Evaluation of curcumin and copper acetate against Salmonella Typhimurium infection,intestinal permeability,and cecal microbiota composition in broiler chickens

Background:Interest in the use of natural feed additives as an alternative to antimicrobials in the poultry industry has increased in recent years because of the risk of bacterial resistance.One of the most studied groups are polyphenolic compounds,given their advantages over other types of additives and their easy potentiation of effects when complexes are formed with metal ions.Therefore,the objective of the present study was to evaluate the impact of dietary supplementation of copper acetate(CA),curcumin(CR),and their combination(CA-CR)against Salmonella Typhimurium colonization,intestinal permeability,and cecal microbiota composition in broiler chickens through a laboratory Salmonella infection model.S.Typhimurium recovery was determined on day 10 post-challenge by isolating Salmonella in homogenates of the right cecal tonsil(12 chickens per group)on Xylose Lysine Tergitol-4(XLT-4)with novobiocin and nalidixic acid.Intestinal integrity was indirectly determined by the fluorometric measurement of fluorescein isothiocyanate dextran(FITC-d)in serum samples from blood obtained on d 10 post-S.Typhimurium challenge.Finally,microbiota analysis was performed using the content of the left caecal tonsil of 5 chickens per group by sequencing V4 region of 16S rRNA gene.Results:The results showed that in two independent studies,all experimental treatments were able to significantly reduce the S.Typhimurium colonization in cecal tonsils(CT,P<0.0001)compared to the positive control(PC)group.However,only CA-CR was the most effective treatment in reducing S.Typhimurium counts in both independent studies.Furthermore,the serum fluorescein isothiocyanate dextran(FITC-d)concentration in chickens treated with CR was significantly lower when compared to PC(P=0.0084),which is related to a decrease in intestinal permeability and therefore intestinal integrity.The effect of dietary treatments in reducing Salmonella was further supported by the analysis of 16S rRNA gene sequences using Linear discriminant analysis effect size(LEfSe)since Salmonella was significantly enriched in PC group(LDA score>2.0 and P<0.05)compared to other groups.In addition,Coprobacillus,Eubacterium,and Clostridium were significantly higher in the PC group compared to other treatment groups.On the contrary,Fecalibacterium and Enterococcus in CR,unknown genus of Erysipelotrichaceae at CA-CR,and unknown genus of Lachnospiraceae at CA were significantly more abundant respectively.Conclusions:CR treatment was the most effective treatment to reduce S.Typhimurium intestinal colonization and maintain better intestinal homeostasis which might be achieved through modulation of cecal microbiota.

Short-term Chronic Intermittent Hypobaric Hypoxia Alters Gut Microbiota Composition in Rats

Chronic intermittent hypobaric hypoxia (CIHH) is a treatment of moderate hypoxia that simulates high altitude interrupted by normoxia. Growing evidence shows that CIHH has multiple beneficial effects on

Diverse microbiota in palatal radicular groove analyzed by Illumina sequencing:Four case reports

BACKGROUND A palatal radicular groove is an unusual developmental deformity of the tooth,which may serve as a channel linking the periodontal and periapical inflammation,and yet no literature could be obtained analyzing microbiota within the palatal radicular grooves.CASE SUMMARY Four patients diagnosed with palatal radicular groove and concomitant periodontal-endodontic deformity in permanent maxillary lateral incisors were enrolled in this work.Twelve bacterial samples from 4 patients were collected from different parts of the palatal radicular groove during intentional replantation surgery.Illumina sequencing was performed to analyze the taxonomical composition and microbiome structure inside the palatal grooves,and 1162 operational taxonomic units were obtained.The phyla of Firmicutes and Proteobacteria predominated in most of the samples.An unknown genus from the Bacillaceae family,Lactococcus,and Porphyromonas were the most abundant genera identified.There was no difference in the microbiota richness and diversity in three sections of the groove.CONCLUSION The unique ecological niches inside the palatal grooves harbored bacterial communities that shared some component features of both the endodontic and periodontal infections.The existence of palatal groove may play an interaction bridge between the root apex and tooth cervix and thus impair the outcome of traditional therapeutic methods such as root canal treatment and periodontal management.

Understanding the effects of intramuscular injection and feed withdrawal on Salmonella Typhimurium shedding and gut microbiota in pullets

Background:Gut microbiota plays a key role in health,immunity,digestion,and production in layers.Factors such as environment,diet,diseases,stress,and flock management significantly affect gut microbiota;however,it is not known how potential stressors such as intramuscular injections or feed withdrawal alter the composition of gut microbiota that result in increased the shedding level of foodborne pathogens.In the current study,the effects of intramuscular corticosterone injection and feed withdrawal were evaluated to understand their role in Salmonella Typhimurium shedding and changes in the composition of gut microbiota in layers.Results:Salmonella shedding was observed for 8 weeks post-infection.There was a significant increase in Salmonella Typhimurium count after intramuscular injection and feed withdrawal.The Salmonella infected and the negative control groups showed significant differences in the abundance of different genera in gut microbiota at week 1 and up to week 7 post infection.The infected group showed a significant reduction in alpha diversity of gut microbiota.Firmicutes reduced significantly(P<0.05)after intramuscular injection,while the feed withdrawal groups did not cause any significant changes in Proteobacteria-Firmicutes ratio.Furthermore,intramuscular injection resulted in a significant change in alpha diversity of gut microbiota.Conclusions:Exposure of chicks to relatively low dose of Salmonella Typhimurium can lead to persistent shedding in pullets.The Salmonella Typhimurium infection disrupted the gut microbiota composition immediately after infection.The potential stress of intramuscular injection and feed withdrawal significantly increased the Salmonella Typhimurium count in faeces.The intramuscular injection also resulted in a significant alteration of the Proteobacteria-Firmicutes ratio,which could increase the risk of dysbiosis.