Study On Effect Of Rare Earth-Chitosan Chelation On GH/IGF-I Axis And Mechanism Of Layers

The present study was carried out to reveal the molecular mechanis of rare earth-chitosan chelation. Four-hundred and fifty healthy laying hens of 28-week-age were randomly divided into 5 groups with 10 replicates of each, per replication was 9 layers. The control group was fed with the the corn-soybean meal basal diet, the trial groups (Group I, II, III and IV) with basal diet plus 0.05%, 0.10%, 0.15% and 0.20% rare earth-chitosan chelation, respectively. The results were shown as follows:1 Effect of the rare earth-chitosan chelation on the concentrations of related hormones in layersIn the contrast with the control group, the concentration of GH of the treatment I, II, III and IV was increased by 37.5%(P<0.01), 25.58% (P<0.01), 37.5% (P<0.01) and 43.75% (P<0.01) respectively; The concentration of IGF-1 of the treatment I, II, III and IV was increased by 34.19%(P<0.01), 43.2% (P<0.01), 38.73% (P<0.01) and 43.37% (P<0.01) respectively. The significantly increase of GH and IGF-I levels may be involved in the mechanisms of rare earth-chitosan chelation action on improving production performance of layers.2 Effect of the rare earth-chitosan chelation on the relative abundance of related gene mRNAThe level of IGF-I mRNA of the treatment I, II, III and IV was significantly higher than the control group in the liver of layers, respectively, but had no effect on the level of IGF-IR mRNA in the ovary and magnum of layers. These changes in mRNA expression of IGF-I imply a gene-mediated mechanism of the rare earth-chitosan chelation action on reproductive performance in the layers, and the IGF-IR can regulate the ovary and magnum, but the mechanism needs to be studied more.