Effects Of Potassium Diformate On The Growth Performance&Gastrointestinal Bacterial Flora In Weaning Piglets

In order to clearify the effects of potassium diformate (KDF) and antibiotics on the productive performance and health in weanning piglets,270piglets (Landrace and large white crossbreed) were selected at the age of28d (weaning day) and randomly allocated into three groups,6replicates in each group,15piglets in each replicate. Group1(negative control) were fed basal diet, without any antibiotic and acidifier, group2(positive control) were fed on the basal diet supplemented with antibotics (16.6mg/kg colistin sulfate plus45mg/kg kitasamycin and83mg/kg olaquindox), and group3(treatment group) were fed basal diet plus1%KDF. This study investigated,(1) the effects of KDF on growth performance, nutrient digestibility, behavior and diarrhea of weaned piglets;(2) the effects of KDF on the gastrointestinal bacterial flora of weanning piglets.1Effects of KDF on the growth performance and health in weannig piglets1.1Growth performanceKDF significantly improved average daily bodyweight gain (ADG), reduced feed conversion ratio (FCR) of weaned piglets compared with the basal diet group and antibiotics group (P<0.05). There were no remarkable difference in ADG, average daily feed intake and FCR between the basal diet group and the antibiotics group (P>0.05).1.2Apparent digestibilityKDF group had higher apparent digestibility of dry matter, crude protein, crude fat, crude fiber, ash, Ga and P than the basal diet group (P<0.05). KDF group had significant higher apparent digestibility of Ga and P than antibiotic group (P<0.05) at the1st week of experiment, and had higher apparent digestibility of dry matter, crude protein and ash than the antibiotic group at the3rd and4th week experiment (P<0.05). Additionaly, KDF group had higher apparent digestibility of crude fiber than antibiotics group at the4th week of experiment (P<0.05).Antibiotics group had higher apparent digestibility of crude fiber at the1st and 2nd week than basal diet group (P<0.05), and had higher apparent digestibility of crude fat than the basal diet group at the4th week of experiment (P<0.05)1.3Health and BehaviorAs compared with the basal diet group, KDF and antibiotics significantly improved the rest behavior and reduced the explore behavior (P<0.05); but did not influence other behaviors (P<0.05).KDF group had lower percentage of diarrhea, diarrhea frequency and diarrhea index than the basal diet group (P<0.05).2Effects of KDF on gastrointestinal bacterial flora of weanning piglets2.1Quantitative analysis of Lactobacills and Enterobacteria in gastric gutAt the1st week of experiment, the copies of Enterobacteria in jujunum, caecum and rectum in KDF and antibiotic groups were significant lower than that of basal diet group (P<0.05), further the copies of Lactobacilli in jejunum and rectum, and the number of total bacteria in rectum were lower in the antibiotic group than the basal diet group (P<0.05). At the2nd week, antibiotics remarkably reduced the copies of total bacteria and Lactobacilli in ileum and caecum, and Enterobacteria in rectum (P <0.05), however, KDF significantly increased the copies of Lactobacilli in ileum and reduced the copies of Enterobacteria in rectum (P<0.05). Additionaly, the copies of lactobacilli in ileum and caecum of antibiotics group were significant lower than KDF group (P<0.05). At the5th week, KDF significantly increased the copies of total bacteria and Lactobacilli in stomach than the other two groups (P<0.05), both KDF and antibiotics reduced the copies of Lactobacilli in jejunum (P<0.05).2.2Bacterial community in gastric gutDuring the5weeks of experiment, the number of DGGE band and Shannon index of bacterial flora in the stomach, jejunum and ileum were no differene among the three groups. The number of DGGE band and Shannon index of caecum bacterial flora in basal diet group was significant higher than antibiotic group and KDF group (P<0.05) at the1st and5th week after weanning. At the2nd week after weaning, the number of DGGE band and Shannon index of caecum bacterial flora in basal diet group was significant higher than antibiotic group, but no statistic differ from the KDF group. The similarity incidences of the DGGE profiles of bacterial flora in gastrointestinal content showed that:in stomach, KDF treatment shared80%similarity with antibiotic treatment at the1st week after weaning, however the three groups shared70%and50%similarity at the2nd and5th week after weaning respectively. In jejunum, the3group shared87%and40%similarity at the1st and2nd week after weaning respectively, the basal diet group and KDF group shared85%similarity at the5th week after weaning. In ileum, KDF treatment shared88%and55%similarity with antibiotic treatment at the1st and2nd week after weaning respectively, however the three groups shared80%similarity at the5th week after weaning. In caecum, the three groups shared58%similarity at the1st week after weaning, the antibiotic group and KDF group shared92%similarity at the2nd and5th week after weaning. In rectum, the three group shared85%and70%similarity at the1st and4th week after weaning respectively, the basal diet group and antibiotic group shared70%similarity at the2nd week after weaning, but the antibiotic group and KDF group shared80%and70%similarity at the3rd and5th week after weaning respectively.Above data suggest,(1) KDF could improve the feed conversion efficiency, growth performance and health condition in weaning piglet.(2) KDF could decrease the number of Enterobacteria in jejunum, ileum, caecum and rectum, but without influence the number of Lactobacilli in gastrointestinal gut of weaning piglets.