Streptococcus Bovis Research Articles

1501 Double Whammy: Checkpoint Inhibitor and CMV-Induced Colitis

INTRODUCTION: Immune checkpoint inhibitors (ICIs) such as nivolumab have become a common treatment for several types of malignancies, especially metastatic disease. Diarrhea and enterocolitis are known side effects of these drugs. Here we present a case of a patient who developed ICI associated colitis who was later diagnosed with superimposed Cytomegalovirus colitis. CASE DESCRIPTION/METHODS: A 75-year-old male with past medical history pertinent for squamous cell carcinoma of the neck and base of tongue treated with nivolumab. His treatment was interrupted due to the development of chronic diarrhea possibly related to immune checkpoint inhibitor therapy (nivolumab). Immunotherapy was discontinued and the patient was started on a high dose of steroids with initial clinical response and symptom control. He was admitted to the hospital two months later with signs of shock with hematochezia and profound diarrhea. Computed Tomography (CT) of his abdomen upon admission showed severe colitis. Blood cultures were positive for Streptococcus infantarium (previously known as Streptococcus bovis) likely translocation from severe immunotherapy-induced colitis. His hemodynamics improved with fluid resuscitation and antibiotic therapy; however his diarrhea did not resolve. He then underwent colonoscopy which demonstrated circumferential, uninterrupted, extensive and severe inflammation (Figures 1 and 2) with the procedure terminated prematurely to avoid risk of perforation. Pathology of colonic biopsies showed positive immunostaining for Cytomegalovirus (CMV), and the patient tested positive for CMV DNA PCR, confirming acute active infection. He was started on valganciclovir and his steroid regimen was tapered with significant improvement of his diarrhea. DISCUSSION: Immune checkpoint inhibitors are monoclonal antibodies that target downregulators of the anti-neoplastic immune response. There are currently seven FDA approved ICIs, including Nivolumab. Immune-mediated colitis and diarrhea are the most common side effects associated with these drugs. One third of patients treated with ICIs will experience gastrointestinal adverse effects and 1-2% of patients on nivolumab will experience diarrhea. Although is not common, infection can coexist and in the setting of persistent and recurrent diarrhea it has to be ruled out.

3066 Recurrent Streptococcus bovis Bacteremia in the Absence of Colonic Neoplasm

INTRODUCTION: Associations between Streptococcus bovis (S. bovis) bacteremia and colorectal cancers and colonic adenomas have been reported in the medical literature since the 1970's. We are reporting an extremely rare case of recurrent Streptococcus bovis biotype II bacteremia in the absence of colonic neoplasm. CASE DESCRIPTION/METHODS: 53-year-old man with diffuse large B-cell lymphoma – in remission (treated with chemotherapy and autologous stem cell transplantation), nesidioblastosis (treated with partial pancreatectomy/splenectomy) and hypertension was admitted to the hospital with severe sepsis. Of note, one month prior to his presentation, he was admitted to the hospital for S. bovis bacteremia. Examination: temperature 37.8°C, HR 104/minute, respiratory rate 28/minute, BP 101/51 mmHg and Spo2 98% on 4 liters nasal cannula. Laboratory data: white cell count 32.83 × 103/μL, hemoglobin 13.0 g/dL, platelets 210 × 103/μL, sodium 139 mEq/L, potassium 3.2 mEq/L, chloride 95 mEq/L, bicarbonate 22.6 mEq/L, creatinine 1.3 mg/dL, AST 124 IU/L, ALT 152 IU/L, alkaline phosphatase 139 IU/L, total bilirubin 0.3 mg/dL, lactic acid 6.6 mmol/L. Blood culture – positive for S. bovis. Infective endocarditis was ruled out by an echocardiogram. Patient was given intravenous antibiotic therapy and follow up blood cultures did not demonstrate any growth. Due to the association between S. bovis bacteremia and colonic malignancy, colonoscopy was performed. Patient was found to have a small, hyperplastic polyp in the cecum and diverticulosis involving the ascending, sigmoid and descending colon. DISCUSSION: S. bovis is a rare cause of bacteremia accounting for <1% of blood culture isolates. It has a high mortality rate of 26-70% and has been associated with colorectal malignancy, endocarditis, and hepatic dysfunction. There are two S. bovis biotypes (I and II) and the prevalence of colorectal neoplasm in patients with S. bovis biotype II bacteremia (23%) is substantially lower than biotype I (70%). Our patient had S. bovis biotype II bacteremia and did not have evidence of malignancy/adenoma(s) in the colonoscopy. To our knowledge this is the first case of recurrent S. bovis bacteremia reported in the medical literature in the absence of both colorectal cancer and colonic adenoma.

An acute ischemic stroke presenting as rectal adenocarcinoma and streptococcus bovis endocarditis: A case report

An acute ischemic stroke presenting as rectal adenocarcinoma and streptococcus bovis endocarditis: A case report

Referral for Colonoscopy in Patients with Streptococcus bovis Bacteremia and the Association with Colorectal Cancer and Adenomatous Polyps: A Quality Assurance Study

The association between Streptococcus bovis (S. bovis) bacteremia and colorectal cancer is well established. We aimed to review patients with S. bovis bacteremia at our local hospital system and determine the percentage of patients referred for colonoscopy. Methods: We searched the regional database to identify S. bovis-positive blood cultures from 2002 to 2016 and the clinical characteristics and outcomes of those patients. Results: A total of 86 patients with S. bovis bacteremia were identified. From the 86 patients, 14 were excluded. The mean age of the 72 remaining patients was 74.5 (SD 13), 42/72 (58%) were male, 12/72 (17%) had infective endocarditis, and 19 (26%) died during admission. Of the 53 patients who survived, 37 (70%) were referred for colonoscopy or CT colonography, of which 30 had a colonoscopy. Thus, 3/30 (10%) cases showed adenocarcinoma and 11/30 (37%) cases showed adenomatous polyps. Age, gender, or the presence of infective endocarditis were not associated with adenocarcinoma or adenomatous polyps. Discussion: In our local centers, a significant proportion of patients with S. bovis were found to have colon cancer or significant polyps, and thus the importance of referral to colonoscopy remains paramount.

Administration of Streptococcus bovis isolated from sheep rumen digesta on rumen function and physiology as evaluated in a rumen simulation technique system.

Background and Aim:Little information about the stability and changes of sheep ruminal microbiota due to pathogen intervention in the rumen simulation technique (RUSITEC) is available. This study aimed to investigate the effect of administration of a novel isolated Streptococcus bovis strain on rumen microbiology and physiology. In addition, the isolation of pigment-producing Streptococcus lutetiensis is described.Materials and Methods:Microbial strains were isolated from sheep rumen digesta. An isolated strain of S. bovis was evaluated in the RUSITEC system fed with mixed cattle feed and compared with an in-house developed probiotic formulation (PF), PF 1, containing Bacillus amyloliquifaciens, Bacillus subtilis, and Propionibacterium freudenreichii. The parameters of volatile fatty acid, lactic acid, pH profiling, and the coliform anti-pathogenicity were evaluated to determine the effect of S. bovis on rumen function and physiology.Results:Administration of S. bovis reduced the coliform count by 31.20% from 7.2×1010 colony-forming units (CFU)/mLto 1.7×106 CFU/mL. Agar diffusion assays revealed the extracellular antimicrobial activity of S. bovis against coliforms; Escherichia coli and Salmonella enterica with 12 and 14 mm zones of inhibition, respectively. Simultaneously, an increase of 61.62% in the rumen yeast count was noted. The physiological changes resulted in a 5% reduction in acetic acid concentration from 431 to 405 mg/L.Conclusion:The present research indicates that S. bovis is highly capable of altering rumen physiology and function on colonization and is a key transition microbe to be studied during rumen intervention studies. A decrease in the coliform count could be attributed to extracellular production of a bacteriocin-like substance, as illustrated through agar diffusion assays.

20 Polyclonal antibody preparations from avian origin improves growth performance of beef cattle during the first fourteen days of the backgrounding phase

Abstract This study aimed to evaluate the effects of feeding avian-derived polyclonal antibody preparation (PAP; CAMAS, Inc.) against Streptococcus bovis, Fusobacterium necrophorum, and lipopolysaccharides (40, 35, and 25% of the preparation, respectively) on growth performance of beef cattle during the backgrounding phase. From d 0 to 56, Angus crossbreed heifers (n = 80; 360 ± 60 kg of BW; 470 ± 26 d of age) and steers (n = 20; 386 ± 65 kg of BW; 465 ± 30 d of age) were blocked by BW and randomly assigned to 1 of 16 concrete-floored pens (108 m2), equipped with 2 GrowSafe (GrowSafe Systems Ltd., Airdrie, Alberta, Canada) feed bunks each. Animals received a common ad libitum diet (76% TDN, 15.9% CP, DM basis) with the addition of 1 (PAP1), 3 (PAP3), or 0 g (CON) of PAP per d. Feed intake was recorded daily and BW were obtained on d -1, 0, 14, 28, 42, 55, and 56, to assess changes in BW, ADG, DMI, and G:F. Based upon orthogonal contrasts (CON vs. PAP1, and PAP1 vs. PAP3), BW and ADG on d 14, and DMI from 0 to 28, and 0 to 42 were greater for PAP1 vs. CON (P ≤ 0.03), whereas PAP3 animals were intermediate (P ≥ 0.20). No differences in final BW, DMI, and ADG from d 0 to 56 were detected among treatments (P ≥ 0.22). In conclusion, feeding 1g of polyclonal antibody preparations against Streptococcus bovis, Fusobacterium necrophorum, and lipopolysaccharides in a backgrounding diet, improved growth performance in the first 14 d of feeding suggesting that feeding these PAP for longer than 14 d may not be necessary. The effects on subsequent feedlot performance when using PAP should be evaluated in future studies

116 Polyclonal antibody preparations from avian origin improves growth performance of beef cattle during the first fourteen days of the backgrounding phase

Abstract This study aimed to evaluate the effects of feeding avian-derived polyclonal antibody preparation (PAP; CAMAS, Inc.) against Streptococcus bovis, Fusobacterium necrophorum, and lipopolysaccharides (40, 35, and 25% of the preparation, respectively) on growth performance of beef cattle during the backgrounding phase. From d 0 to 56, Angus crossbreed heifers (n = 80; 360 ± 60 kg of BW; 470 ± 26 d of age) and steers (n = 20; 386 ± 65 kg of BW; 465 ± 30 d of age) were blocked by BW and randomly assigned to 1 of 16 concrete-floored pens (108 m2), equipped with 2 GrowSafe (GrowSafe Systems Ltd., Airdrie, Alberta, Canada) feed bunks each. Animals received a common ad libitum diet (76% TDN, 15.9% CP, DM basis) with the addition of 1 (PAP1), 3 (PAP3), or 0 g (CON) of PAP per d. Feed intake was recorded daily and BW were obtained on d -1, 0, 14, 28, 42, 55, and 56, to assess changes in BW, ADG, DMI, and G:F. Based upon orthogonal contrasts (CON vs. PAP1, and PAP1 vs. PAP3), BW and ADG on d 14, and DMI from 0 to 28, and 0 to 42 were greater for PAP1 vs. CON (P ≤ 0.03), whereas PAP3 animals were intermediate (P ≥ 0.20). No differences in final BW, DMI, and ADG from d 0 to 56 were detected among treatments (P ≥ 0.22). In conclusion, feeding 1g of polyclonal antibody preparations against Streptococcus bovis, Fusobacterium necrophorum, and lipopolysaccharides in a backgrounding diet, improved growth performance in the first 14 d of feeding suggesting that feeding these PAP for longer than 14 d may not be necessary. The effects on subsequent feedlot performance when using PAP should be evaluated in future studies

Infective endocarditis in children: profile in a 6 years experience from Dr.Mohammad Hoesin Hospital, Palembang, Indonesia

Infective endocarditis (IE) is an inflammation or infection in the endocardium. Cardiac abnormalities represent a predisposing for the development of IE. The aim of this study is to describe the profile of IE from Mohammad Hoesin Hospital. A retrospective study was conducted from January 2011 to December 2017. Forty six children were diagnosed with IE, 67,4% of patients with aged > 5 years old. The nutritional status was 69.6% wasting and 30.4% normal. Congenital Heart Disease (CHD) was the predominant underlying heart condition (60,9%), followed by Rheumatic Heart Disease (RHD) 37% and without cardiac abnormalities (2,1%). The infective agents were identified in 50% cases, and the most frequent causative agents were Staphylococcus aureus (21.7%), followed by Staphylococcus epidermidis (10.9%), Streptococcus viridans (6.5%), Enterococcus faecalis (4.3%), Streptococcus bovis (1%), Staphylococcus haemoliticus (1%). The following complications were common: heart failure (65.2 %), pneumonia (17.4%), anemia (4.3%), pericardial effusion (4.3%) respectively.The most empirical antibiotics were ampicillin and gentamicin (82.6%) and only 1 patient underwent surgery for IE. The overall death was4.3%. The conclusion of this study is IE mostly occurs in CHD and the most organism is Staphylococcus aureus.

Heterologous gene expression in the human gut bacteria Eubacterium rectale and Roseburia inulinivorans by means of conjugative plasmids

Commensal butyrate-producing bacteria in the Firmicutes phylum are abundant in the human intestine and are important for maintaining health. However, understanding of the metabolism and host interaction of these bacteria is limited by the lack of genetic modification techniques. Here we establish a protocol enabling the transfer of autonomously-replicating shuttle vectors by conjugative plasmid transfer from an Escherichia coli donor into representatives of an important sub-group of strictly anaerobic human colonic Firmicutes. Five different plasmid shuttle vectors were tested, each carrying a different origin of replication from Gram-positive bacteria. Plasmid pMTL83151 (pCB102 replicon) were successfully transferred into two strains of Eubacterium rectale, while pMTL83151 and pMTL82151 (pBP1 replicon) were transferred into Roseburia inulinivorans A2-194. Plasmids that carried a Streptococcus bovis JB1 glycoside hydrolase family 16 β-(1,3-1,4)-glucanase gene were constructed and conjugated into Roseburia inulinivorans A2-194 and Eubacterium rectale T1-815, resulting in successful heterologous expression of this introduced enzymatic activity in these two strains of butyrate-producing Firmicutes.

First description of Streptococcus lutetiensis from a diseased cat.

This paper describes for the first time the isolation of Streptococcus lutetiensis in a cat with intestinal lymphoma. The Streptococcus bovis group has undergone significant taxonomic changes over the past two decades and, in 2002, Poyart et al. described two distinct novel species within the genus Streptococcus: Streptococcus lutetiensis and Streptococcus pasteurianus. The bovis group streptococci include commensal species and subspecies or opportunistic pathogens of humans and animals. The cat was referred to the Veterinary Teaching Hospital, University of Bologna for chronic diarrhoea associated with fresh blood. A diagnosis of intestinal lymphoma was advanced. S. lutetiensis was accidentally isolated from the faeces of the cat and identified through MALDI-TOF and 16s rRNA sequencing. The Kirby-Bauer test revealed that the isolate was resistant to enrofloxacin, erythromycin, clindamycin, marbofloxacin and tetracycline. The detection of S. lutetiensis in cat faeces might suggest that it could be a normal inhabitant of cat intestinal tract or that it could be involved in the manifestation of intestinal diseases. Since bacteria belonging to the S. bovis group are considered emerging pathogens, additional research is required to evaluate the role of S. lutetiensis in cats and its role in the transmission of antimicrobial resistance. SIGNIFICANCE AND IMPACT OF THE STUDY: In this study the isolation of Streptococcus lutetiensis from a cat with intestinal lymphoma was described for the first time. An antimicrobial susceptibility test performed by means of the disc diffusion method revealed that the isolate was resistant to enrofloxacin, erythromycin, clindamycin, marbofloxacin and tetracycline. Nowadays the ecological or pathogenetic role of S. lutetiensis in the gut of animals remains unclear but, even if its role as commensal bacterium was confirmed, the presence of multi-resistant S. lutetiensis in cat gut could favour the transmission of antimicrobial resistance to other bacteria.

Streptococcus bovis Endocarditis after Colonic Polypectomy.

We describe a case of Streptococcus lutetiensis infective endocarditis occurring in a patient following colonic polypectomy. The patient had multiple risk factors for infective endocarditis including pre-existing mitral valve prolapse and regurgitation. Transoesophageal echocardiography revealed a friable mass on the posterior mitral valve leaflet, confirming the diagnosis. The patient was treated with intravenous antibiotics, successfully underwent mitral valve surgery and was discharged home for outpatient follow-up.This report details an uncommon case presentation, highlights areas for improvement in clinical practice, and summarises the current knowledge available in the literature regarding Streptococcus bovis infective endocarditis.LEARNING POINTSInfective endocarditis occurring in association with gastrointestinal endoscopy is rare.Clinical suspicion of infective endocarditis after colonic polypectomy or biopsy should be maintained, especially in those with risk factors for infective endocarditis.Antibiotic prophylaxis against infective endocarditis is not recommended for routine gastrointestinal endoscopic procedures.

Differences in Fecal Gut Microbiota, Short-Chain Fatty Acids and Bile Acids Link Colorectal Cancer Risk to Dietary Changes Associated with Urbanization Among Zimbabweans

The incidence of colorectal cancer (CRC) is gradually rising in sub-Saharan Africa. This may be due to dietary changes associated with urbanization, which may induce tumor-promoting gut microbiota composition and function. We compared fecal microbiota composition and activity in 10 rural and 10 urban Zimbabweans for evidence of a differential CRC risk. Dietary intake was assessed by a food frequency questionnaire. Fecal microbiota composition, metabolomic profile, functional microbial genes were analyzed, and bile acids and short chain fatty acids quantified. Animal protein intake was higher among urban volunteers, but carbohydrate and fiber intake were similar. Bacteria related to Blautia obeum, Streptococcus bovis, and Subdoligranulum variabile were higher in urban residents, whereas bacteria related to Oscillospira guillermondii and Sporobacter termitidis were higher in rural volunteers. Fecal levels of primary bile acids, cholic acid, and chenodeoxycholic acid (P < 0.05), and secondary bile acids, deoxycholic acid (P < 0.05) and ursodeoxycholic acid (P < 0.001) were higher in urban residents. Fecal levels of acetate and propionate, but not butyrate, were higher in urban residents. The gut microbiota composition and activity among rural and urban Zimbabweans retain significant homogeneity (possibly due to retention of dietary fiber), but urban residents have subtle changes, which may indicate a higher CRC risk.

239 Streptococcus Bovis as the Source of Infection of an Arteriovenous Graft (AVG)

239 Streptococcus Bovis as the Source of Infection of an Arteriovenous Graft (AVG)

Bacterial Community Diversity Associated With Different Utilization Efficiencies of Nitrogen in the Gastrointestinal Tract of Goats.

The objective of this study was to examine the association between bacterial community structure and the utilization efficiency of nitrogen (UEN) phenotypes by determining the bacterial community in the gastrointestinal tract (GIT) of goats that differ in UEN using high-throughput 16S rRNA gene sequencing. Thirty Nubian goats were selected as experimental animals, and their UEN was determined in a metabolic experiment. Subsequently, eight individuals were grouped into the high nitrogen utilization (HNU) phenotype, and seven were grouped into the low nitrogen utilization (LNU) phenotype. The bacterial 16S rRNA gene amplicons from the rumen, abomasum, jejunum, cecum and colon contents of these animals were sequenced using next-generation high-throughput sequencing technology. Two hundred thirty-nine genera belonging to 23 phyla in the rumen, 319 genera belonging to 30 phyla in the abomasum, 248 genera belonging to 36 phyla in the jejunum, 248 genera belonging to 25 phyla in the colon and 246 genera belonging to 23 phyla in the cecum were detected, with Bacteroidetes and Firmicutes predominating. In addition, a significant correlation was observed between the UEN and the genera Succiniclasticum, Bacteroides, Ruminobacter, Methanimicrococcus, Mogibacterium, Eubacterium_hallii_group and Ruminococcus_1 in the rumen; Bacteroidales_S24-7_group, Bacteroidales_RF16_group, Bacteroidales_UCG-001 and Anaerovibrio in the abomasum; Ruminococcus_2, Candidatus_Saccharimonas, Candidatus_Arthromitus and Coprococcus_1 in the jejunum; Erysipelotrichaceae_UCG-004, Akkermansia, Senegalimassilia, Candidatus_Soleaferrea and Methanocorpusculum in the colon; and Ruminococcaceae_UCG-002, Anaerovibrio and Ruminococcaceae_UCG-007 in the cecum. Furthermore, the real-time PCR results showed that the ruminal copies of Fibrobacter_succinogenes, Butyrivibrio_fibrisolvens, Ruminococcus_sp._HUN007, Prevotella ruminicola and Streptococcus bovis in the HNU animals were significantly higher than those in the LNU animals. This study suggests an association of GIT microbial communities as a factor that influences UEN in goats.

Megasphaera elsdenii Lactate Degradation Pattern Shifts in Rumen Acidosis Models.

Background: Megasphaera elsdenii is an ecologically important rumen bacterium that metabolizes lactate and relieves rumen acidosis (RA) induced by a high-grain-diet. Understanding the regulatory mechanisms of the lactate metabolism of this species in RA conditions might contribute to developing dietary strategies to alleviate RA.Methods: Megasphaera elsdenii was co-cultured with four lactate producers (Streptococcus bovis, Lactobacilli fermentum, Butyrivibrio fibrisolvens, and Selenomonas ruminantium) and a series of substrate starch doses (1, 3, and 9 g/L) were used to induce one normal and two RA models (subacute rumen acidosis, SARA and acute rumen acidosis, ARA) under batch conditions. The associations between bacterial competition and the shift of organic acids’ (OA) accumulation patterns in both statics and dynamics manners were investigated in RA models. Furthermore, we examined the effects of substrate lactate concentration and pH on Megasphaera elsdenii’s lactate degradation pattern and genes related to the lactate utilizing pathways in the continuous culture.Results and Conclusion: The positive growth of M. elsdenii and B. fibrisolvens caused OA accumulation in the SARA model to shift from lactate to butyrate and resulted in pH recovery. Furthermore, both the quantities of substrate lactate and pH had remarkable effects on M. elsdenii lactate utilization due to the transcriptional regulation of metabolic genes, and the lactate utilization in M. elsdenii was more sensitive to pH changes than to the substrate lactate level. In addition, compared with associations based on statics data, associations discovered from dynamics data showed greater significance and gave additional explanations regarding the relationships between bacterial competition and OA accumulation.

Effects of replacing alfalfa hay with Moringa oleifera leaves and peduncles on intake, digestibility, and rumen fermentation in dairy cows

To study the effects of replacing alfalfa hay with Moringa oleifera leaves and peduncles in diets on intake, digestibility, and rumen fermentation in dairy cows, eight multiparous Holsteins cows with similar DIM (day in milk, 93 ± 18 d) and body weights (624 ± 38 kg) were used in a crossover design with two dietary treatments. The treatment diets contained similar concentrate mixtures and corn silage but different proportions of M. oleifera leaves and peduncles. The treatments were a (1) control diet (0% M. oleifera feed) and (2) M. oleifera diet (10.85% M. oleifera feed). The M. oleifera feed used M. oleifera leaves and M. oleifera peduncles at a ratio of 3:2 and replaced portions of alfalfa hay. The experimental period was 18 d, with 15 d for treatment adaptation and 3 d for data collection. Compared with the control diet, the dry matter intake and apparent digestibility of dry matter, crude protein, acid detergent fiber and neutral detergent fiber in the M. oleifera diet were significantly increased. No difference was observed in ruminal pH; however, the ammonia-N concentrate was lower for the M. oleifera diet than the control diet. The concentrations of total ruminal volatile fatty acids, acetate, propionate, and butyrate were higher in cows fed the M. oleifera diet than in those fed the control diet. The results of ruminal microbes showed that those consuming the M. oleifera diet had greater relative expression level of Fibrobacter succinogenes, Butyrivibrio fibrisolvens, Ruminobacter amylophilus, Streptococcus bovis, Prevotella ruminicola which were observed for the control diet than the M. oleifera diet. These results show that the M. oleifera diet can improve intake and apparent digestibility of nutrients, and rumen fermentation in dairy cows.

Bovicins: The Bacteriocins of Streptococci and Their Potential in Methane Mitigation.

Bovicin is a type AII lantibiotic, possessing two β-methyllanthionine and a disulfide bridge encoded by bovA gene hitherto unknown a couple of decades ago. Bacteriocins can be useful in directly inhibiting methanogens and/or redirecting H2 to other reductive microorganisms, in particular, propionate producers or reductive acetogens. So far, the role of nisin and bovicin to suppress greenhouse gas (GHG) production under in vitro conditions has been documented. GHG emissions from ruminants are a threat to the environment, because of their role in global warming as well as in climate change. Methane (CH4) produced from livestock farming practices is a potent GHG, comprising 18% of total GHG emissions in the world. Therefore, minimizing enteric CH4 production is quite essential from both the economical livestock production as well as environment perspectives. Strategies for the abatement of CH4 have provided two-way opportunities, viz., improved livestock productivity and reduced GHG emissions. In the past, different strategies have been proposed and tested to mitigate CH4, such as the dietary composition of feeds, ionophores, antibiotics, vaccines, analogues, probiotics, and secondary metabolites of plants and fungi. However, quite a few of these strategies have been adopted at farm level due to their varied effect on animal health and/or residues on animal products. The use of bacteriocins might have potential in inhibiting methanogens in the rumen. A bacteriocin produced by Streptococcus bovis (an isolate from rumen) named bovicin HC5 has been exhibited to decrease CH4 production to an extent of 50%. In this review, authors intend to discuss the sources, structure, biochemical properties, and antimicrobial spectra of bovicins, besides the potential applications with special reference to CH4 mitigation.

Streptococcus bovis as a Cause of Spontaneous Bacterial Peritonitis (SBP) and the Role of Colonoscopy

Streptococcus bovis as a Cause of Spontaneous Bacterial Peritonitis (SBP) and the Role of Colonoscopy

Polyclonal antibodies as a feed additive for cattle adapted or not adapted to highly fermentable carbohydrate diets

ABSTRACT The effect of a polyclonal antibody preparation (PAP) against Streptococcus bovis and Fusobacterium necrophorum on ruminal fermentation and digestion in ruminally cannulated cows was investigated in two 3 × 3 Latin squares in factorial arrangement of treatments 3 × 2 regarding two feed additives (PAP in powder (PAPP) and in liquid (PAPL) presentation) plus control (CON) and two managements of diets (with or without adaptation to highly fermentable carbohydrate diets). Adapted group had greater DMI (p < 0.0001) and DM (p < 0.0001), NDF (p = 0.03) and total carbohydrates (p < 0.0001) apparent digestibility when compared to non-adapted group. PAPL had greater DM (p = 0.02), NDF (p = 0.03) and total carbohydrates apparent digestibility when compared to PAPP or CON. Adapted animals had lower (p < 0.0001) rumen pH when compared to non-adapted animals. Moreover, PAPL group had greater (p = 0.04) rumen pH values when compared to PAPP and CON. PAPL showed potential effect as an additive by increasing apparent digestibility of DM, NDF and total carbohydrates and also for being more efficient to prevent the drop in rumen pH during the peak of fermentation.

Streptococcus bovis Group Bacteremia in the 21st Century

Introduction Advanced phenotypic, genomic, and proteomic laboratory techniques have recently modified Streptococcus bovis group (SBG) nomenclature. We wished to determine if physicians continue to recognize the importance of SBG and its association with gastrointestinal (GI) tract abnormalities and infective endocarditis amid the changes in microbiologic identification and nomenclature of these organisms. Methods We reviewed the medical records of adult patients (≥18 years of age) with positive blood cultures for SBG organisms admitted to our 510-bed teaching hospital from January 1, 2006, to December 31, 2017. We report the epidemiology, sources of bacteremia, comorbid conditions, courses of treatment, and the mortality for these patients. We also assess the hospital treatment team's (HTT's) knowledge of SBG nomenclature and of the associations of SBG bacteremia and underlying GI disease and infective endocarditis amid the changes in nomenclature of these organisms. Results There were 42 cases of SBG bacteremia during the 12-year study period: 22 in women (52.4%) and 20 in men (47.6%). Patient ages ranged from 51 to 96 years (mean age, 74.3 years; median age, 72.0 years). All but 2 patients had multiple comorbid conditions. Diabetes mellitus was the most common comorbidity. Colonoscopy was performed during hospitalization in 22 (52.5%) of 42 patients. The identifiable sources of bacteremia were as follows: lower GI tract in 19 patients (45.2%), upper GI tract in 5 patients (11.9%), Laennec cirrhosis in 3 patients (7.1%), and pancreatic disorders in 2 patients (4.6%). Eleven patients (26.2%) had primary bacteremia. Two patients with primary bacteremia had prior splenectomy. The historic association between SBG bacteremia and underlying GI tract disease was recognized by 37 (88.1%) of 42 HTTs, but all available provider progress notes mention only “colon carcinoma” as the possibly associated GI tract pathology. The historic association of SBG bacteremia with infective endocarditis was recognized in writing by 32 (76.2%) of 42 HTTs. Endocarditis was diagnosed in 12 patients (28.6%): 9 definite endocarditis and 3 possible endocarditis. The mitral valve was the most commonly involved valve. Four SBG isolates were intermediately susceptible to penicillin G with minimum inhibitory concentrations of 0.125 μg/mL or greater. Twenty-three (54.8%) of 42 SBG strains were resistant or intermediately susceptible to clindamycin. Twenty-four (57.1%) of 42 strains were resistant or intermediately susceptible to erythromycin. All strains were tested for susceptibility to ceftriaxone and vancomycin and retained susceptibility to both antimicrobial agents throughout the study period. Six of 42 patients died, for a mortality rate of 11.9%. Infectious disease consultation was obtained in 35 (80.0%) of 42 patients. Infectious disease consultation was positively associated with survival (P = 0.0041, Fisher exact test). The new nomenclature schemes for prior members of the SBG were recognized by all HTTs because our microbiology laboratory reported each member of the group, regardless of new name, with “bovis group” added to the identification on all positive culture reports. Conclusions Streptococcus bovis group bacteremia is a disease of older adults with all but 3 patients 60 years or older and a mean age at onset of 73.4 years. Most HTTs considered colon carcinoma as a possible source for and infective endocarditis as a potential complication of SBG bacteremia. However, most HTTs were not aware that SBG bacteremia could be associated with nonmalignant colonic lesions especially polyps, Laennec cirrhosis, or with pancreatic, biliary, and upper GI tract anatomic abnormalities. Of our SBG isolates, 54.8% were not sensitive to clindamycin. Clindamycin should not be used for empiric treatment of SBG bacteremia. The ID service should be consulted on all patients with SBG bacteremia because such consultation had a positive correlation with patient survival (P = 0.0041).