| The study aims to investigate the effect of fecal fluid transplantation on intestinal flora structure,brain neurotransmitter and feather pecking（FP）behavior of Muscovy ducks.A total of4-month-old adult ducks were selected,including 12 Muscovy ducks without FP behavior as donors and 48 Muscovy ducks with FP behavior were as recipients（12 were as PBS fluid transplant recipients and 36 were as fecal fluid transplant recipients）.The 36 FP Muscovy duck were divided into three trial groups:trial group 50,trial group 100and trial group 150.The three trial groups were received transplant fluids with the following concentrations:1:50,1:100 and 1:150,respectively;another 12 FP ducks were used as the control group（CON1、CON2）,transplanted with PBS.The trial period was 30d,with a transplant capacity of 50 ml,and multiple cameras were installed to record the feather pecking behavior.After the trial finished,11 sorts of tissue samples involving heart,liver,spleen,lung,kidney,pancreas,stomach,stomach,cerebrum,cerebellum and optic colliculus were collected for running quantitative PCR of SLC12A9 and GNG2 genes,and tissue expressive differential analysis was conduced;Brain tissue was collected to detect neurotransmitter content and FP behavior of Muscovy ducks was detected by video recording system.The results were as follows:Trial 1:Analysis of the differential expression of SLC12A9 and GNG2 genes in different tissues between normal ducks and FP ducks.（1）The results showed that the SLC12A9 gene had the highest m RNA expression in the duck heart tissue,and the lowest m RNA expression in the stomach（P<0.05）,The GNG2 gene had the highest m RNA expression in the cerebellum,followed by the optic colliculus,which was significantly higher than the other tissues,with the lowest m RNA expression in the stomach.SLC12A9 and GNG2 genes were expressed in the brain tissues of normal and FP ducks,and SLC12A9 had the highest m RNA expression in group 3 of normal ducks,and GNG2 had the highest m RNA expression in group 3.Suggesting that SLC12A9 gene may be negatively associated with Muscovy duck’s FP behavior,whereas GNG2 gene may positively affect duck’s FP behavior.Trial 2:Effect of fecal fluid transplantation on cecal microbiota structure and FP behavior of Muscovy ducks.（2）FP behavior analysis showed that the total number,total time and maximum time of FP behavior displayed the following changes after fecal fluid transplantation:the total FP number and total FP number of FP ducks in trial group 150were not significantly different,and the total number,total time and maximum time of FP in trial group 50and trial group 100after fecal fluid transplantation were significantly decreased.Cecal microbiota sequencing results indicated:significant differences were deteced inαdiversity andβdiversity among all the groups.βdiversity analysis showed that Firmicutes and Clostridium were more abundant than that in the trial group 150compared to the control group.There were 722 OTUS in the three trial groups,14unique OTUS in trial group 50,45 unique OTUS in trial group 100and 32 unique OTUS in trial group 150.The structural analysis of cecum microbiota showed that the dominant phyla of each group was Bacteroidetes and Firmicutes,and the proportion of trial group 100and normal group containing anaerobic bacteria was similar at the genus level after fecal fluid transplantation.Transplantation concentrations with 1:50 and 1:100 may alleviate the FP behavior of Muscovy ducks to some extent,and change the content of butyrate,Clostridium and anaerobic bacteria.However,whether these changes are related to the alleviation of FP behavior or not need the further studies.Trial 3:Effect of fecal fluid transplantation on neurotransmitter and FP behavior of Muscovy duck.（3）In this study,brain neurotransmitters were determined by high-performance liquid chromatography（LC/MS）,including dopamine（DA）,serotonin（5-HT）,5-hydroxytryptophan（5-HTP）.The results indicated that no DA was not detected,and 5-HT was not detected in individual brain tissue samples,a small amount of 5-HT was detected in most of samples The reason for this may be due to the low amount of this neurotransmitter or metabolites in the brain.The comparative analysis of the results showed that the 5-HT content of the normal group was0.0097μg/g,lower than the control group and the three trial groups,the 5-HT content of the trial group 100was 0.0202μg/g,the 5-HT content of trial group 50was 0.0115μg/g,the 5-HT content of the trial group 150was 0.019μg/g,and the 5-HT content of the control group 0.9922μg/g.The differences between the control group and the three trial groups may be related to the fecal fluid transplantation.Meanwhile,the 5-HTP content of the control group was higher than the normal group and the three trial groups,while the brain 5-HTP content was higher than the normal group,among which the 5-HTP level of the trial group 100was the closest to that of the normal group.The results showed that fecal fluid transplantation could change the stucture of cecal micriflora and content of neurotransmitters and metabolites in brain of Muscovy ducks,thus alleviate the FP behavior of Muscovy duck to certain extent.The content of 5-HT and 5-HTP in brain of Muscovy duck were related to the degree of FP behavior. |
