Fecal Samples Research Articles

Factors Associated With Missing Biological Samples in the Dog Ageing Project.

The Dog Aging Project (DAP) is a longitudinal study examining aging in US companion dogs, where missing data pose a challenge to result validity and statistical power. Early recognition and procedural adjustments are vital to address missing samples. This research assesses missing biospecimen samples within the PRECISION cohort of the DAP, aiming to identify contributing factors and propose mitigation strategies. Ninety sample kits collected between August 2021 and October 2021 were evaluated for the missingness of individual kit components. A primary assessment reviewed the missingness of each sample type with hypothesized associated factors. A secondary assessment addressed the missingness of plasma and serum aliquots made after check-in. EDTA samples for flow cytometry, peripheral blood mononuclear cells (PBMCs), DNA and biobanking were missing at rates of 18.9%, 13.3%, 6.7% and 5.6%, respectively. Faecal samples were missing at 5.6%. Urine and plasma were each missing at 2.2%. Serum, hair and dried blood spot cards were each missing at 1.1%. No statistically significant difference in missingness was seen across regions, ease of blood collection, or cooperativeness of dog during sample collection. Higher time-to-receipt was associated with a higher missingness proportion. Increasing missingness proportions were seen across plasma and serum aliquots that were created in sequential order. The study suggests reevaluating sample collection instructions to address frequently missing sample types and prevent further loss. Investigation into collection procedures for these types is recommended to identify potential causes of sample yield loss.

Sex specific gut-microbiota signatures of resilient and comorbid gut-brain phenotypes induced by early life stress

BackgroundAlterations in gut-brain axis communication pathways and the gut microbiota ecosystem caused by early life stress have been extensively described as critical players in the pathophysiology of stress-induced disorders. However, the extent to which stress-induced gut microbiota alterations manifest in early life and contribute to the sex-specific susceptibility to distinct gut-brain phenotypes in adulthood has yet to be defined. MethodsMale and female Sprague-Dawley rat offspring underwent maternal separation (3h/day from postnatal day 2–12). Faecal samples were collected before weaning for gut microbiota 16S rRNA sequencing and metabolomic analysis. Visceral pain sensitivity and negative valence behaviours were assessed in adulthood using colorectal distension and the forced swim test respectively. Behavioural data were processed in a two-step cluster analysis to identify groupings within the dataset. Multi-omics analysis was carried out to investigate if the microbial signatures following early life stress were already defined according to the membership of the adult behavioural phenotypes. ResultsMaternal separation resulted in increased visceral hypersensitivity while showing a trend for a sex-dependent increase in negative valence behaviour in adulthood. The cluster analysis revealed four clusters within the dataset representing distinct pathophysiological domains reminiscent of the behavioural consequences of early-life stress: 1. resilient, 2. pain, 3. immobile and 4. comorbid. The early life gut microbiota of each of these clusters show distinct alterations in terms of diversity, genus level differential abundance, and functional modules. Multi-omic integrations points towards a role for different metabolic pathways underlying each cluster-specific phenotype. ConclusionOur study is the first to identify distinct phenotypes defined by susceptibility or resilience to gut-brain dysfunction induced by early life stress. The gut microbiota in early life shows sex-dependent alterations in each cluster that precede specific behavioural phenotypes in adulthood. Future research is warranted to determine the causal relationship between early-life stress-induced changes in the gut microbiota and to understand the trajectory leading to the manifestation of different behavioural phenotypes in adulthood.

Enhanced detection of Opisthorchis viverrini infection: A comparative evaluation of modified one-step FECT and conventional diagnostic methods in low-intensity setting

The formalin-ethyl acetate concentration technique (FECT) is one of the most sensitive diagnostic method not only for all helminths, but also for Opisthorchis viverrini infections in stool examinations. However, it remains a diagnostic problem for light infections. We modified the one-step FECT to determine the low-intensity of O. viverrini infection and compared with various conventional detection methods. The study utilized 160 egg-positive and 160 randomly negative stool samples for O. viverrini eggs by conventional FECT (cFECT) to compare the methods, including the simple smear, the Kato-Katz method, the two commercial stool examination kits, and the one-step FECT. Our results showed that the one-step FECT method had the highest sensitivity (95.6 %), followed by cFECT (87.9 %), the Kato-Katz (55.5 %), Aquisfek SF-FIX (48.3 %), simple smear (42.3 %), and Mini Parasep® SF (35.1 %). The ability of one-step FECT exhibited better ability to detect low parasite intensities compared to the cFECT (18 eggs per gram (e.p.g.) versus 34 e.p.g.) and the other conventional diagnostic methods. In addition, the investigation of O. viverrini infection in endemic regions in northeastern Thailand based on 3900 fecal samples revealed that the one-step FECT with an intensity of 66.8 e.p.g. (range 18–226) was significantly higher in sensitivity than cFECT, which had an intensity of 58.0 e.p.g. (range 34–214). Interestingly, fecal samples with less than 50 e.p.g. could not be detected by cFECT in 67 % of cases, and 69 out of 3900 samples were negative. In conclusion, one-step FECT improves the detection of low-intensity O. viverrini infection, which is suitable for parasites screening, especially for low-intensity infections in the community.

Assessing exposure risk to microplastics by Indian Ocean pygmy blue whales

Microplastics (MPs) have attracted widespread attention due to their ubiquitous occurrence and harmful effects, however, limited data are available regarding the quantity and composition of MPs ingested by blue whales. In this study, MPs were detected in fecal samples obtained from pygmy blue whales (Balaenoptera musculus brevicauda) (n = 18, mean 0.82 items/g d.w) and seawater samples (n = 5, mean 143 ± 60.0 items/m3) from the northern Indian Ocean. Six polymer types were identified using micro-Fourier-transform infrared spectroscopy (μ-FTIR), nearly half of which were polyethylene terephthalate (PET). The variety of shapes, colors, and polymer types of MPs in blue whale fecal samples indicated the diversity of ingested MPs. For pygmy blue whales, MP ingestion exposure was estimated as high as 1.74 (± 0.83) × 106 items/day according to typical filter-feeding rates estimated for this sub-species. We suggested that the ingested MPs were mainly from trophic transfer rather than environmental exposure, and this MP ingestion may pose a minimal risk of caloric deficit. This study provides essential baseline information on the MP loads in pygmy blue whales in the Indian Ocean and considers the potential adverse impacts of long-term exposure to MPs.

Long-term changes in the gut microbiota before and after bismuth quadruple therapy or concomitant therapy in children with peptic ulcers receiving Helicobacter pylori eradication.

Helicobacter pylori (H. pylori) is a gram-negative spiral bacterium that can cause peptic ulcers. The effects of bismuth quadruple therapy and concomitant therapy on fecal ecology among children with peptic ulcers remain largely unknown. According to guidelines, these patients should be treated. Therefore, the aim of this study is to investigate the short- and long-term effects of bismuth quadruple therapy and concomitant therapy on gut microbiota in children with peptic ulcer disease (PUD). Forty-two patients with PUD were enrolled and collected their fecal samples in Shanghai. A 16S ribosomal RNA (rRNA)-based analysis was conducted. The impacts of bismuth quadruple therapy and concomitant therapy on the gut microbiota were compared before eradication and at 2, 6 and 52 weeks (12 months) after eradication. Whatever bismuth quadruple therapy and concomitant therapy, the diversity and richness of gut microbiota markedly decreased and fecal microbiota structure markbly changed at week 2. At week 6, the composition a returned to the baseline level; nevertheless, the diversity and richness gradually returned to baseline until week 52. Compared to those in the healthy control group, the relative abundances of 90% (18/20) of the bacterial genera differed at week 2, 15% (3/20) of the bacterial genera differed at week 6, and 10% (2/20) of the bacterial genera were not restored at week 52. Both bismuth-containing therapy and concomitant therapy resulted in transient changes of the gut microbiota in Chinese children, and these changes nearly returned to pre-eradication levels 1 year after eradication, suggesting the long-term safety of H. pylori therapy in children with peptic ulcers.

PREBIOTIC EFFICACY OF DEFATTED FENUGREEK SEED FLAKES (FENUFLAKESTM): A SHORT-TERM COLONIC SIMULATION STUDY

Objective: To investigate the prebiotic effects of defatted fenugreek seed flakes (Fenuflakes™) using a 48-hour colonic simulation model. Methods: Fecal samples from three healthy adult human donors were exposed to treatment conditions of blank (medium control), Fenuflakes, or inulin (fiber control). The effects on microbial fermentation (pH and gas production), metabolite production [Short Chain Fatty Acid (SCFAs), Branched-Chain Fatty Acid (BCFA), ammonium and lactate production], and microbial community composition were evaluated at 0, 6, 24, and 48 h. Results: In comparison to inulin, Fenuflakes demonstrated a significant reduction in gas production. Both inulin and Fenuflakes significantly increased beneficial SCFAs, but no significant change was observed in BCFA. Ammonium production increased upon Fenuflakes treatment due to a residual protein fraction reaching the colon, in contrast to inulin, which is in a protein-depleted state. The lactate levels significantly increased for Fenuflakes and inulin. The presence of Fenuflakes and inulin resulted in favorable fermentation by the colonic gut microbiota, indicating an increase in species enrichment and alpha diversity in the microbial community composition. Conclusion: Fenuflakes exhibit prebiotic potential by increasing SCFA and promoting the enrichment of several beneficial colonic bacteria while maintaining normal colonic pH and producing less gas than inulin.

Cestodes in Eurasian wolves (Canis lupus lupus) and domestic dogs (Canis lupus familiaris) in Switzerland

Eurasian wolves (Canis lupus lupus) and domestic dogs (Canis lupus familiaris) are definitive hosts of numerous cestode species. While infections with adult stages in canids are usually subclinical, some species pose a zoonotic risk or cause infections in wildlife and livestock, resulting in disease and/or economic losses. This study aimed to determine the prevalence, species composition, and geographical distribution of cestode infections in dogs and free-ranging wolves in Switzerland. Faecal samples from 2,065 dogs and intestinal content from 121 necropsied wolves were macroscopically examined and tested using zinc chloride flotation method. When cestode eggs or adult cestodes were detected, a molecular identification based on multiplex-PCR and sequencing was performed. In the sampled wolves, the prevalence by flotation (42/121; 34.7%) was lower than the overall prevalence including macroscopic examination (76/121; 62.8%). The flotation method thus failed to detect cestode infections in 44.7% (34/76) of infected wolves. The most frequently detected species was Taenia hydatigena (46/121; 38.0%), followed by Taenia serialis (23/121; 19.0%), Mesocestoides spp. (3/121; 2.5%), Taenia ovis (1/121; 0.8%), and Echinococcus multilocularis (1/121; 0.8%). In the analysed dogs, the prevalence was 0.9% (19/2,065), but the real prevalence is very likely to be higher, as no necropsy data were available. Identified cestode species included Taenia crassiceps (6/2,065; 0.3%), E. multilocularis (3/2,065; 0.1%), Mesocestoides sp. (2/2,065; 0.1%), Taenia polyacantha (1/2,065; 0.05%), and Dibothriocephalus latus (1/2,065; 0.05%). By identifying the cestode species infecting two closely related host species with markedly different lifestyles, this study sheds light on the local distribution of these parasites and their potential impacts on wildlife, livestock, and human health. Due to their close contact with humans, infected dogs represent an important source of infection with zoonotic cestodes such as Echinococcus spp. and certain Taenia species, responsible for serious human diseases.

The effects of casein glycomacropeptide on general health status in children with PKU: A randomized crossover trial

In PKU, it is suggested that casein glycomacropeptide based protein substitute (GMP) may have physiological advantage when satiety, oxidative stress, renal function and inflammation are considered. Its prebiotic properties may also help gastrointestinal (GI) tolerance.In children with PKU, a randomized/crossover trial comparing phenylalanine-free amino acids (AA) vs GMP as the single source of protein substitute for 12-weeks in each arm was conducted. There was a 4-week wash out period with AA in-between. At baseline and end of each intervention, blood and fecal samples were taken to monitor gut health, oxidative stress, renal function, inflammatory markers and plasma amino acids. Satiety and Pediatric Quality of Life (PedsQL) GI symptoms questionnaires were completed. Usual weekly blood spots for phenylalanine and tyrosine were done.Twelve patients (8 males; aged 4-9y) with PKU participated. GMP improved the following GI symptoms: stomach pain (p = 0.003), heartburn and reflux (p = 0.041) and wind/ bloating (p = 0.018). With GMP, there was also a trend for less constipation (p = 0.068), discomfort with eating (p = 0.065) and nausea and vomiting (p = 0.087). There was no changes on stool gut health markers (IgA, short chain fatty acids and fecal calprotectin). There were no statistically significant differences for renal, oxidative stress, inflammatory and gut health markers or measures of satiety except for adiponectin (p = 0.028) and total antioxidant capacity (p = 0.049), although the latter was possibly without clinical significance. Mean dried blood spot Phe was 114 μmol/L higher with GMP vs AA (p < 0.001). There was no difference in tyrosine levels. In conclusion, GI symptoms significantly improved with GMP versus AA. The phenylalanine content of GMP may present challenges when it is used as the only protein substitute in children with classical PKU with low Phe tolerance.

Don't forget the dams! Dairy cows' responses to two separation methods after 3 months of cow-calf contact

Weaning and separation remain among some of the biggest challenges for cow-calf contact systems, making the development of practical and low stress separation methods mandatory for future success of these systems. This study aimed to compare behavioral and physiological responses of dairy cows to separation from their calves after 3 mo of full-time contact with either the 2-step method (NF, 2 wks full-time contact while calves wore a nose flap, 1 wk fence-line contact before total separation, n = 18) or by gradual reduction of contact time between cow and calf (GR, 1 wk half day contact, 1 wk morning contact, 1 wk fence-line contact before total separation, n = 18). Vocalizations and searching behavior were observed on 4 d/wk from 1 wk before separation until 1 wk after total separation. During the same period, lying behavior and rumination time was automatically assessed via accelerometers and pressure sensors. Fecal and blood samples were collected twice/wk from day -1 till +23 relative to separation start for analysis of fecal cortisol metabolites and the immune response. Milk yield in the parlor was continuously recorded. Statistical analysis was conducted using linear mixed effects models. We found no difference between the 2 separation methods in any of the examined behavioral and physiological response variables. However, a significant increase in vocalizations and searching behavior compared with baseline was present with both methods. Further, there was a transient increase in physiological distress markers and a short-lived retention of milk yield at initiation of treatments, indicating that both methods induced distress for the cows. Descriptively, there were large inter-individual differences between cows as well as a different temporal distribution in occurrence of behavioral responses, as GR cows vocalized most frequently during the week with fence-line contact and after total separation from the calf, while NF cows reacted strongest during the 2 wks while calves wore the nose flap. Milk yield was higher in NF than GR cows during the 2 wks while GR calves had time-restricted access to their dams and NF calves were prevented from suckling, but showed no difference afterward anymore. However, similar evening milk yields of GR cows in the weeks with half day and morning contact, indicated that the weekly reductions in contact time worked in a rather stepwise than gradual manner, which warrants further improvement of the GR method. Taken together, results showed that cows experienced distress during separation with the GR method, when implemented over 3 wks in 3 steps, as well as with the NF method, but differences between individuals were considerable.

Parasitic fauna of wild boars (Sus scrofa) from the northwestern region of São Paulo state, Brazil.

In Brazil, the wild boar (Sus scrofa) is the main invasive exotic species, responsible for causing various economic, environmental, and health damages to biodiversity. In view of the above, we aimed in our study to investigate the occurrence of endo and ectoparasites in free-ranging wild boars in the northwest region of the state of São Paulo, Brazil. In total, 45 animals of different sexes and ages were examined in this research. Fecal and urine samples were processed using coproparasitological techniques. Multiple incisions in muscles, liver, and pancreas were also made to investigate cestodes and trematodes, and the entire epidermal region of the animals was analyzed for ectoparasites search. In our study, we demonstrate an occurrence of 97.77% (44/45) and 43.33% (13/30) of endo and ectoparasites, respectively, in wild boars, with the identification of eggs of Metastrongylus spp., Strongyloides ransomi, Trichuris suis, Stephanurus dentatus, and nematodes of the order Strongylida, as well as oocysts of Eimeriidae protozoa. Ectoparasite infestations were mainly caused by ixodids of the genus Amblyomma spp. and by larvae of Cochliomyia hominivorax.

Microbiota-derived lysophosphatidylcholine alleviates Alzheimer's disease pathology via suppressing ferroptosis.

Alzheimer's disease (AD) is a pervasive neurodegenerative disorder, and new approaches for its prevention and therapy are critically needed. Here, we elucidate a gut-microbiome-brain axis that offers actionable perspectives for achieving this objective. Using the 5xFAD mouse model, we identify increased Clostridium abundance and decreased Bacteroides abundance as key features associated with β-amyloid (Aβ) burden. Treatment with Bacteroides ovatus, or its associated metabolite lysophosphatidylcholine (LPC), significantly reduces Aβ load and ameliorates cognitive impairment. Mechanistically, LPC acts through the orphan receptor GPR119, inhibiting ACSL4 expression, thereby suppressing ferroptosis and ameliorating AD pathologies. Analysis of fecal and serum samples from individuals with AD also reveals diminished levels of Bacteroides and LPC. This study thus identifies a B.ovatus-triggered pathway regulating AD pathologies and indicates that the use of single gut microbiota, metabolite, or small molecule compound may complement current prevention and treatment approaches for AD.

Prevalence of gastrointestinal and blood parasites in horses of Nakhon Si Thammarat province, Thailand

Background and Aim: The global prevalence of gastrointestinal (GI) and blood parasite infections in horses is a significant concern due to their substantial impact on morbidity, mortality, and economic losses in the horse industry. In Thailand, limited research has been conducted on these parasites in horse populations, and data from southern Thailand are lacking. Consequently, this study aimed to estimate the prevalence of GI and blood parasites in horses in Nakhon Si Thammarat province, Thailand. Materials and Methods: In total, 79 fecal and blood samples were collected from horses across 11 farms in Nakhon Si Thammarat province. The fecal examination was conducted using simple flotation, formalin-ethyl acetate sedimentation, and a modified McMaster technique. Conventional polymerase chain reaction (PCR) was used to identify blood and strongyle parasites. The influence of sex, age, and body condition score on the prevalence of GI parasites was also analyzed. Results: Six GI parasites were detected: four nematodes (Oxyuris equi, Parascaris equorum, strongyles, and Strongyloides westeri), one trematode (Gastrodiscus aegyptiacus), and one protozoan (Eimeria leuckarti). The overall prevalence of GI parasites was 74.7%, with single strongyle infections accounting for the highest proportion at 50.6%, followed by co-infections of strongyles and G. aegyptiacus at 10.1%. All 11 pooled strongyle samples were positive for cyathostomins and Strongylus vulgaris using conventional PCR with specific primers. Sex was significantly associated with the overall prevalence of GI parasites, whereas both sex and age were significant risk factors for infection by strongyle parasites. Theileria equi was the only blood parasite species detected in the surveyed horses, with a prevalence of 1.3% (n = 1/79). Conclusion: This study is the first to estimate the prevalence of GI and blood parasites in horses from Nakhon Si Thammarat province, Thailand. These findings highlight the importance of implementing control measures against GI parasites and are pivotal for developing effective infection prevention strategies. Keywords: blood parasites, gastrointestinal parasites, horses, southern Thailand.

Exploring gut microbiota diurnal fluctuation in alcohol-dependent patients with sleep disturbance.

Introduction. Alcohol dependence (AD) and sleep disturbance (SD) independently affect gut microbiota, potentially disrupting the circadian rhythm of the microbiota and the host. However, the impact of SD on the composition and rhythmicity of gut flora in AD patients remains poorly understood.Gap Statement. Characteristics of gut flora and diurnal oscillations in AD patients experiencing SD are unknown.Aim. This study aims to explore alterations in gut flora and diurnal oscillations in AD patients experiencing SD.Methodology. Thirty-two AD patients and 20 healthy subjects participated, providing faecal samples at 7 : 00 AM, 11 : 00 AM, 3 : 00 PM and 7 : 00 PM for gut microbiota analysis using 16S rDNA sequencing. AD patients were further categorized into those with poor sleep (ADwPS) and those with good sleep (ADwGS) for further analyses.Results. The ADwPS group demonstrated elevated levels of anxiety, depression and withdrawal severity compared to the ADwGS group (all P<0.05). The β-diversity of gut microbiota in the ADwPS group differed from that in the ADwGS group (P<0.05). Bacterial abundances at various taxonomic levels, including Cyanobacteria and Pseudomonadales, differed between the ADwPS and ADwGS groups (all P<0.05). Utilizing unweighted UniFrac analysis, the β-diversity of gut microbiota in the ADwPS group demonstrated robust diurnal oscillation (P<0.05), whereas this pattern was statistically insignificant in the ADwGS group. Notably, the abundance of pathogenic bacteria like Pseudomonadales and Pseudomonadaceae exhibited marked diurnal fluctuation in the ADwPS group (all P<0.05).Conclusion. SD in AD patients extends beyond alcohol-induced alterations, impacting gut microbiota composition, function and diurnal oscillation patterns. This highlights its add-on influence, supplementing AD-related changes.

Changing Bird Migration Patterns Have Potential to Enhance Dispersal of Alien Plants From Urban Centres

ABSTRACTThere is increasing recognition that alien species may be ‘sleepers’, becoming invasive with favourable changes in conditions, yet these changes remain difficult to predict. As populations of frugivorous birds shift with urbanisation and climate change, they could provide dispersal services for introduced fruiting plants that have previously been considered benign. This is likely to be especially problematic at higher latitudes where bird migration phenologies are altering rapidly. However, any consequences for fruit dispersal have not yet been explored. Here, we use Helsinki, Finland, to investigate whether (i) streetscapes provide birds with a fruit resource that differs from urban forest fragments and (ii) the chances for dispersal of alien species (i.e., preferential consumption of native fruits). While there were both more fruits and birds in streetscapes (replicated across multiple years), fruits were not consumed preferentially according to origin. Additionally, seed analysis from faecal samples of blackbird Turdus merula L., a previously migratory but increasingly resident species, suggested that alien and native plants are equally likely to be dispersed. These results indicate that birds could be dispersing alien species more frequently than previously thought and highlight the complex effects of changing climates on potentially invasive species.

All in the Details: A First Assessment for the Viability of Metabarcoding in Diet Composition Analysis of African Wild Dogs (Lycaon pictus).

DNA metabarcoding is a contemporary technique in diet composition studies and stands to fill key knowledge gaps left by traditional diet analysis methods. For endangered species such as the African wild dog (Lycaon pictus), the fulfilment of these knowledge gaps presents an opportunity for improved management practices and vulnerability assessments. There are an estimated ~600 African wild dogs remaining in South Africa. These dogs are generally understood to prey upon impala (Aepyceros melampus) and other medium-sized ungulates. Here, we present the first assessment of DNA metabarcoding as a valuable method for diet composition analysis of this highly social carnivore. DNA from faecal samples collected across seven landscape types in the Kruger National Park (KNP) was extracted and used to determine the presence of seven unique prey taxa, including novel species such as the Cape hare (Lepus capensis). Impala was identified as a prey item in all landscape types, complementing the diet preference prediction made with stable isotope analysis using the same samples and existing understanding of wild dog diet. Given recommended improvements, the application of DNA metabarcoding in wild dog diet analysis shows promising prospects for identifying novel prey species and validating previous records of this endangered canids diet.

Metagenomics and selective culture reveal the major transfer and prevalence of antibiotic resistance genes in Tibetan Plateau animals

The Tibetan Plateau, despite being the highest and least populated plateau on the Earth, harbors antibiotic-resistant bacteria (ARBs) as well as antibiotic resistance genes (ARGs) in its pristine environment and animals. There is, however, limited knowledge regarding antibiotic resistance in Tibetan Plateau animals. Here, fecal samples of grazing yaks and intestinal content samples of wild rats were collected at altitudes of 2920m and 4360m and subjected to selective culture, PCR, and metagenomic sequencing. The results revealed a higher antibiotic resistance rate in low-altitude regions than in high-altitude regions. The simultaneous presence of bacteria exhibiting different antibiotic resistance phenotypes across multiple samples suggests the potential emergence of multidrug-resistant strains within the animal gut microbiota. Pseudomonas spp. and Escherichia coli were the predominant ARBs. In contrast to low-altitude regions with frequent human activities, ARG dissemination in the Tibetan Plateau did not show a significant correlation with mobile genetic elements. ARGs in high-altitude regions relied more on vertical gene transmission. This study expands our knowledge of antibiotic resistance in grazing and wild animals inhabiting the Tibetan Plateau, thereby highlighting the potential threat posed by antibiotic resistance in this region.

Ramming the parasites: Evaluation of quarantine procedures against Haemonchus contortus at sheep markets in Sweden

In Sweden, it is recommended to treat rams at sheep markets with ivermectin and then keep them in quarantine to minimise the risk of transmission of Haemonchus contortus between farms. The aim of this study was to evaluate the effectiveness of this practise. Accordingly the gastrointestinal parasite status of 50 rams purchased at two sheep markets in central Sweden in autumn 2019 was investigated using faecal samples collected on the day of sale (test 1), 12 ± 3 days after ivermectin injection (test 2, in quarantine) and a few months later before inclusion in the new flocks (test 3). We used both traditional diagnostic methods (i.e. identification of nematode eggs in faeces or larvae in cultures when H. contortus eggs could not be identified) and a molecular test based on the digital droplet PCR platform to further identify positive samples. In test 1, conducted in autumn, 40 % of rams were FEC-positive, but only 12 % (six rams) were infected with H. contortus according to conventional routine diagnostics. In test 2, 8 % (four rams) were FEC-positive, including one with 1050 eggs, 90 % of which were identified as H. contortus. This ram was therefore returned to the supplier. However, ivermectin was found to be effective when this animal and a group of lambs from the same farm were treated and tested again. Test 3 was performed on 44 of the same rams (in addition to the returned ram, two rams died in quarantine and the samples from three rams were never provided by the owners). The proportion of FEC-positive animals was 42 %, with an even higher proportion (27 %) of animals being H. contortus-positive than in test 1. The corresponding results for tests 1, 2 and 3 with the ddPCR assay were 18 %, 4 % and 76 %, respectively. This study demonstrates the superiority of DNA detection over microscopy, which is the mainstay in most diagnostic laboratories. Although the combined results confirm that H. contortus survived quarantine in two rams, in the other cases it is not clear whether the spring infection rates are due to re-emergence of persistent larvae from quarantine or reinfection on the new farm. These results suggest not only that we should recommend that sheep farmers use a more sensitive molecular test when purchasing and introducing new animals to their flock, but also that the reliability of injectable ivermectin as a quarantine treatment for removal of adult and larval stages needs further investigation.

Low detection of H5N1 virus in commercial chickens with a low-level of vaccination coverage against H5N1 virus infection in Bangladesh

BackgroundBangladesh has reported > 560 H5N1 outbreaks in poultry and eight human cases since 2007. Commercial chicken farms were mostly affected. Commercial chicken farms across the country use imported vaccines against H5N1 virus; however, these vaccines did not use local circulatory isolates of H5N1virus. Vaccination may have limited effectiveness in chicken because of the mismatch in terms of subtypes and clades. To test this, we conducted a mixed-method study to assess the impact of ongoing vaccination against H5N1 virus on H5N1 viral shedding through freshly dropped feces of chickens raised in commercial farms that exclusively vaccinated or did not vaccinate their chickens.MethodsInitially, we collected vaccination coverage data from all active farms in a subdistrict of each of eight division. In each district, 25 vaccinated and 25 non-vaccinated chicken farms were selected randomly for sample collection. All samples were tested to detect avian influenza viruses using rRT-PCR.ResultsA total of 5092 poultry farms were surveyed; among them 1284 (25%) chicken farms administered vaccine against H5N1 virus. In total 21 of 400 tested farms (5%) had chicken feces samples that tested positive for AIVs; of these three were positive for H5N1 subtype of clade 2.3.2.1. Out of three H5N1 positive farms, 1 (33%) was vaccinated and 2 (67%) were unvaccinated. The chicken farms that administered vaccine against H5N1 was found protective for the detection of H5N1 viral RNA (aOR 0.39, 95% CI: 0.32–0.48). The H5N1 isolates of clade 2.3.2.1 sequenced in this study formed a cluster with the vaccine strain A/duck/Guangdong/S1322/2010 (H5N1) [Re-6].ConclusionsThe overall low vaccination coverage with low detection of H5N1 virus in commercial chickens makes it difficult to assess the effectiveness of the vaccine in reducing H5N1 viral shedding.

Lactiplantibacillus plantarum P101 Ameliorates TiO2 NP-Induced Bone Injury in Young Rats by Remodeling the Gut Microbiota and Inhibiting the Production of Pro-Inflammatory Cytokines.

To evaluate the therapeutic effect of oral administration of Lactiplantibacillus plantarum P101 (P101) on skeletal injury in young rats exposed to titanium dioxide nanoparticles (TiO2 NPs), and explore the potential mechanism. Four-week-old male rats were orally administration to TiO2 NPs and supplemented with P101 2hours later for 4weeks. The growth and development, food intake, bone metabolism and serum inflammatory markers of the rats were evaluated. Their tibias were observed and evaluated using microcomputed tomography (micro-CT), tartrate-resistant acid phosphatase (TRAP) staining, immunohistochemistry (IHC) and real-time quantitative PCR (RT-qPCR). We observed the tibia growth plate using safranin and fast green staining. 16S rDNA sequence analysis of fecal samples was performed to observe changes in the gut microbiota. Our results showed that TiO2 NPs can lead to bone growth inhibition and osteoporosis, induce intestinal flora imbalance, and induce inflammation in young rats. Further mechanistic studies suggested that TiO2 NPs disrupts intestinal flora and increases serum IL-1β levels, which increased the expression of RANKL in bone, thereby enhancing osteoclast differentiation and function, leading to bone loss. Through a P101 supplementation experiment, we found that P101 ameliorated the inflammation and osteoporosis on bone caused by TiO2 NPs. This study showed that the mechanism by which P101 alleviates bone damage caused by TiO2 NPs may be through restoring intestinal microbial homeostasis and inhibiting inflammatory response.

Impact of postpartum hospital length of stay on infant gut microbiota: a comprehensive analysis of vaginal and caesarean birth

BackgroundThe primary concern with prolonged hospitalization following birth is the risk of acquiring hospital-acquired infections (HAIs) caused by opportunistic bacteria, which can alter the early establishment of gut microbiota. ObjectiveThis study aimed to assess the association between postpartum hospital length-of-stay (LOS) and the composition of gut microbiota at 3 and 12 months of age according to birth mode. MethodsA total of 1313 Canadian infants from the CHILD Cohort Study were involved in this study. Prolonged hospital LOS was defined as > 2 days following vaginal and > 3 days after caesarean section (CS) birth. Infants' gut microbiota was characterized by Illumina 16S rRNA sequencing of faecal samples at 3-4 months and 12 months. FindingsFollowing a prolonged hospital LOS, vaginally-delivered (VD) infants with no maternal intrapartum antibiotic (IAP) exposure had a higher abundance of bacteria in their gut known to cause HAIs, including Enterococcus at 3 and 12 months, Citrobacter at 3 months and C. difficile at 12 months. Enterococcus or Citrobacter abundance at 3 months significantly mediated the association between LOS, and low abundance of Bacteroidaceae, or higher Enterococcaeae/Bacteriodaceae or Enterobacteriaceae/Bacteroidaceae abundance ratios at 12 months of age in VD infants without IAP exposure. HAI-causing Enterobacteriaceae were also more abundant in later infancy with a longer hospital LOS following CS. In the absence of exclusive breastfeeding for 3 months or any breastfeeding at 12 months, the Porphyromonadaceae (of Bacteroidota) become depleted in CS infants with a prolonged LOS. ConclusionsProlonged hospital stay after birth is associated with infant gut dysbiosis.