饲料中添加氯化钠对草鱼生长性能和肌肉品质的影响

Effects of dietary sodium chloride on growth and muscle quality of Ctenopharyngodon idella

为研究饲料中添加氯化钠对草鱼生长性能和肌肉品质的影响,在基础饲料中分别添加0(对照组)、10、20、30和40 g/kg氯化钠,配制成5组饲料,饲养平均体质量为(12.26±0.03) g的草鱼60 d。结果显示,添加10和20 g/kg氯化钠对草鱼增重率和饲料系数没有显著影响,但30和40 g/kg氯化钠添加组的增重率显著低于对照组,饲料系数显著升高。各组肌肉水分、粗蛋白与粗脂肪含量没有显著差异,但肌肉灰分含量随氯化钠添加量的增加而升高;与对照组相比,各氯化钠添加组的肌肉蒸失水率、离心失水率和冷冻失水率(除10 g/kg氯化钠添加组外)显著增加,10和20 g/kg氯化钠添加组的肌肉总游离氨基酸含量显著升高,20、30和40 g/kg氯化钠添加组的肌肉游离谷氨酸、天冬氨酸含量显著降低;各氯化钠添加组的肌肉硬度及30、40 g/kg氯化钠添加组的肌肉咀嚼性均显著低于对照组,而肌肉弹性和回复性无显著差异;在肠道组织学方面,30和40 g/kg氯化钠添加组的绒毛高度和绒毛宽度较对照组显著降低,各氯化钠添加组的肌层厚度显著增加。研究表明,在饲料中添加10~40 g/kg氯化钠,对草鱼幼鱼的生长性能和肌肉品质没有改善作用。

To investigate the effects of adding sodium chloride (NaCl) to diets on the growth performance and flesh quality of Ctenopharyngodon idella, five diets were prepared with NaCl addition at 0 (control diet), 10, 20, 30, 40 g/kg and fed to C. idella with an initial body weight of (12.26±0.03) g. After 60 days of feeding, 10 and 20 g/kg NaCl groups showed the similar growth to the control, while 30 and 40 g/kg NaCl groups had lower weight gain and higher feed conversion ratio than the control. No significant differences were observed in flesh proximate composition except ash among all the groups, and the ash content increased with the increasing NaCl level. The water-holding capacity was significantly decreased by the supplementation of NaCl except in thawing loss of 10 g/kg NaCl group. The addition of 10 and 20 g/kg NaCl increased the total free amino acids contents, but the supplementation of 20, 30, 40 g/kg NaCl significantly decreased the contents of free Glu and Asp in flesh. Dietary NaCl decreased the flesh hardness and the supplementation of 30 and 40 g/kg NaCl decreased the flesh chewiness, but there was no significant difference in elasticity and resilience among all the groups. In intestinal histology, the villus height and the villus width of 30 and 40 g/kg NaCl groups were significantly lower than those of the control, and the supplementation of NaCl significantly increased the muscular thickness. In conclusion, the supplementation of NaCl (10-40 g/kg) in diet did not improve the growth performance and flesh quality of C. idella.