲料的幼鱼，而亚麻酸含量显著更高。在鱼体总饱和脂肪酸（ΣSFA）、总单不饱和脂肪酸（ΣMUFA）、总多不饱和脂肪酸（ΣPUFA）、总n - 3或总n - 6含量方面未发现差异。营养指标ΣPUFA/ΣSFA和Σn - 6/Σn - 3随着饲料中CO添加量呈线性增加趋势，而二十碳五烯酸（EPA）+二十二碳六烯酸（DHA）则呈现相反趋势。与对照饲料相比，投喂100%CO饲料的丁鱥幼鱼中EPA + DHA含量（克/千克）显著降低，而投喂80%和100%CO饲料的丁鱥幼鱼中Σn - 6/Σn - 3显著更高。总体而言，结果表明饲料中用CO完全替代FO是可行的，对生长性能没有负面影响，而最大替代量为80%时，丁鱥幼鱼的营养质量不受影响。
