Effects Of Dietary L-Carnitine And Betaine On Growth And Lipid Metabolism Of Tilapia

1 Effect of dietary L-carnitine on growth and lipid metabolism of TilapiaThe study was conducted to investigate effects of different dietary levels of L-carnitine on growth and lipid metabolism in tilapia,and study on the mechanism in tilapia's fatty liver pathological changes of L-carnitine in the feed.Seven hundred and fifty tilapias ,with mean weight (0.30±0.01) gram,were divided into five groups according to the level of dietary L-carnitine (0,50,100,150,200mg/kg) to investigate the effects on growth and lipid metabolism.The results showed that tilapia's WGR and CF improved 824.08% and 0.36%(p<0.05) ,and HIS and FRC reduced 0.15% and 0.43(p<0.05) respectively,compared with the control,when tilapia feed were added with 150mg/kg L-carnitine ; physiologically,L-carnitine decreased the level of CHOL,TG,AST,ALT and BUN,increased ALB and LDH concentration significantly.And discovered that when tilapia feed were added with 150mg/kg L-carnitine,the differences were significantly.The figure of tissue slices showed that L-carnitine improved villas length,density and the distribution uniformity of duodenum,improved the cellularity of liver cell,arranged compactly. The results of rearing indicated that it promotes tilapias growth when tilapia feed were added with 150 mg/kg L-carnitine.It also maked for lipid metabolism.2 Effect of dietary Betaine on growth and lipid metabolism of TilapiaThe study was conducted to investigate effects of different dietary levels of Betaine on growth and lipid metabolism in tilapia,and study on the mechanism in tilapia's fatty liver pathological changes of Betaine in the feed. Seven hundred and fifty tilapias ,with mean weight (0.29±0.02) gram , were divided into five groups according to the level of dietary Betaine(0,0.15%,0.3%,0.45%,0.6%) to investigate the effects on growth and lipid metabolism.The results showed that tilapia's WGR and CF improved 1157.28% and 0.13% (p<0.05),and HIS reduced 0.54% (p<0.05) respectively,compared with the control,when tilapia feed were added with 0.45% betaine;FRC reduced 0.41 (p<0.05) compared with the control, and the activities of ALT(37.50±7.78)U/L and AST(146.67±12.42) U/L were lowest in Tilapia'plasma when tilapia feed were added with 0.6% betaine. Betaine can reduced the content of CHOL(2.28±0.19)mmol/L,TG (0.33±0.19) mmol/L and BUN (1.61±0.17) mmol/L;also increased the activities of LDH (791.00±103.32) U/L and AMY(150.00±70.07) U/L, and the amount of ALB (12.3±0.98) g/L in Tilapia'plasma.Also reduced the amount of fat in liver markedly. The figure of tissue slices showed that L-carnitine improved villas length,density and the distribution uniformity of duodenum,improved the cellularity of liver cell,arranged compactly.The results of rearing indicated that it promotes tilapias growth and maked for lipid metabolism when tilapia feed were added with 0.45-0.6% betaine,it prevents and controls fatty liver pathological effectively.