Effects Of Coccidia Infection On Intestinal Flora Of Hu Sheep

Coccidia is one of the most common parasites in sheep and goats.When lambs infected with Eimeria,clinical manifestations are loss of appetite,weight loss,anemia,diarrhea(sometimes accompanied by blood in the stool),dehydration,and even death.Fattening sheep and adult sheep are mostly subclinical infections.Although cases of fattening sheep and adult sheep die of coccidia infection are very rare,but it can spread pathogens cause growth retardation and decline in reproductive performance.The production and quality of mutton,sheep’s milk,wool(cashmerc),sheep casings and leather are all reduced,which caused serious economic losses to the sheep industry and severely hindered the healthy development of sheep and goat breeding industry.The intestinal flora is a complex microbial community that lives in the intestinal tract of animals.It plays an important role in the intestinal barrier function,including promoting the digestion and absorption of nutrients,maintaining the intestinal physiological functions and regulating the immune function of the body.The gut microbiota in animals is normally in a dynamic equilibrium,and many factors can cause affect the intestinal flora,such as age,diet,and pathogens.Although the association between parasite infections and intestinal flora has been reported in many studies in recent years,there has been no report on the effects of coccidia infection on the intestinal flora of sheep.In this study,Illumina Miseq sequencing technology was used to investigate the effect of coccidia infection on the intestinal flora of lambs in order to provide a reference and theoretical basis for intestinal parasitic diseases in sheep.1 Investigation on the infection of intestinal parasite in barn feeding Hu sheep at different growth stages in Dengfeng CityTo investigate the infection of intestinal parasite in barn feeding Hu sheep at different growth stages,a total of 301 sheep fresh fecal samples at different growth stages were examined by using centrifugal sedimentation,Lugo’s iodine staining,Sheaher’s sugar floatation techniques and McMaster counting method to identify eggs or oocysts of the parasite.Results:The total infection rate of intestinal parasite was 62.13%(187/301).Five species of intestinal parasites were detected,coccidia and amoeba were the dminant species,with infection rates of 47.17%(142/301)and 24.25%(72/301).The infection rates of other parasites were Strongyloidesstercoralis 7.31%(22/301),Tapeworm 2.32%(7/301),mites 1.99%(6/301).Investigations on six different growth stages of lactating lambs,weaned lambs,fattening sheep,pregnant ewes,lactating ewes and breeding ramsshowed that weaning lambs has the highest parasitic infection rate 81.3%(61/75),and lactating lambs has the lowest parasitic infection rate 24%(12/50).The results of this investigation provide scientific basis for reasonable control of parasitic diseases in barn feeding Hu sheep at different growth stages.2 Effect of naturally infection of coccidia on intestinal flora of Hu sheep at different growth stagesTo investigate the effect of coccidia infection on the intestinal flora of hu sheep at different growth stages.A total of 50 Hu sheep,include lactating lambs,weaned lambs,fattening sheep,pregnant ewes and lactating ewes,were selected from a commercial sheep farm.Each age group included sheep with coccidia infection and uninfected sheep.Illumina MiSeq sequencing technology was used to investigate the dynamic changes of gut microboiota in coccidia infection and uninfected sheep.Results:We found that Firmicutes and Bacteroidetes were the predominant bacterial phyla in all samples.Compared with the uninfected group,the abundance of Firmicutes was significantly increased and Bacteroides was significantly reduced in the coccidia infection group(P<0.05).At the genus level,Ruminococcacecae_UCG-005,Christensenellaceae_R-7_group,Bacteroides and Rikenellaceae_RC9_gut_group were the four predominant genera in Hu sheep.The coccidia infection group had a higher relative abundance of Ruminococcacecae_UCG-005 and Christensenellaceae R-7_group and a lower relative abundance of Bacteroides than the uninfected group had.Coccidia infection had a greater impact on the intestinal flora of young sheep(including lactating lambs and weaned lambs),causing significant changes in the composition of the intestinal community,and the abundance of the Christensenellaceae R-7_group and Bifidobacterium significantly decreased.Age was another major factor affecting the gut microbiota of Hu sheep.In both the coccidia-infected and uninfected groups,as age increased,the diversity,richness and similarity within the group of gut microbiota increased gradually,and the gut microbiota developed into a mature community.This experiment first reported the effect of naturally infection of coccidia on the intestinal flora of Hu sheep at different growth stages,revealed the composition of intestinal flora of Hu sheep at different growth stages and the impact of coccidia infection on intestinal flora.The results suggested that coccidia infection can cause intestinal flora disturbance and decrease of some beneficial bacteria in young sheep,which provides an important reference for the study of the relationship between sheep coccidia infection and intestinal flora.3 Effect of artificial infection of coccidia on intestinal flora in weaned lambs of Hu sheepTo understand the impact of artificial coccidia infection on the intestinal flora of lambs,a large number of fresh fecal samples of sheep were collected in this experiment.1×107 oocysts were collected by saturated salt solution floating method.The sporulated oocysts were cultured and identified as 10 species of Eimeria.The mixed Eimeria oocysts were used for artificial infection tests.Ten healthy 50-day-old weaned lambs were selected and fed to 65-day-old for coccidia infection test.The lambs were divided into three groups.Group P was the coccidia infection group,three lambs were fed with 1×105 coccidia oocysts.Group DP was diclazuril treatment group,three lambs were fed with 1×105coccidia oocysts,and on the 12th diclazuril was carried out.group C was the control group and fed with an equal amount of PBS.Fecal samples were collected every two days to record coccidia oocyst excretion,weighed on days 0,7,14,21,and 28 after infection.Fecal samples were collected from the rectum for the detection of intestinal flora.Results(1)Coccidia oocysts were observed on the 7th day after coccidia infection,and the peak of oocysts excretion was reached on the 14th day,and then the oocyst discharge gradually decreased.On the 14th day after infection,the lamb lost the most weight and gradually recovered.After two days of administration,the oocysts of coccidia tended to zero in diclazuril group.Two days after the administration of the diclazuril group,the amount of coccidia oocysts tended to zero.Compared to the infected group,lambs’ weight and appetite recovered faster in the diclazuril group.(2)Coccidia infection reduces the richness and diversity of intestinal flora of lambs.Coccidia infection causes disturbance of intestinal flora and uneven distribution of flora composition.Compared with the control group,the coccidia infection group changed the composition of the intestinal community of lambs.At the phylum level,the abundance of Firmicutes and Proteobacteriawere increased in coccidia infected group,while the abundance of Bacteroidetes decreased.At the genus level,the abundance of 5-7N15 and Oscilillospira decreased,while the abundance of Clostridium increased.Compared with the infected group,diclazuril treatment significantly reduced the richness and diversity of the intestinal flora of lambs,and caused disturbance of the intestinal flora of lambs.After diclazuril treatment,the abundance of 5-7N15 and Oscilillospira decreased,while the abundance of Bacteroides,Bibersteinia and Clostridium increased.Compared with the coccidia infected group,diclazuril treatment accelerated the recovery of the intestinal community of lambs after coccidiosis infection.Compared with the coccidia infected group,diclazuril treatment accelerated the recovery of the intestinal community of lambs after coccidiosis infection.This study investigated the clinical symptoms,weight gain changes,and oocyst excretion of lambs after artificial infection with coccidia.The changes of intestinal flora of lambs after artificial infection with coccidia,and the effect of diclazuril treatment on clinical symptoms,oocyst excretion and intestinal flora of lambs were revealed.It provides theoretical basis for the prevention and control of sheep coccidiosis and the research on the relationship between coccidia infection and intestinal flora.