Effects of citric acid on growing performance and nutrients digestibility of allogynogenetic crucian carp

Abstract:

Two experiments were conducted to investigate the effects of adding citric acid on growing performance and digestibility of allogynogenetic crucian carp.In experiment 1,420 healthy fish with an average weight of 6.5 g,were separated randomly into 5 groups and fed with 0.0%(control),0.1%,0.2%,0.3% citric acid addition for 21 days,the growth rate was 53.4%,56.9%,59.0%,57.8%,respectively.The growth rate was significantly improved by 0.2% addition(P<0.05).In experiment 2,150 healthy fish with average weight of 45.0 g were separated randomly into 5 groups and fed the diet with 0.0%(control),0.1%,0.2%,0.3%,0.4% citric acid addition for two weeks to measure nutrients digestibility.The results showed that phosphorus(P) digestibility was significantly improved by 0.1% or 0.2% citric acid addition and dry material(DM) digestibility only by 0.2% citric acid addition(P<0.05).Adding citric acid in diet had no effect on protein digestibility.Results above showed that adding proper level of citric acid could promote the growing performance and P,DM digestibility for allogynogenetic crucian carp,and the appropriate level of citric acid addition is 0.2%.