Relative Bioavaility Of Nano Vitamin A In Broiler Chickens

An experiment was conducted to research the relative bio-value of nano VA on growth performance,immunity indexe,calcium,phosphorus and ash conten and VA concentrations in liver,kidney and serum of broiler from 1 to 42 days of age and to provide the retical basis for the choice of nano VA in actual production.By using a single factor completely randomized design, three hundred one-day-old AA broilers were randomly divided into 10 groups with 5 replicates in each group a 6 broilers in each replicate. Ordinary VA and nano VA were used to provide750,1500,2250,3000,3750 IU/kg activity in a nutritionally completed corn-soybean meal diet. The experiment phase was divided into 1~21 d and 22~42 d.The results as follow:(1)At 1~21 d,feed/gain(F/G),thymus index(TI),spleen index(SI),fabricius index(FI) of broilers from 1 to 21 days of age were all significantly affected by ordinary VA levels(P<0.05).Dietary nano VA levels significantly affected F/G,SI and FI(P<0.05).The differences between average daily weight gain(ADG),body weight(BG) and average daily feed intake(ADFI) were not significantly affected by VA and nano VA(P>0.05).The bioavailability values of nano VA,for F/G,BG,ADG SI,FI,were repectively 0.9575,1.8155,1.8577,1.2432 and 0.8538 times as compared to VA in broilers from 1 to 21 days of age by slope ratio analysis and calculation.At 22~42 days,BW,ADG,F/G,TI,SI and FI of broilers were all significantly affected by VA and nano VA levels(P<0.05),but ADFI was not(P<0.05).The bioavailability values of nano VA,for BW,ADG,F/G,TI and SI,were repectively 1.2436,1.4408,1.0602,1.1942 and 1.0395 times as compared to ordinary VA in broilers from 22 to 42 days of age by slope ratio analysis and calculation.(2)At 1~21d,ash percentage(AP),ash Ca percentage(CaP),liver vitamin A content(LC),renal vitamin A content(RC),serum vitamin A content(SC) of broilers were significantly affected by ordinary VA levels(P<0.05),but ash P percentage(PP) was not(P>0.05).LC,RC,SC of broilers were significantly affected by Nano VA levels(P<0.05),but AP,CaP,PP were not(P>0.05).The bioavailability values of nano VA,for LC,RC,SC and CaP,were repectively 0.6786,0.7793,0.6904 and 3.1327 times as compared to ordinary VA in broilers from 1 to 21 days of age by sope ratio analysis and calculation.At 22~42 days,ordinary VA levels significantly affected AP,LC,RC,SC of broilers,nano VA levels significantly affected AP,LC,RC.CaP was not significantly affected by ordinary VA,while CaP and PP were not significantly affected by nano VA.The bioavailability values of nano VA,for LC,RC,SC and AP,were repectively 1.0148,1.1444,1.1398 and 1.4360.Conclusion:Supplementation in diet with VA or nano VA can both improve growth performance and immunity indexe,and promote the VA concentrations in liver,kidney and serum of broilers as well.The bioavailability value of nano VA for BW and ADG is 1.8155 and 1.8577 times as compared to VA in broilers from 1 to 21 days of age,while the value is 1.2436 and 1.4408 times higher than VA in broilers from 22 to 42 days of age。Overall,the bioavailability values of nano VA are genirally higher than VA.