| The research and development of new green natural feed additive is beneficial to narrow the gap of production level of swine industry between China and the developed countries in Europe and America and reduce the abuse of antibiotics in the process of pig breeding. So it could reduce drug residues and improve the quality of meat. The paper studied the effect of dietary levels of chitosan oligosaccharide on immune function and production performance of sows in late pregnancy and explored the appropriate dosage of chitosan in order to provide a theoretical basis for the application of it as a kind of feed additive.The experiment selected 35 fourth parity Landrace-York-shire sows of breeding date, pedigree, age, weight etc. in approaching. These sows were divided into five groups randomly, each group had 7 repetitions, every repetition had one sow. The control group was fed basal diet without chitosan oligosaccharide. The four experiment groups(â… , â…¡, â…¢ and â…£) were fed basal diet adding chitosan oligosaccharide. The quantity was 30, 90, 270 and 810 g/t in sequence. The test period was from 85 days after pregnancy to 7 days after farrowing. Collect the colostrum. Collect blood in the vein of ear when 7 days after farrowing. Count the stillbirth rate, birth weight, diarrhea rate and mortality of 0~7 days age of piglets. When 7 days after farrowing measure the concentration of CFSV antibody sIgA in colostrums and serum, lysozyme, IL-2 and complement C3 in serum.Results of the experiment show that:1. Adding dietary chitosan oligosaccharide had no significant effect on the stillbirth rate, birth weight, diarrhea rate and death rate of piglets(P>0.05).2. Compared with the control group, the experimental groups â… and â…¡ had no significant difference on concentration of CFSV antibody sIgA in colostrums(P>0.05), while the experimental groups â…¢ and â…£ significantly increased the concentration of CFSV antibody sIgA in colostrums(P<0.05). With chitosan oligosaccharide added levels increased, the concentration of CFSV antibody s IgA in colostrums showed significant linear and quadratic curve increased effect(P<0.01). Compared with the control group, different levels of dietary chitosan oligosaccharide significantly increased the concentration of lysozyme and CFSV antibody sIgA in serum(P<0.05). With chitosan oligosaccharide added levels increased, the concentration of lysozyme and CFSV antibody sIgA in serum showed significant linear and quadratic curve increased effect(P<0.01). According to the calculation of quadratic curve, if the chitosan oligosaccharide added level at 500~700 g/t, the concentrations of CFSV antibody s IgA in colostrums and serum and lysozyme in serum are higher. Compared with the control group, there was no significant difference between the test group â… , â…¡, â…¢ and â…£ on concentration of IL-2 and complement C3 in serum(P>0.05).Results of the experiment show that addition of chitosan oligosaccharide in diet can significantly improve the immunity of sows in late pregnancy, but had no significant effect on the production performance.The appropriate addition amount of chitosan oligosaccharide in sows diet added late pregnancy was 500~700 g/t. |
