Search Results (37)

Triticale (Triticosecale Wittmack) is a versatile forage crop valued for its high yield, balanced nutrition, and environmental adaptability. However, the dough-stage triricale has higher dry matter and starch content but lower water-soluble carbohydrate levels than earlier stages, posing fermentation challenges that may impair silage quality. This study aimed to investigate the effects of lactic acid bacteria inoculation on the fermentation quality, bacterial community, and metabolome of whole-plant triticale silage at the dough stage. Fresh triticale was ensiled for 30 days without or with an inoculant containing Lactiplantibacillus plantarum and Streptococcus bovis. Fermentation quality, bacterial succession, and metabolic profiles were analyzed at multiple time points. Inoculation significantly improved fermentation quality, characterized by a rapid pH drop, increased lactic acid production, and better preservation of fiber components. Microbial analysis revealed that inoculation successfully established Lactobacillus as the dominant genus while suppressing spoilage bacteria like Enterobacter and Clostridium. Metabolomic analysis on day 30 identified numerous differential metabolites, indicating that inoculation primarily altered pathways related to amino acid and purine metabolism. In conclusion, inoculating dough-stage triticale with this LAB combination effectively directs the fermentation trajectory. It enhances silage quality not only by optimizing organic acid profiles and microbial succession but also by modulating key metabolic pathways, ultimately leading to improved nutrient preservation. Full article

A 74-year-old patient presented to the emergency department with aggravating asthenia and persistent fever over the course of the last 2 weeks. He benefited 3 years prior from a self-expandable transcatheter aortic valve implantation (TAVI) for symptomatic severe aortic valve stenosis, as he refused open heart surgery. The blood workup showed leukocytosis and high C-reactive protein levels. However, the microbiological analysis remained negative. During his hospital stay, a transesophageal echocardiogram was performed, which showed thickening of the transcatheter heart valve leaflets and a vegetation of almost 2 cm attached to the stent of the TAVI. A high suspicion of endocarditis was established at this stage even in the absence of microbiological documentation. Surgery showed extensive damage to the prosthesis and consisted of the careful disengagement of the TAVI followed by a successful aortic valve replacement. The microbiological analysis of the excised TAVI identified Streptococcus bovis as the culprit bacteria. The patient fully recovered at the 1-year follow-up. TAVI endocarditis is a source of emerging new challenges, as they are becoming more frequent due to the increase in TAVI procedures, can affect the leaflets and the stent, and can present destructive evolution even with less aggressive bacteria, while remaining amenable to surgical treatment. Full article

Background: Neonatal sepsis is a major cause of infant mortality, and it accounts for a significant consumption of antimicrobials in paediatrics. This is the first comprehensive study on neonatal sepsis in Hong Kong. Methods: From 2014 to 2023, all neonates admitted to a single institution with culture-proven infections from the blood and/or cerebrospinal fluid were selected and reviewed retrospectively. The infecting organisms, their antibiotic nonsusceptibility pattern, and the concordance of empirical antimicrobial therapy with the microbiological profiles were described and were further compared between infants of normal/low birth weight (≥1.5 kg) and very low/extremely low birth weight (<1.5 kg), early-onset sepsis (<72 h), and late-onset sepsis (4–28 days), the first and the second 5-year periods (2014–2018 vs. 2019–2023). Results: After contaminants were excluded, there were 118 affected neonates with 125 organisms identified. Fifty-nine were male. Thirty-four were very low/extremely low birth weight infants, and twenty-eight infants had early-onset sepsis. Patient demographics and the microbiology findings did not differ between the first 5 years and the latter 5 years. However, the incidence of neonatal sepsis was significantly lower in the latter 5 years (3.23 vs. 1.61 per 1000 live births, p < 0.001), the period that coincided with the COVID-19 pandemic. Escherichia coli was the most common Gram-negative pathogen. Streptococcus agalactiae and Streptococcus bovis group infections were more common in early-onset sepsis, while coagulase-negative Staphylococcus and non-E. coli Gram-negative pathogens were more likely to occur in late-onset sepsis. In very low/extremely low birth weight infants, the rate of cefotaxime or ceftriaxone nonsusceptibility among Gram-negative isolates was higher (p = 0.01), and concordance of empirical antimicrobial therapy was lower (p = 0.006). Conclusions: Management of neonatal sepsis remains challenging, and there is a need for optimising antimicrobial therapy, especially in preterm patients. Antepartum screening with intrapartum antibiotic prophylaxis is effective in reducing the risk of early-onset sepsis associated with S. agalactiae, while stringent infection control measures are important for the prevention of late-onset sepsis. Full article

Background: Cattle production is a cornerstone of U.S. agriculture but faces increasing pressure to balance profitability with environmental sustainability. Optimizing the ruminal microbiome to enhance feed efficiency could help address both challenges. Members of the Streptococcus bovis/Streptococcus equinus complex (SBSEC) are key contributors to ruminal acidosis and related digestive disorders due to their role in carbohydrate fermentation and lactic acid production. Bacteriophages targeting this bacterial group present a promising approach to mitigate this problem with high precision and without promoting the spread of antibiotic resistance. Methods: A collection of SBSEC-targeting bacteriophages were isolated from cattle rumen fluid and feces and further characterized. Characterization included host-range evaluation, whole genome sequencing, and growth inhibition assessment via optical density measurements. Selected bacteriophages underwent training to enhance infectivity. Results: Eleven lytic and one lysogenic phage were isolated. Several phages demonstrated sustained bacterial growth suppression, showing efficacy against SBSEC bacteria from diverse sources despite narrow host ranges. Co-evolutionary training was done in a subset of phages to improve bacteriolytic activity but had an inconsistent effect on the ability of phages to inhibit the growth of their naïve host. Genomic sequencing and phylogenetic analysis revealed uniqueness and clustering into three distinct groups that matched phenotypic characteristics. Conclusions: This study demonstrates the potential of bacteriophages as precise biological control agents, with successful isolation and enhancement of phages targeting SBSEC bacteria. Eleven lytic genome-sequenced phages show promise for development as cattle feed additives, though further research is needed to optimize their application in agricultural settings. Full article

This study introduces an innovative on-site diagnostic method for rapidly detecting the Streptococcus bovis/Streptococcus equinus complex (SBSEC), crucial for livestock health and food safety. Through a comprehensive genomic analysis of 206 genomes, this study identified genetic markers that improved classification and addressed misclassifications, particularly in genomes labeled S. equinus and S. lutetiensis. These markers were integrated into a portable quantitative polymerase chain reaction (qPCR) that can detect SBSEC species with high sensitivity (down to 10¹ or 10⁰ colony-forming units/mL). The portable system featuring a flat chip and compact equipment allows immediate diagnosis within 30 min. The diagnostic method was validated in field conditions directly from cattle udders, farm environments, and dairy products. Among the 100 samples, 51 tested positive for bacteria associated with mastitis. The performance of this portable qPCR was comparable to laboratory methods, offering a reliable alternative to whole-genome sequencing for early detection in clinical, agricultural, and environmental settings. Full article

The primary objective of this study was to explore the effects of biological additives, including Streptococcus bovis (SB), Bacillus subtilis (BS), xylanase (XT), and their combined treatments, including SB + BS (SBBS), SB + XT (SBXT), and BS + XT (BSXT), on the chemical composition, fermentation characteristics, and microbial community of high-moisture oat silage. Compared with the CK group (control group without additives), SB and SBBS treatments increased the lactic acid content (p < 0.05) and reduced the contents of acetic acid, propionic acid, butyric acid, and ammonia nitrogen in silage (p < 0.05). XT, SBXT, and BSXT treatments decreased the neutral detergent fiber and acid detergent fiber contents (p < 0.05), increasing the water-soluble carbohydrate content (p < 0.05). The SB, SBBS, and SBXT treatments increased the abundance of Lactiplantibacillus (p < 0.05) and significantly decreased microbial richness with diversity (p < 0.05), improving the microbial community structure in silage. The addition of XT increased the relative abundance of Clostridium and Enterobacteriaceae, but its combination with SB and BS increased the abundance of Lactiplantibacillus and inhibited the development of undesirable bacteria. Moreover, different additives changed the metabolism of carbohydrates, amino acids, energy, cofactors and vitamins of bacterial communities during ensiling. In summary, the addition of SB and SBBS was more conducive to improving the fermentation characteristics of oat, while XT, SBXT, and BSXT performed better in degrading lignocellulose in plants. Full article

This study evaluated the effects of clinoptilolite (CTL) and ferulic acid (FA) supplementation on in vitro ruminal fermentation characteristics, gas production, and bacterial abundance. Treatments were arranged in a 2 × 2 factorial design (FA: 0 or 300 ppm; CTL: 0 or 1%) with repeated measures over time (2, 4, 8, 12, 24, 36, 48, and 72 h). Throughout the incubation period, the CTL and FAZ treatments recorded the highest pH values (p ≤ 0.05), maintaining levels closest to neutrality after 72 h. After 48 and 72 h, FA and CTL decreased (p ≤ 0.05) the ammonia concentrations while increasing (p ≤ 0.05) acetate and propionate. The methane, butyrate, and iso-VFA concentrations were unaffected (p > 0.05) by any treatment. FA increased the total gas production throughout the experimental period (p ≤ 0.05). Additionally, FA and CTL significantly reduced the relative abundance of Ruminococcus albus and Streptococcus bovis (p ≤ 0.05), while no significant effects were observed for Selenomonas ruminantium (p > 0.05). These findings suggest that both additives can positively modify the rumen fermentation characteristics and microbial composition, which could significantly contribute to animal nutrition by providing a promising strategy for enhancing rumen fermentation. Full article

We identified alterations in the ruminal microbiome, metabolome, and epithelial inflammatory response due to moderate feed restriction (FR). Ruminal digesta and epithelial biopsies from seven ruminally cannulated Angus steers were initially collected during ad libitum access to feed (PRE). After a 10 day recovery, steers underwent a 3-day FR period (FRP) at 25% intake of PRE followed by a 15 day recovery (POST) phase with ad libitum access to feed. At the end of FRP and POST, ruminal digesta and epithelial biopsies were collected again for microbial DNA and tissue RNA extraction. RT-qPCR was applied for relative microbial abundance and RNA extraction. Metabolite profiling of digesta was performed via GC-MS. The abundance of Succinivibrio dextrinosolvens, Streptococcus bovis, and Bifidobacteria spp. (N124) was higher (p < 0.05) during FRP than PRE and POST, while Lactobacillus spp. (C25), Escherichia coli (EC42405), Fibrobacter succinogenes, and Megaspheara elsdenii abundances were lower in FRP than PRE (p < 0.05). The TNF and TLR2 mRNA abundance was greater in FRP than PRE (p < 0.05). Among 15 detected amino acids, glutamine, isoleucine, lysine, phenylalanine, threonine, and valine were lower (p < 0.05) in FRP than PRE. Metabolite pathway analysis revealed alterations in amino acid, fatty acid, vitamin, and energy metabolism during FRP (p < 0.05). The mRNA of the proinflammatory genes TNF and TLR2 in the epithelium peaked (p < 0.05) at FRP and remained higher at POST. Results indicated that a short FR influenced ruminal bacteria, reduced concentrations of most metabolites, and triggered an inflammatory response. Full article

The aim of this study was to determine the prevalence of Streptococcus (Sc.) agalactiae, Prototheca spp., Staphylococcus (S.) aureus, and especially methicillin-resistant S. aureus as well as Myco-plasmopsis (M.) spp. and M. bovis in bulk tank milk (BTM) on dairy farms in Lower Saxony, Germany. BTM samples were collected in January 2023 from 208 selected dairy farms. The samples were quantitatively culturally analyzed for S. aureus and Prototheca spp. Presumptive S. aureus colonies were further confirmed by MALDI-TOF. Presumptive Prototheca spp. colonies were confirmed by light microscopy. Sc. agalactiae and Mycoplasmopsis spp. were detected by real-time polymerase chain reaction (rtPCR). Sc. agalactiae was detected in two herds (1% (Confidence Interval 95% (CI) 0.3–3.4)). S. aureus was confirmed by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) in 38 herds (18.3% (CI 13.6–24.1)), assuming a threshold of >10 cfu/mL milk. A total of 154 isolates identified as S. aureus by MALDI-TOF were transferred to agar with added oxacillin for resistance testing, of which 19 isolates (12.3% (CI 8–18.5)) showed growth. The 19 isolates came from eight different farms (3.8% (2–7.4)). Prototheca spp. were identified in 13 herds (6.3% (CI 3.7–10.4)). Mycoplasmopsis spp. were detected by PCR in 18 herds (8.7% (CI 5.5–13.3)). Of these, M. bovis was present in three herds (1.4% (0.5–4.2)). The herd prevalence of Sc. agalactiae in BTM appears to be at low levels in the sampled area. The prevalence of Mycoplasmopsis spp. in the herds was higher than expected compared to previous studies. It is interesting to note that the percentage of M. bovis in the total Mycoplasmopsis spp. was only 16.7%. Full article

To obtain improved insights into the complex microbial aetiology of bovine mastitis, this study investigated the pathogens involved in cattle mastitis in Bosnia and Herzegovina. A total of 179 milk samples from cows with clinical mastitis (CM) and subclinical mastitis (SCM), as well as eight bulk tank milk (BTM) samples from 48 dairy farms, were analysed by standard bacteriological and mycological methods. Mycoplasma detection and identification were performed using culture techniques and real-time polymerase chain reaction (PCR). A total of 88 (49.2%) mastitis samples were positive for known mastitis pathogens at 32 of 47 farms (68.1%). Mycoplasma bovis was a predominant pathogen (25/187; 13.4%) in the majority of herds (14/48; 29.2%) and accounted for 48.9% of positive CM samples. Escherichia coli was the second most dominant CM pathogen (34%), followed by Streptococcus agalactiae (10.6%), whereas Staphylococcus aureus and coagulase-negative staphylococci were the most common in SCM samples (17.1%). Other mastitis pathogens included Candida spp. and Prototheca zopfii. Two BTM samples were positive for M. bovis only, and one was positive for a mixed culture of S. aureus and Streptococcus uberis. The finding of various causative agents of bovine mastitis, with M. bovis emerging as the main pathogen, emphasizes the significance of comprehensive testing that includes not only common mastitis pathogens but also mycoplasmas, fungi, and algae. Full article

Natural starter cultures, characterised by undefined microbiota, can contribute to the technological process, giving peculiar characteristics to artisanal fermented foods. Several species have a long history of safe use and have obtained Qualified Presumption of Safety (QPS) status from the European Food Safety Authority (EFSA), whereas others (non-QPS) could represent a potential risk for consumers’ health and must undergo a safety assessment. In this work, the biodiversity, at species and strain level, by pulsed-field gel electrophoresis (PFGE) and (GTG)₅ rep-PCR, of an undefined natural starter culture, in frozen and lyophilized form, obtained from ewe’s raw milk avoiding thermal treatment or microbial selection, was investigated. The culture was constituted by different biotypes of Enterococcus durans, Enterococcus faecium, Enterococcus faecalis, and Lacticaseibacillus paracasei. Streptococcus oralis and Streptococcus salivarius were also found, over species belonging to the Streptococcus bovis–Streptococcus equinus complex (SBSEC), like Streptococcus gallolyticus subsp. macedonicus, Streptococcus lutetiensis, and Streptococcus equinus. Molecular investigation on virulence and antibiotic resistance genes, as well as minimum inhibitory concentration (MIC) determination, revealed that all the non-QPS strains can be considered safe in the perspective of using this culture for cheesemaking. The obtainment of a natural culture directly from ewe’s raw milk bypassing thermal treatment and selection of pro-technological bacteria can be advantageous in terms of biodiversity preservation, but non-QPS microorganisms can be included in the natural starter and also in cheeses, especially in traditional ones obtained from fermenting raw milk. Following EFSA guidelines, artisanal factories should not be allowed to produce starter cultures by themselves from raw milk, running the risk of including some non-QPS species in their culture, and only selected starters could be used for cheesemaking. A revision of the criteria of QPS guidelines should be necessary. Full article

Sheep are often utilized as a model ruminant, despite a lack of functional comparisons of rumen bacterial communities and responses during dietary transitions between sheep and cattle. Therefore, an ex vivo study was conducted to evaluate species differences. Rumen fluid was obtained from hay-fed sheep and cattle (n = 3 species⁻¹). Mixed bacterial cell suspensions in buffered media containing 3% w/v ground hay, corn, or combinations (2:1, 1:2) of substrates were incubated (24 h; 39 °C). Suspension pH, lactate, volatile fatty acids (VFA), and digestibility were assessed, functional guilds enumerated, and amylolytic bacteria isolated. Lactate was fully utilized in all hay incubations, and pH did not differ between species (p > 0.75). In contrast, digestibility, lactate accumulation, and pH decline were greater in bovine suspensions fermenting corn (p < 0.01). Streptococcus bovis was the predominant bacteria regardless of species, but total amylolytic bacteria were 10-fold greater in bovine suspensions (p < 0.01). Lactate-utilizing bacteria were 1000-fold greater in bovine than ovine suspensions (p < 0.01). However, total VFA did not differ between species (p > 0.28). Overall, these results demonstrate differential feed utilization capacities in rumen microbial communities of sheep and cattle as well as potential differences in rumen acidosis susceptibility. Full article

This study aimed to assess the influence of rice grain in the total mixed ration (TMR) on the growth performance, blood metabolites, rumen fermentation, and rumen microbial community of fattening Hanwoo steers. Two experimental diets were prepared: (i) a TMR containing 33% dry matter (DM) corn grains (Corn TMR) and (ii) a TMR containing 33% DM rice grains (Rice TMR). Twenty-two Hanwoo steers (body weight [BW], 498 ± 32 kg; months, 17 ± 0.5) were distributed into two treatment groups in a completely randomized block design according to BW. The Rice TMR group had a higher final BW and DM intake (DMI) compared to those in the Corn TMR group (p < 0.01). However, no difference was observed in the average daily gain (ADG) and feed conversion ratio (FCR) between the two treatments. For the rumen fermentation parameters, the molar portion of butyrate in the Rice TMR was higher than in the Corn TMR (p < 0.01). Streptococcus bovis tended to be higher in the Rice TMR (p = 0.09). The results of this study suggest that using rice grain as the primary starch source in TMRs may be an alternative option for fattening Hanwoo steers. Full article

In this study we evaluated the prevalence of pathogens detected via quantitative PCR (qPCR) in milk from apparently healthy cows to identify the most common etiological agents present in Italian dairy farms. Milk samples were collected using a sterile protocol at quarter-level (3239 samples, 822 cows) and a conventional protocol at udder level as composite milk from the functional quarters of each cow (5464 samples, 5464 cows). The qPCR commercial kit detected Mycoplasma bovis, Mycoplasma spp., Staphylococcus aureus, coagulase-negative staphylococci (CNS), Streptococcus agalactiae, Streptococcus dysgalactiae, Streptococcus uberis, Prototheca spp., Escherichia coli, Klebsiella spp., Enterococcus spp. and Lactococcus lactis ssp. lactis as well as DNA from the penicillin resistance β-lactamase gene from staphylococci. The prevalence of specific DNA was calculated based on its presence or absence in the samples, factoring in both the sampling protocols and herds. Regardless of the sampling protocol used, the most frequently detected pathogens were CNS (26.6% in sterile and 13.9% in conventional protocol) and Streptococcus uberis (9.6% and 16.5%, respectively). These results underscore the necessity for pathogen-specific interventions at the farm level to enhance the udder health of dairy cows via management recommendations. Full article

Microorganisms responsible for genitourinary infections increasingly include species other than conventional etiological agents that are of clinical and pathogenic relevance and therapeutic interest. This cross-sectional descriptive study selected samples from clinical genitourinary episodes between January 2016 and December 2019 in which emerging microbiological agents were detected. The patients’ epidemiological characteristics, clinical presentation, antibiotic treatment, and outcome were studied to identify their pathogenic role. The emerging microorganisms most frequently detected in urinary tract infections were Streptococcus bovis (58.5%) and Gardnerella spp. (23.6%) in females and S. bovis (32.3%), Aerococcus urinae (18.6%), and Corynebacterium spp. (16.9%) in males, while the most frequently detected in genital infections were S. viridans (36.4%) in females and C. glucuronolyticum (32.2%) and Gardnerella spp. (35.6%) in males. All cases in female children were produced by S. bovis. Symptomatic episodes were more frequent with Aerococcus spp. and S. bovis and the presence of leukocytosis more frequent with Aerococcus spp. Quinolones and doxycycline were most often prescribed antibiotics for genital infections and quinolones and amoxicillin-clavulanic acid for urinary infections. Urinary infection by Aerococcus spp. was more frequent in males of advanced age, Corynebacterium spp. was more frequent in permanent vesical catheter carriers, and episodes of asymptomatic bacteriuria by Gardnerella spp. were more frequent in patients with kidney transplant and chronic consumers of corticosteroid therapy. Lactobacillus spp. should be considered in urinary infections of patients of advanced age and with a previous antibiotic load. Genital infection by Gardnerella spp. was significantly associated with a history of risky sexual relations. Full article