低磷饲料中添加α-酮戊二酸对松浦镜鲤生长性能、体成分和血清生化指标的影响

EFFECTS OF α-KETOGLUTARATE SUPPLEMENTATION IN LOWPHOSPHOROUS DIETS ON GROWTH PERFORMANCE, BODY COMPOSITION AND SERUM BIOCHEMICAL INDEXES OF SONGPU MIRROR CARP

试验旨在研究低磷饲料中添加α-酮戊二酸(α-ketoglutarate,AKG)对松浦镜鲤(Cyprinus carpio Songpu)生长性能、体成分和血清生化指标的影响。选取平均体重为(6.67±0.14)g的松浦镜鲤630尾,随机分成7组,每组3个重复。分别投喂有效磷0.73%的正常磷饲料和有效磷0.47%的低磷饲料,在低磷饲料中分别添加0、0.4%、0.8%、1.2%、1.6%、2.0%(干物质含量)的AKG,配制成等氮等能饲料,试验期为8周。结果表明:低磷组饲料系数(FCR)显著高于正常磷组(P<0.05),但增重率(WGR)、特定生长率(SGR)、蛋白质效率(PER)、脏体指数(VSI)及肥满度(CF)差异不显著(P>0.05);与低磷组比,0.4%AKG组FCR显著降低(P<0.05),1.6%AKG组血清磷、白蛋白含量(ALB)显著增加(P<0.05);0.8%AKG组谷草转氨酶(AST)活性和1.20%AKG组谷丙转氨酶(ALT)活性显著高于正常磷组(P<0.05);添加不同水平AKG对血清其他指标无显著影响(P>0.05)。与正常磷组相比,低磷组粗灰分含量、骨钙含量和钙磷沉积率显著降低(P<0.05);与低磷组相比,添加不同水平AKG磷沉积率显著增加(P<0.05),0.4%AKG组,骨钙含量显著增加(P<0.05),0.8%AKG组,骨磷含量显著增加(P<0.05);低磷饲料添加AKG对其他体成分指标无显著影响(P>0.05)。由此得出,低磷饲料中添加适量的AKG可以降低FCR,提高松浦镜鲤脊椎骨钙磷含量。

To study the effects of α-ketoglutarate（AKG） supplementation in low-phosphorous diets on growth performance, body composition and serum biochemical indexes of Songpu mirror carp, triplicate groups of Songpu mirror carp（6.67±0.84） g were fed with practical diets containing available P（AP） 0.73%（normal P） and 0.47%（low-P） with graded levels of 0, 0.4%, 0.8%, 1.2%, 1.6% and 2.0% of AKG to satiation for 8 weeks, respectively. The results showed that the feed coefficient（FCR） of the low phosphorus group was significantly higher than that of the normal phosphorus group（P〈0.05）, but the weight gain rate（WGR）, specific growth rate（SGR）, protein efficiency（PER）, VSI,and CF were similar between normal P and Low-P groups（P〈0.05）. Compared with low P group, FCR of 0.4% AKG group and the levels of phosphorus and albumin（ALB） in 1.6% AKG group in normal P group were significantly increased（P〈0.05）, respectively. Compared with normal P group, ALT activity of the 0.8% AKG and AST activity of the1.6% AKG in the low P group were significantly increased, respectively（P〈0.05）. AKG had no effect on serum other indexes（P〈0.05）. Compared with the normal phosphorus group, the content of crude ash and the deposition rate of calcium and phosphorus in the low phosphorus group decreased significantly（P〈0.05）. Compared with the low phosphorus group, the phosphorus deposition rate and bone calcium content of 0.4% AKG and bone phosphorus content of0.8% AKG in normal P group increased significantly, respectively（P〈0.05）. Adding AKG in low phosphorus diet had no significant effect on other body composition indexes（P〉0.05）. Thus, the suitable supplementation of AKG in the low phosphorus diets can reduce the FCR and improve the content of calcium and phosphorus in bone of Songpu mirror carp.