Effects Of Oligosaccharide From Algae On Performance,Immune Function And Cecal Microorganisms In Piglets

Weaning stress in piglets is a severe stress resulting from separation of mother and piglets,dietary changes,suboptimal digestive system function and susceptibility of intestinal function to infection.To alleviate this situation,farms usually add antibiotics to the feed.However,incorrect use of antibiotics can cause problems such as bacterial resistance,drug residues and food safety,which can affect people’s health.Currently,the common alternative antibiotic products in production are microecological agents,acidifiers,enzymes and antimicrobial peptides.Seaweed oligosaccharide is a natural plant extract that can be used as an alternative to antibiotics with the advantages of wide source,low cost and without any toxic side effects,and is significantly used in production.In this study,the effects of different doses of seaweed oligosaccharides on the production performance,immune function and cecum microflora of weaned piglets were investigated by adding different doses of seaweed oligosaccharides to the feed.In this experiment,300 weaned ternary crossbred commercial piglets at 28 days of age with basically the same weight and health were randomly divided into 5 treatments with 6replicates each and 10 piglets in each replicate.The control group（Control）piglets were fed the basal diet,and the test 2（OSA200）,3（OSA400）,4（OSA600）and 5（OSA800）groups were supplemented with 200,400,600 and 800 mg/kg of Oligosaccharide from Algae respectively on top of the basal diet of the control group.The results showed that:（1）the addition of Oligosaccharide from Algae to the piglets’ diets did not improve daily weight gain,feed-to-weight ratio and immune organ indices（liver index,lung index,spleen index and kidney index）（P > 0.05）,but increased feed intake and slaughter rate（P < 0.05）,and improved the piglets’ response to conventional nutrients（OM,CP,CHO）,GE,essential（P <0.05）,increase the apparent utilization of conventional nutrients（OM,CP,CHO）,GE,essential amino acids（lysine,leucine,isoleucine,threonine,valine,TEAA）and non-essential amino acids（aspartic acid,serine,proline,cystine,TNEAA）,increase BV,NPU and ADE values and DM apparent utilization（P < 0.05）.（2）Addition of The addition of Oligosaccharide from Algae in piglet diets can increase the activities of jejunal lactase,sucrase and maltase,to piglet diets increased T-SOD（P < 0.05）and GSH-Px activity（P <0.01）,decreased MDA（P < 0.05）,increased serum triglyceride,total cholesterol and glucose（P < 0.05）,increased serum immunoglobulin A and immunoglobulin M（P < 0.01）,decreased interleukin 1 β and interleukin 6,and increased interleukin 10（P < 0.05）;and with the increase of Oligosaccharide from Algae,immunoglobulin A and immunoglobulin M showed linear or quadratic increase（P < 0.01）,and interleukin 10 showed linear or quadratic increase（P < 0.05）,without affecting immunoglobulin G（P > 0.05）.（3）The addition of Addition of The addition of Oligosaccharide from Algae in piglet diets can increase the activities of jejunal lactase,in piglet diets can increase the activities of jejunal lactase,sucrase and maltase,reduce the concentrations of trefoil factor family 3 and histamine in the jejunum,increase the concentrations of secreted immunoglobulin A and transforming growth factor alpha in the jejunum,and can increase the abundance of Firmicutes at the phylum level,decreased the abundance of Proteobacteria,Actinobacteria and Archaea at the phylum level;and increased the abundance of Lactobacillus,Clostridium and Streptococcus at the genus level,and decreased the abundance of Escherichia,Prevotella and Pseudo-Prevotella abundance.This experiment proved that the addition of Oligosaccharide from Algae in feeds could improve feed intake and slaughter performance of piglets,increase antioxidant capacity and immunity of piglets,improve biochemical metabolism,increase nutrient and energy utilization efficiency,reduce the abundance of some pathogenic microflora in piglets’ intestinal tract,increase the abundance of beneficial bacteria,and improve the intestinal microecological balance.Under the conditions of this experiment,the appropriate amount of Oligosaccharide from Algae should be added at 600-800 mg/kg.