Effects Of Different Fiber Source Diets On Growth Performance、Apparent Digestibility And Gut Microbial Composition Of Weaning Tibetan Pigs

This experiment investigated the effects of different fiber sources in diets on growth performance,nutrient digestibility,blood biochemical indexes and intestinal microbial composition of Tibetan pigs.Thirty-six healthy weaned Tibetan piglets with an initial weight of(5.32±0.61)kg were selected and randomly divided into three groups of six replicates each,with two pigs in each replicate.Each group was fed fiber-free diet(control group),diet supplemented with 5% inulin(treatment 1 group),and diet supplemented with 5% microcrystalline cellulose(treatment 2 group).The test period was 42 d,including 7 d of pretest,35 d of feeding test,and 7 d of digestion test at the same time when the feeding test was conducted to 28 d.The results showed that(1)there was no significant difference(P > 0.05)in the feed-to-weight ratio between the three groups.Compared with the control group,the average daily weight gain of treatment 1 group was not significantly different,but the average daily weight gain of treatment 2 group was significantly higher(P < 0.05),and the average daily feed intake of both treatment 1 and treatment 2 groups was significantly higher(P < 0.05).(2)There was no significant difference in nutrient digestibility of crude protein and neutral detergent fiber among the three groups(P > 0.05).Compared with the control group,there was no significant difference in nutrient digestibility of energy,dry matter and crude ash in the treatment 1 group(P > 0.05),but nutrient digestibility of crude fat and acidic detergent fiber was significantly higher(P <0.05),and there was no significant difference in nutrient digestibility of energy in the treatment 2 group(P > 0.05),but nutrient digestibility of crude fat,crude ash and acidic detergent fiber was significantly higher(P < 0.05)and nutrient digestibility of dry matter was significantly lower(P < 0.05).(3)Compared with the control group,the content of alkaline phosphatase was not significantly different in the treatment 1 group(P > 0.05),but was significantly lower in the treatment 2 group(P < 0.05),and no significant differences were found in any other indexes(P > 0.05).(4)By sequencing,it was found that at the phylum level,the relative abundance of the phylum Proteobacteria was significantly lower(P < 0.05)in the treatment 1 and treatment 2 groups compared with the control group,while the relative abundance of the phylum Spirochaetota was significantly increased(P < 0.05)in the control group,and the relative abundance of the phylum Spirochaetota in the treatment 2 group.The relative abundance of Spirochaetota was not significantly different(P > 0.05);at the genus level,the relative abundance of Escherichia＿Shigella was significantly lower(P < 0.05)in the treatment 1 and treatment 2 groups compared to the control,but the relative abundance of Phascolarctobacterium The relative abundance of Phascolarctobacterium was significantly higher in treatment 1(P< 0.05),and the relative abundance of Treponema in treatment 2 was not significantly different(P > 0.05).In conclusion,the addition of soluble fiber(inulin)and insoluble fiber(microcrystalline cellulose)to the diet can promote the growth of weaned Tibetan piglets,and can increase the relative abundance of beneficial bacteria and decrease the relative abundance of pathogenic bacteria in the digestive tract to a certain extent to maintain the health of the digestive tract.