Effects Of Dietary Fiber Levels On Production Performance,Nutrient Utilization And Cecal Microflora In Geese

The effects of dietary fiber levels on production performance,nutrient utilization,and cecal microflora in geese were investigated in this study,in order to clarify the dependence of geese on the crude fiber.A total of 468 1-day-old healthy male Yangzhou goslings with similar body weight were randomly divided into 3 groups with 6 replicates per group and 26 geese per replicate.The geese were then raised for 70 days on diets with a dietary fiber level of 2.5%(Group ?),6.1%(Group ?),or 4.3%for days 1?28 and 6.1%for days 29?70(Group II).The indicators of growth performance,slaughter performance,nutrient utilization,cecal microflora etc were studied.The results were shown as follows:(1)The geese in Group I had lower body weight at days 28,35,42,49,56,63,and 70,lower average daily feed intake during days 1?28,29?70,and 1?70,and higher ratio of feed to gain during days 29?70 and 1?70 compared with those in Groups ? and ?(P<0.05 for each comparison),there was no significant difference among the groups ? and ?(P>0.05).There was no significant difference among the groups in average daily feed intake during days 1?28,29?70,and 1-70(P>0.05 for each comparison).(2)The geese in Group I had lower body length,keel length,and shank circumference at day 70 compared with those in Groups ? and ?(P<0.05 for each comparison),there was no significant difference among the groups ? and ?(P>0.05).There was no significant difference among the groups in the shank length,breast width,or breast depth(P>0.05 for each comparison).(3)The geese in Group I had lower slaughter yield,semi-eviscerated carcass yield,eviscerated carcass yield,and breast yield at day 70 compared with those in Groups ? and ?(P<0.05 for each comparison),there was no significant difference among the groups ? and ?(P>0.05).The dietary fiber levels had no significant effects on the thigh yield or abdominal fat yield(P>0.05).(4)The geese in Group I had lower relative weights of the heart,gizzard,proventriculus,duodenum,jejunum,ileum,and cecum at day 70 compared with those in Groups ? and ?(P<0.05 for each comparison),there was no significant difference among the groups ? and ?(P>0.05).The dietary fiber levels had no significant effects on the relative weight of the liver,spleen,bursa,thymus,or rectum(P>0.05).(5)The geese in Group I had higher serum levels of alanine transaminase,blood urea nitrogen,and uric acid,lower levels of glucose and high-density lipoprotein at day 70 compared with those in Groups ? and ?(P<0.05 for each comparison),there was no significant difference among the groups ? and ?(P>0.05).In addition,the geese in Group ? had a higher serum aspartate aminotransferase level compared with those in Group II(P<0.05).(6)The geese in Group I exhibited significantly lower utilization of energy and crude protein compared with the geese in Groups ? and ?(P<0.05 for each comparison),there was no significant difference among the groups ? and ?(P>0.05).There was no significant difference in the utilization of crude fat,crude fiber,neutral detergent fiber,or acid detergent fiber among the groups(P>0.05).(7)The geese in Group ? had lower Chaol index,Shannon index,and ACE index,higher OTUs and Simpson index at day 28 compared with these in groups ? and ?.The geese in Group ? had lower relative abundance of Bacteroidetes,Firmicutes,Bacteroides,Megamonas,Paraprevotella,and Clostridium XlVa,higher relative abundance of Proteobacteria compared with these in groups ? and ?.In addition,the similarity of cecal microflora between Group ?and Group ?,between Group ? and Group ? were smaller.(8)The geese in Group I had lower OTUs,Chaol index,Shannon index,and ACE index,higher Simpson index at day 70 compared with these in groups ? and ?.The geese in Group ?had lower relative abundance of Bacteroidetes,Firmicutes,Bacteroides,and Paraprevotella,higher relative abundance of Proteobacteria compared with these in groups ? and ?.In addition,the similarity of cecal microflora between Group I and Group ?,between Group ? and Group ?were smaller.In conclusion,the low-fiber diet(2.5%)had negative effects on growth performance,slaughter performance,serum biochemical parameters and nutritent utilization in geese.Low-fiber diet decreased diversity of microflora,and the relative abundance of Bacteroidetes,Firrmicutes,Bacteroidia and Paraprevotella,increased the relative abundance of Proteobacteria in cecum of geese.