A lytic bacteriophage isolate reduced Clostridium perfringens induced lesions in necrotic enteritis challenged broilers

Background Bacteriophages are viral predators of bacteria and are common in nature. Their host-specific infections against specific bacteria make them an attractive natural agent to control bacterial pathogens. Interest in the potential of bacteriophages as antibacterial agents in the production animal industries has increased. Methods A total of 18 bacteriophages were isolated from Australian commercial poultry environments, from which three highly active phages were chosen for enrichment. Sequencing libraries were prepared using a Nextera XT kit (Illumina) and sequenced on an Illumina MiSeq instrument using 2 × 300 bp paired-end chemistry. The sequence data were then assembled and aligned with a2 bacteriophage as the reference. An animal trial was performed by oral gavaging Clostridium perfringens netB containing strain EHE-NE18 to the Ross 308 broiler chickens prior inoculation with Eimeria species. The chickens were raised following the management guide for Ross 308 from d 0 to d 21 and fed with starter and grower diets met the specific breed nutrient requirements. Body weight gain and feed intake were measured on d 9 and d 21 and FCR adjusted with mortality was calculated. Results The isolated bacteriophages only had only 96.7% similarity to the most closely related, previously characterized, Clostridium bacteriophage indicated that they might represent a novel strain of bacteriophage. A “cocktail” containing the three bacteriophages was capable of lysing four known disease-inducing C. perfringens strains in vitro. Oral administration of the bacteriophages cocktail to broilers challenged with necrotic enteritis markedly alleviated intestinal necrotic lesions in the duodenum and jejunum on day 16 post-hatch. The phage treatment significantly reduced the lesion scores of birds challenged with NE (P 0.05). However, no effect on the growth performance was observed during the recorded period of days 9-21. Conclusion These findings suggest that bacteriophage treatment is a promising approach to protect intestinal health from C. perfringens induced necrotic enteritis. Further research will be required on the dosing, route of administration, and large scale validation studies to further advance this approach to pathogen control

Can a Short Food Supply Chain Create Sustainable Benefits for Small Farmers in Developing Countries? An Exploratory Study of Vietnam

A number of studies have indicated that short food supply chains could create economic, social, and environmental benefits, but most of those chains were implemented in developed countries. This research aims to find out the characteristics of short food supply chains and their benefits to small farmers in Vietnam, which is a developing country, based on the survey results from 338 small farmers in the third quarter of 2020, with the support of Stata 14 software. The results showed that the short food supply chains in the survey sample in Vietnam were characterized by two main actors: small farmers and distributors. Farmers could sell products flexibly at the local market. There was some initial evidence to prove that these chains helped to stabilize the input, output price, and revenue; formulated sustainable income; and increased the satisfaction and confidence of farmers. They eliminated gender discrimination in rural areas and improved livelihood for ethnic minorities. These chains also enhanced the mindset on green, organic, and clean production of farmers, which in turn created environmental benefits. COVID-19 has posed a negative impact on the income of farmers and made them change their production and sales method. Therefore, the research could suggest some policies to sustainably develop the short food supply chains in Vietnam in the future

Pioneering gut health improvements in piglets with phytogenic feed additives

This research investigates the effects of phytogenic feed additives (PFAs) on the growth performance, gut microbial community, and microbial metabolic functions in weaned piglets via a combined 16S rRNA gene amplicon and shotgun metagenomics approach. A controlled trial was conducted using 200 pigs to highlight the significant influence of PFAs on gut microbiota dynamics. Notably, the treatment group revealed an increased gut microbiota diversity, as measured with the Shannon and Simpson indices. The increase in diversity is accompanied by an increase in beneficial bacterial taxa, such as Roseburia, Faecalibacterium, and Prevotella, and a decline in potential pathogens like Clostridium sensu stricto 1 and Campylobacter. Shotgun sequencing at the species level confirmed these findings. This modification in microbial profile was coupled with an altered profile of microbial metabolic pathways, suggesting a reconfiguration of microbial function under PFA influence. Significant shifts in overall microbial community structure by week 8 demonstrate PFA treatment’s temporal impact. Histomorphological examination unveiled improved gut structure in PFA-treated piglets. The results of this study indicate that the use of PFAs as dietary supplements can be an effective strategy, augmenting gut microbiota diversity, reshaping microbial function, enhancing gut structure, and optimising intestinal health of weaned piglets providing valuable implications for swine production. Key points • PFAs significantly diversify the gut microbiota in weaned piglets, aiding balance. • Changes in gut structure due to PFAs indicate improved resistance to weaning stress. • PFAs show potential to ease weaning stress, offering a substitute for antibiotics in piglet diets

Survival Mechanisms of Campylobacter hepaticus Identified by Genomic Analysis and Comparative Transcriptomic Analysis of in vivo and in vitro Derived Bacteria

Chickens infected with Campylobacter jejuni or Campylobacter coli are largely asymptomatic, however, infection with the closely related species, Campylobacter hepaticus, can result in Spotty Liver Disease (SLD). C. hepaticus has been detected in the liver, bile, small intestine and caecum of SLD affected chickens. The survival and colonization mechanisms that C. hepaticus uses to colonize chickens remain unknown. In this study, we compared the genome sequences of 14 newly sequenced Australian isolates of C. hepaticus, isolates from outbreaks in the United Kingdom, and reference strains of C. jejuni and C. coli, with the aim of identifying virulence genes associated with SLD. We also carried out global comparative transcriptomic analysis between C. hepaticus recovered from the bile of SLD infected chickens and C. hepaticus grown in vitro. This revealed how the bacteria adapt to proliferate in the challenging host environment in which they are found. Additionally, biochemical experiments confirmed some in silico metabolic predictions. We found that, unlike other Campylobacter sp., C. hepaticus encodes glucose and polyhydroxybutyrate metabolism pathways. This study demonstrated the metabolic plasticity of C. hepaticus, which may contribute to survival in the competitive, nutrient and energy-limited environment of the chicken. Transcriptomic analysis indicated that gene clusters associated with glucose utilization, stress response, hydrogen metabolism, and sialic acid modification may play an important role in the pathogenicity of C. hepaticus. An understanding of the survival and virulence mechanisms that C. hepaticus uses will help to direct the development of effective intervention methods to protect birds from the debilitating effects of SLD

Bacillus amyloliquefaciens probiotics mix supplementation in a broiler leaky gut model

The supplementation of antimicrobial growth promoters (AGPs) has been banned in many countries because of the emergence of antimicrobial-resistant pathogens in poultry products and the environment. Probiotics have been broadly studied and demonstrated as a promising AGP substitute. Our study is centred on the effects of a multi-strain Bacillus-based probiotic product on broiler production performance and gut microbial profile in a dexamethasone-induced leaky gut challenge. Two hundred and fifty-six broiler chicks were hatched and randomly assigned into four groups (wheat-soybean meal basal diet (BD) = non-supplemented control (C), BD supplemented with dexamethasone in week 4 (CD), BD containing a probiotic from day one (P), and BD containing a probiotic from day one and supplemented with dexamethasone during challenge week 4 (PD)). The production performance and caecal, gizzard, jejunal lumen and jejunal mucosa swab microbiota were studied by 16S rRNA gene sequencing. The Bacillus probiotic product significantly improved production performance and altered caecal gut microbiota (p ≤ 0.05), but no significant impact on microbiota was observed in other gut sections

Microbial communities of poultry house dust, excreta and litter are partially representative of microbiota of chicken caecum and ileum

Traditional sampling methods for the study of poultry gut microbiota preclude longitudinal studies as they require euthanasia of birds for the collection of caecal and ileal contents. Some recent research has investigated alternative sampling methods to overcome this issue. The main goal of this study was to assess to what extent the microbial composition of non-invasive samples (excreta, litter and poultry dust) are representative of invasive samples (caecal and ileal contents). The microbiota of excreta, dust, litter, caecal and ileal contents (n = 110) was assessed using 16S ribosomal RNA gene amplicon sequencing. Of the operational taxonomic units (OTUs) detected in caecal contents, 99.7% were also detected in dust, 98.6% in litter and 100% in excreta. Of the OTUs detected in ileal contents, 99.8% were detected in dust, 99.3% in litter and 95.3% in excreta. Although the majority of the OTUs found in invasive samples were detected in non-invasive samples, the relative abundance of members of the microbial communities of these groups were different, as shown by beta diversity measures. Under the conditions of this study, correlation analysis showed that dust could be used as a proxy for ileal and caecal contents to detect the abundance of the phylum Firmicutes, and excreta as a proxy of caecal contents for the detection of Tenericutes. Similarly, litter could be used as a proxy for caecal contents to detect the abundance of Firmicutes and Tenericutes. However, none of the non-invasive samples could be used to infer the overall abundance of OTUs observed in invasive samples. In conclusion, non-invasive samples could be used to detect the presence and absence of the majority of the OTUs found in invasive samples, but could not accurately reflect the microbial community structure of invasive samples

The Decline of PUVA Therapy in Vietnam: Effective Treatment of Narrow Band UVB in Vietnamese Vitiligo Patients

AIM: To examine the efficacy and safety of Narrowband ultraviolet B (NB-UVB) in Vietnamese vitiligo patients. METHODS: We recruited thirty-one patients (14 males, 17 females), aged from 7 to 67 years, with both segmental vitiligo (SV) and non-segmental vitiligo (NSV), treated three times weekly with NB-UVB. The starting dose for adults from 15 years old and children less than 15 years old was 200 mJ/cm2 and 150 mJ/cm2, respectively, with 50 mJ/cm2 and 20 mJ/cm2 dose increments at each subsequent visit, respectively, until mild erythema lasting less than 24 hrs reported by patient, given for a period of 6 months. Response to therapy was assessed based on VASI score changes. RESULTS: Based upon our results, 38.7% (12/31) of patients achieved a very good response of more than 50% VASI changes, 41.9% (13/31) obtained a good response (VASI changed from 25 to 50%). Total good and very good response to therapy significantly increased with prolonged treatment, increasing from 19.4% to 64.5% and 80.6% after 2, 4 and 6 months, respectively. Localised NSV patients obtained good and very good response significantly more frequently than generalised NSV (55.6% versus 18.2%). Adverse effects were minimal, of which one case developed herpes simplex, and 4 cases reported mild photo burn reaction which completely disappeared after adjusting the dose. CONCLUSION: NB-UVB therapy is an effective and safe tool in the management of Vietnamese vitiligo patients

The influence of human genetic variation on early transcriptional responses and protective immunity following immunization with Rotarix vaccine in infants in Ho Chi Minh City in Vietnam : a study protocol for an open single-arm interventional trial [awaiting peer review]

Background: Rotavirus (RoV) remains the leading cause of acute gastroenteritis in infants and children aged under five years in both high- and low-middle-income countries (LMICs). In LMICs, RoV infections are associated with substantial mortality. Two RoV vaccines (Rotarix and Rotateq) are widely available for use in infants, both of which have been shown to be highly efficacious in Europe and North America. However, for unknown reasons, these RoV vaccines have markedly lower efficacy in LMICs. We hypothesize that poor RoV vaccine efficacy across in certain regions may be associated with genetic heritability or gene expression in the human host. Methods/design: We designed an open-label single-arm interventional trial with the Rotarix RoV vaccine to identify genetic and transcriptomic markers associated with generating a protective immune response against RoV. Overall, 1,000 infants will be recruited prior to Expanded Program on Immunization (EPI) vaccinations at two months of age and vaccinated with oral Rotarix vaccine at two and three months, after which the infants will be followed-up for diarrheal disease until 18 months of age. Blood sampling for genetics, transcriptomics, and immunological analysis will be conducted before each Rotarix vaccination, 2-3 days post-vaccination, and at each follow-up visit (i.e. 6, 12 and 18 months of age). Stool samples will be collected during each diarrheal episode to identify RoV infection. The primary outcome will be Rotarix vaccine failure events (i.e. symptomatic RoV infection despite vaccination), secondary outcomes will be antibody responses and genotypic characterization of the infection virus in Rotarix failure events. Discussion: This study will be the largest and best powered study of its kind to be conducted to date in infants, and will be critical for our understanding of RoV immunity, human genetics in the Vietnam population, and mechanisms determining RoV vaccine-mediated protection. Registration: ClinicalTrials.gov, ID: NCT03587389. Registered on 16 July 2018

The Effectiveness of Oral Mini-Pulse Methylprednisolonein - the Treatment of Alopecia Areata in Vietnam

BACKGROUND: Systemic corticosteroid is used to treat alopecia areata, but it is associated with side effects. Mini-pulse therapy is thought to be effective but able to reduce side effects. AIM: The study aimed to evaluate the effectiveness of oral mini-pulse methylprednisolone in the treatment of alopecia areata. METHODS: Patients received methylprednisolone 16 mg orally for 2 consecutive days every week. RESULTS: After 3 months, among patients, 40% recovered well, and 55.6% recovered fairly. After 6 months, 82.2% recovered well, 17.8% recovered fairly. No adverse events were detected, and the recurrence rate was low (2.2%). CONCLUSION: Oral mini-pulse methylprednisolone therapy is an effective and safe therapeutic option for alopecia areata without side effects, and the time of the treatment is short

Whole genome analysis reveals the diversity and evolutionary relationships between necrotic enteritis-causing strains of Clostridium perfringens

BACKGROUND: Clostridium perfringens causes a range of diseases in animals and humans including necrotic enteritis in chickens and food poisoning and gas gangrene in humans. Necrotic enteritis is of concern in commercial chicken production due to the cost of the implementation of infection control measures and to productivity losses. This study has focused on the genomic analysis of a range of chicken-derived C. perfringens isolates, from around the world and from different years. The genomes were sequenced and compared with 20 genomes available from public databases, which were from a diverse collection of isolates from chickens, other animals, and humans. We used a distance based phylogeny that was constructed based on gene content rather than sequence identity. Similarity between strains was defined as the number of genes that they have in common divided by their total number of genes. In this type of phylogenetic analysis, evolutionary distance can be interpreted in terms of evolutionary events such as acquisition and loss of genes, whereas the underlying properties (the gene content) can be interpreted in terms of function. We also compared these methods to the sequence-based phylogeny of the core genome. RESULTS: Distinct pathogenic clades of necrotic enteritis-causing C. perfringens were identified. They were characterised by variable regions encoded on the chromosome, with predicted roles in capsule production, adhesion, inhibition of related strains, phage integration, and metabolism. Some strains have almost identical genomes, even though they were isolated from different geographic regions at various times, while other highly distant genomes appear to result in similar outcomes with regard to virulence and pathogenesis. CONCLUSIONS: The high level of diversity in chicken isolates suggests there is no reliable factor that defines a chicken strain of C. perfringens, however, disease-causing strains can be defined by the presence of netB-encoding plasmids. This study reveals that horizontal gene transfer appears to play a significant role in genetic variation of the C. perfringens chromosome as well as the plasmid content within strains