Effect Of Source And Level Of Vitamin D₃on Performance, Eggshell Quality And Tibial Quality In Laying Hens

In order to study the nano Vitamin D3(NVD3) compared with the normal Vitamin D3(OVD3) add effect in laying hens. The experiment was conducted to investigate the effects ofdifferent vitamin D3(VD3) levels from nano vitamin D3or ordinary vitamin D3onperformance, eggshell quality, serum biochemical indexes and tibial growth of laying hens. Inorder to provide references for the laying hens diet. The experiment with2×4factorialcompletely randomized design. A total of32021-week-old healthy Nick laying hens similarbody weight were randomly allocated into eight treatments with4replications per treatmentand10hens per replication. Test laying hens fed corn-soybean meal based diet. Added in thebasal diet for1to4the OVD3100,300,900,2700IU/kg,5to8diets add100,300,900,2700IU/kg NVD3, The experiment was lasted for18weeks. The results showed as follows:（1）There were no significant interactions between VD3source and VD3level in thelaying performance, eggshell quality, serum biochemical indexes and tibial growth (P>0.05).（2）VD3source had significant effects on soft broken eggshell rate, average eggweight, tibia ash (P <0.05). The phosphorus content of tibia ash extremely significant (P<0.01), The soft broken egg shell rate, average egg weight, serum calcium and tibial strengthNVD3group significant or significantly higher than OVD3group. However the phosphoruscontent of tibial ash in NVD3group was significantly lower than VD3group (P <0.05).（3）VD3level had extremely significant effects on broken egg rate, average egg weight,tibial strength and tibial backbone heavy (P <0.01), VD3level had significant effects on serumalkaline phosphatase (ALP) and phosphorus content of tibial ash (P <0.05). With the VD3level increases, the average egg weight, serum calcium, serum total protein (TP) and tibialstrength, feed to egg ratio, soft broken egg rate, ALP activity are elevated. Eggshell thickness,eggshell strength and serum phosphorus was first elevated and then decreased trend withelevated levels of VD3. The results indicate that NVD3can replace OVD3as a VD3source indiets of laying hens, and its effect on performance and tibial quality it better than OVD3.Combining with performance, egg quality, serum biochemical indexes and tibial quality, thesuitable dietary vitamin D3level of laying hens is in the range of900to2700IU/kg.