ABSTRACT
INTRODUCTION: Up to 90% of patients undergo inadequate resection for incidentally diagnosed T1b-T3 gallbladder cancer (GBC). We evaluated whether adjuvant therapies (ATs) are associated with prolonged overall survival (OS) for patients undergoing inadequate resection of T1b-T3 GBC. METHODS: Patients who underwent inadequate resection, defined as simple cholecystectomy, for T1b-T3, Nx-N2, and M0 GBC were identified from the National Cancer Database (2004-2016). Patient characteristics, variables associated with AT use, and OS were described using the chi-square test, multivariable logistical regression, Kaplan-Meier, and Cox proportional hazard models. RESULTS: Of 1386 patients who met inclusion criteria, most received no AT (64%), 20% received chemotherapy (CT), and 16% received chemoradiotherapy (CRT). Patients who received no AT were generally older (51% ≥ 75 y) and had no comorbidities (65% Charlson Comorbidity Index 0). Among those who received AT, CRT rather than CT, tended to be employed for patients who were older (≥75 y) or had more comorbidities (Charlson Comorbidity Index ≥1). Patients with advanced disease (T3, positive lymph nodes, or positive margins) were more likely to receive CRT. For T1b-T3 GBC, any AT was associated with prolonged median OS compared to no AT (22 months versus 15 mo, P < 0.01). Relative to no AT, CT (hazard ratio 0.76, 95% confidence interval 0.67-0.92) and CRT (0.59, 95% confidence interval 0.49-0.72) were associated with decreased risk of death. CONCLUSIONS: AT was associated with prolonged OS for patients with inadequately resected T1b-T3 GBC. CRT may have a role in treatment for patients with high-risk disease following inadequate resection of T1b-T3 GBC.
ABSTRACT
PURPOSE: Patients undergoing oncologic surgery at major referral centers frequently experience postdischarge care fragmentation, which has been associated with poor outcomes. This report describes and evaluates the outcomes of an intervention at Memorial Sloan Kettering Cancer Center (MSKCC) to decentralize postdischarge postoperative acute care within our health care system. METHODS: In 2018, MSKCC completed the addition of six regional acute care clinics called symptom care clinics (SCCs) to existing regional outpatient clinics. Acute care was previously only available within our system at a single centralized urgent care center (UCC). All patients undergoing surgery in our system between January 1, 2019, and June 30, 2021, were followed for 90 days. The exposure was the site of initial acute care presentation-UCC or SCC-and outcomes included utilization, access, financial toxicity, and mortality. Mortality was adjusted using hierarchical modeling at the level of the region. RESULTS: A total of 6,992 postsurgical patients experienced 10,525 acute care visits in our system within 90 days of surgery. Twenty-nine percent of these patients presented to the SCC first. These patients were older but had fewer comorbidities and shorter index length of stay compared with UCC patients. Utilization of SCCs increased substantially while UCC utilization decreased during a period of stable case volume. SCCs were closer to patients' homes, and wait times were shorter. Rates of financial toxicity were similar between groups. Of this high-risk cohort accessing acute care postoperatively, 90-day mortality was similar for UCC and SCC patients (P = .731). CONCLUSION: This model of decentralized acute care after oncologic surgery was increasingly used over time with comparable patient safety. Health systems should emphasize patient-centered care by supporting safe strategies for regionalized care even when treatments are delivered at centralized referral centers.
Subject(s)
Postoperative Care , Humans , Male , Female , Middle Aged , Neoplasms/surgery , Aged , Delivery of Health CareABSTRACT
PURPOSE: The ACOSOG Z0011 (Z11) trial assessed the benefit of axillary dissection (ALND) for breast cancer patients with sentinel lymph node (SLN) metastases; however, Z11 excluded patients with ≥ 3 positive SLNs. We analyzed trends in ALND omission in patients with ≥ 3 positive SLNs. METHODS: Women with ≥ 3 positive SLNs who underwent breast-conserving surgery (BCS) or mastectomy between 2018 and 2020 in the National Cancer Database were included using SLN codes initiated in 2018. Patients with stage IV disease, recurrent breast cancer, and who underwent neoadjuvant chemotherapy were excluded. A multivariable logistic regression model was utilized to determine the proportion who received ALND and factors associated with ALND omission. A subgroup analysis was performed among patients who met the remainder of the Z11 inclusion criteria (BCS, T1/T2 breast cancer). RESULTS: We identified 3654 patients with ≥ 3 positive SLNs. ALND was omitted in 37% of patients, and omission significantly increased from 2018 to 2020 (29% vs. 41%, p < 0.0001). Older age, lower grade tumors, no radiation, non-academic facility, BCS, more SLNs examined and fewer positive SLNs were significantly associated with ALND omission. 942 patients with ≥ 3 positive SLNs met the remainder of the Z11 inclusion criteria. ALND was omitted in 49% of these patients, and omission increased from 2018 to 2020 (44% vs. 49%, p = 0.22). CONCLUSION: Approximately one-third of patients with ≥ 3 positive SLNs do not undergo ALND; omission of ALND increased from 2018 to 2020. Studies assessing oncologic outcomes of patients with ≥ 3 positive SLNs who do and do not receive ALND are required.
Subject(s)
Axilla , Breast Neoplasms , Lymph Node Excision , Sentinel Lymph Node Biopsy , Sentinel Lymph Node , Humans , Female , Breast Neoplasms/pathology , Breast Neoplasms/surgery , Middle Aged , Sentinel Lymph Node/pathology , Sentinel Lymph Node/surgery , Lymph Node Excision/methods , Aged , Sentinel Lymph Node Biopsy/methods , Adult , Lymphatic Metastasis , Mastectomy, Segmental/methods , Mastectomy/methods , Retrospective StudiesSubject(s)
Income , Pancreatic Neoplasms , Humans , Socioeconomic Factors , Pancreatic Neoplasms/surgeryABSTRACT
Microwave ablation of liver tumors allows preservation of liver parenchyma with good oncologic outcomes. However, ablation of tumors in the caudate lobe is particularly challenging. Adjacent critical anatomy, particularly the biliary hilum, has led to caudate location being considered a relative contraindication to ablation. To date, no series have described laparoscopic microwave ablation of caudate tumors of the liver. We describe our early experience with laparoscopic microwave ablation of caudate tumors. In this retrospective review of a prospectively maintained single-institution database, six patients with six primary or secondary caudate tumors underwent laparoscopic microwave ablation with no complications. At a median follow-up of 10.5 months, five out of six patients are free of caudate recurrence. Laparoscopic microwave ablation of caudate tumors is feasible. Long-term follow-up is needed to determine if local recurrence risk is higher than in other anatomical segments.
ABSTRACT
The surgical management of primary and secondary liver tumors is constantly evolving. Patient selection, particularly with regard to determining resectability, is vital to the success of programs directed toward invasive treatments of liver tumors. Particular attention should be paid toward determining whether patients are best served with surgical resection or ablative therapies. A multidisciplinary approach is necessary to provide optimal care to patients with liver malignancy.
ABSTRACT
Malnutrition (MN) is a common primary or secondary complication in gastrointestinal diseases. The patient's nutritional status also influences muscle mass and function, which can be impaired up to the degree of sarcopenia. The molecular interactions in diseases leading to sarcopenia are complex and multifaceted, affecting muscle physiology, the intestine (nutrition), and the liver at different levels. Although extensive knowledge of individual molecular factors is available, their regulatory interplay is not yet fully understood. A comprehensive overall picture of pathological mechanisms and resulting phenotypes is lacking. In silico approaches that convert existing knowledge into computationally readable formats can help unravel mechanisms, underlying such complex molecular processes. From public literature, we manually compiled experimental evidence for molecular interactions involved in the development of sarcopenia into a knowledge base, referred to as the Sarcopenia Map. We integrated two diseases, namely liver cirrhosis (LC), and intestinal dysfunction, by considering their effects on nutrition and blood secretome. We demonstrate the performance of our model by successfully simulating the impact of changing dietary frequency, glycogen storage capacity, and disease severity on the carbohydrate and muscle systems. We present the Sarcopenia Map as a publicly available, open-source, and interactive online resource, that links gastrointestinal diseases, MN, and sarcopenia. The map provides tools that allow users to explore the information on the map and perform in silico simulations.
ABSTRACT
Objective: Obesity, often associated with non-alcoholic fatty liver disease (NAFLD), is characterized by an imbalance between energy expenditure and food intake, which is also reflected by desensitization of fibroblast growth factor 21 (FGF21). FGF21 is strongly influenced, among others, by TNFα, which is known to be upregulated in obesity-induced inflammation. Successful long-term treatments of NAFLD might be dietary modification, exercise, or fasting. Materials and methods: Whether succeeded NAFLD recovery is linked with improved FGF21 sensitivity and finally reverted FGF21 resistance was the focus of the present study. For this purpose, mice received a high-fat diet (HFD) for 6 months to establish obesity. Afterward, the mice were subjected to three different weight loss interventions, namely, dietary change to low-fat diet (LFD), treadmill training, and/or time-restricted feeding for additional 6 months, whereas one group remained on HFD. Results: In addition to the expected decrease in NAFLD activity with dietary change, this was also observed in the HFD group with additional time-restricted feeding. There was also an associated decrease in hepatic TNFα and FGF21 expression and an increase in ß-klotho expression, demonstrated mainly by using principal component analysis. Pearson correlation analysis shows that independent of any intervention, TNFα expression decreased with improved NAFLD recovery. This was accompanied with higher FGF21 sensitivity, as expressed by an increase in ß-klotho and FGFR1c expression and concomitantly decreased FGF21 levels. Conclusion: In summary, we conclude that successful NAFLD therapy is associated with a reversion of the TNFα-triggered FGF21-resistant state or desensitization.
ABSTRACT
Seaweeds are macroalgae, which can be of many different morphologies, sizes, colors, and chemical profiles. They include brown, red, and green seaweeds. Brown seaweeds have been more investigated and exploited in comparison to other seaweed types for their use in animal feeding studies due to their large sizes and ease of harvesting. Recent in vitro and in vivo studies suggest that plant secondary compound-containing seaweeds (e.g., halogenated compounds, phlorotannins, etc.) have the potential to mitigate enteric methane (CH4) emissions from ruminants when added to the diets of beef and dairy cattle. Red seaweeds including Asparagopsis spp. are rich in crude protein and halogenated compounds compared to brown and green seaweeds. When halogenated-containing red seaweeds are used as the active ingredient in ruminant diets, bromoform concentration can be used as an indicator of anti-methanogenic properties. Phlorotannin-containing brown seaweed has also the potential to decrease CH4 production. However, numerous studies examined the possible anti-methanogenic effects of marine seaweeds with inconsistent results. This work reviews existing data associated with seaweeds and in vitro and in vivo rumen fermentation, animal performance, and enteric CH4 emissions in ruminants. Increased understanding of the seaweed supplementation related to rumen fermentation and its effect on animal performance and CH4 emissions in ruminants may lead to novel strategies aimed at reducing greenhouse gas emissions while improving animal productivity.
ABSTRACT
Obesity is one of the most challenging diseases of the 21st century and is accompanied by behavioural disorders. Exercise, dietary adjustments, or time-restricted feeding are the only successful long-term treatments to date. Fibroblast growth factor 21 (FGF21) plays a key role in dietary regulation, but FGF21 resistance is prevalent in obesity. The aim of this study was to investigate in obese mice whether weight reduction leads to improved behaviour and whether these behavioural changes are associated with decreased plasma FGF21 levels. After establishing a model for diet-induced obesity, mice were subjected to three different interventions for weight reduction, namely dietary change, treadmill exercise, or time-restricted feeding. In this study, we demonstrated that only the combination of dietary change and treadmill exercise affected all parameters leading to a reduction in weight, fat, and FGF21, as well as less anxious behaviour, higher overall activity, and improved olfactory detection abilities. To investigate the interrelationship between FGF21 and behavioural parameters, feature selection algorithms were applied designating FGF21 and body weight as one of five highly weighted features. In conclusion, we concluded from the complementary methods that FGF21 can be considered as a potential biomarker for improved behaviour in obese mice after weight reduction.
Subject(s)
Fibroblast Growth Factors/blood , Locomotion , Obesity/blood , Smell , Weight Loss , Animals , Biomarkers/blood , Diet, High-Fat , Elevated Plus Maze Test , Fasting , Female , Fibroblast Growth Factors/metabolism , Humans , Machine Learning , Mice , Mice, Inbred C57BL , Mice, Obese , Open Field Test , Physical Conditioning, AnimalABSTRACT
Animal manure can be a source of antibiotic-resistant genes (ARGs) and pharmaceutical residues; however, few studies have evaluated the presence of ARG in pasture-raised animal production systems. The objective of this study was to examine changes in microbiome diversity and the presence of antibiotic residues (ABRs) on three farms that contained a diverse range of animal species: pasture-raised poultry (broiler and layer), swine, and beef cattle. Total bacterial communities were determined using 16S rRNA microbiome analysis, while specific ARGs (sulfonamide [Sul; Sul1] and tetracycline [Tet; TetA]) were enumerated by qPCR (real-time PCR). Results indicated that the ARG abundances (Sul1 [P < 0.05] and TetA [P < 0.001]) were higher in layer hen manures (16.5 × 10-4 and 1.4 × 10-4 µg kg-1, respectively) followed by broiler chickens (2.9 × 10-4 and 1.7 × 10-4 µg kg-1, respectively), swine (0.22 × 10-4 and 0.20 × 10-4 µg kg-1, respectively) and beef cattle (0.19 × 10-4 and 0.02 × 10-4 µg kg-1, respectively). Average fecal TetA ABR tended to be greater (P = 0.09) for broiler chickens (11.4 µg kg-1) than for other animal species (1.8 to 0.06 µg kg-1), while chlortetracycline, lincomycin, and oxytetracycline ABRs were similar among animal species. Furthermore, fecal microbial richness and abundances differed significantly (P < 0.01) both among farms and specific species of animal. This study indicated that the microbial diversity, ABR, ARG concentrations, and types in feces varied from farm-to-farm and from animal species-to-animal species. Future studies are necessary to perform detailed investigations of the horizontal transfer mechanism of antibiotic-resistant microorganisms (ARMs) and ARG.
Subject(s)
Manure , Poultry , Animals , Anti-Bacterial Agents/pharmacology , Cattle , Chickens , Drug Resistance, Microbial , Female , Genes, Bacterial , RNA, Ribosomal, 16S/genetics , Soil , SwineABSTRACT
BACKGROUND: Hepatopancreatobiliary (HPB) and gastric oncologic operations are frequently performed at referral centers. Postoperatively, many patients experience care fragmentation, including readmission to "outside hospitals" (OSH), which is associated with increased mortality. Little is known about patient-level and hospital-level variables associated with this mortality difference. STUDY DESIGN: Patients undergoing HPB or gastric oncologic surgery were identified from select states within the Healthcare Cost and Utilization Project database (2006-2014). Follow-up was 90 days after discharge. Analyses used Kruskal-Wallis test, Youden index, and multilevel modeling at the hospital level. RESULTS: There were 7,536 patients readmitted within 90 days of HPB or gastric oncologic surgery to 636 hospitals; 28% of readmissions (n = 2,123) were to an OSH, where 90-day readmission mortality was significantly higher: 8.0% vs 5.4% (p < 0.01). Patients readmitted to an OSH lived farther from the index surgical hospital (median 24 miles vs 10 miles; p < 0.01) and were readmitted later (median 25 days after discharge vs 12; p < 0.01). These variables were not associated with readmission mortality. Surgical complications managed at an OSH were associated with greater readmission mortality: 8.4% vs 5.7% (p < 0.01). Hospitals with <100 annual HPB and gastric operations for benign or malignant indications had higher readmission mortality (6.4% vs 4.7%, p = 0.01), although this was not significant after risk-adjustment (p = 0.226). CONCLUSIONS: For readmissions after HPB and gastric oncologic surgery, travel distance and timing are major determinants of care fragmentation. However, these variables are not associated with mortality, nor is annual hospital surgical volume after risk-adjustment. This information could be used to determine safe sites of care for readmissions after HPB and gastric surgery. Further analysis is needed to explore the relationship between complications, the site of care, and readmission mortality.
Subject(s)
Continuity of Patient Care/organization & administration , Digestive System Neoplasms/therapy , Digestive System Surgical Procedures/adverse effects , Patient Readmission/statistics & numerical data , Postoperative Complications/epidemiology , Aged , Chemotherapy, Adjuvant/economics , Chemotherapy, Adjuvant/statistics & numerical data , Continuity of Patient Care/economics , Continuity of Patient Care/statistics & numerical data , Databases, Factual/statistics & numerical data , Digestive System Neoplasms/economics , Digestive System Neoplasms/mortality , Digestive System Surgical Procedures/economics , Digestive System Surgical Procedures/statistics & numerical data , Female , Health Care Costs/statistics & numerical data , Hospital Mortality , Humans , Male , Middle Aged , Patient Acceptance of Health Care/statistics & numerical data , Patient Readmission/economics , Postoperative Complications/economics , Postoperative Complications/etiology , Radiotherapy, Adjuvant/economics , Radiotherapy, Adjuvant/statistics & numerical data , Retrospective Studies , Risk Assessment/statistics & numerical data , Risk Factors , Tertiary Care Centers/economics , Tertiary Care Centers/organization & administration , Tertiary Care Centers/statistics & numerical data , Time FactorsABSTRACT
INTRODUCTION: Hepatoblastoma (HB) is a rare childhood malignancy with hepatic resection (HR) or liver transplantation (LT) providing the best chance of cure. In this study, we analyze the National Cancer Database lacks (NCDB) to compare outcomes following HR and LT for HB. METHODS: Review of the US experience with surgical (HR and LT) management of pediatric (< 18 years) HB over the last decade (2004-2014) using data extracted from the NCDB. RESULTS: A total of 628 children underwent surgical treatment for HB during the study period: HR in 525 (83.6%) and LT in 103 (16.4%). The two groups were comparable for age, sex, race, tumor size, and metastatic disease at initial diagnosis. LT group had significantly higher number of patients with bilobar disease (40 vs 21%; p < 0.001), longer median time from diagnosis to surgery (120 vs 78 days; p < 0.001), and longer post-operative length of stay (LOS) (14 vs 6 days; p < 0.001). There were no differences in rates of 30-day readmission and 30- or 90-day mortality between groups. Both groups had comparable 5-year overall survival (OS) (84.1% HR vs 80.0% LT; p = 0.4). Univariate analysis identified metastatic disease at initial presentation (HR 2.56, CI 1.51-4.35) and age ≥ 4 years (HR 2.68, CI 1.5-4.7) as risk factors for worse overall 5-yr OS, while administration of adjuvant chemotherapy was associated with improved 5-yr OS (92.3% with chemo vs 85.4% without chemo; HR 0.51, CI 0.31-0.84). CONCLUSION: The outcome of HB has improved compared with historical controls. Age at presentation, metastatic disease, and post-operative chemotherapy impact outcomes.
Subject(s)
Hepatoblastoma/epidemiology , Hepatoblastoma/surgery , Liver Neoplasms/epidemiology , Liver Neoplasms/surgery , Adolescent , Chemotherapy, Adjuvant , Child , Child, Preschool , Hepatoblastoma/pathology , Humans , Infant , Liver Neoplasms/pathology , Liver Transplantation/mortality , Liver Transplantation/statistics & numerical data , Male , National Cancer Institute (U.S.) , Neoplasm Metastasis , Risk Factors , SEER Program , Survival Analysis , Treatment Outcome , United States/epidemiologyABSTRACT
Methane gas from livestock production activities is a significant source of greenhouse gas (GHG) emissions which have been shown to influence climate change. New technologies offer a potential to manipulate the rumen biome through genetic selection reducing CH4 production. Methane production may also be mitigated to varying degrees by various dietary intervention strategies. Strategies to reduce GHG emissions need to be developed which increase ruminant production efficiency whereas reducing production of CH4 from cattle, sheep, and goats. Methane emissions may be efficiently mitigated by manipulation of natural ruminal microbiota with various dietary interventions and animal production efficiency improved. Although some CH4 abatement strategies have shown efficacy in vivo, more research is required to make any of these approaches pertinent to modern animal production systems. The objective of this review is to explain how anti-methanogenic compounds (e.g., plant tannins) affect ruminal microbiota, reduce CH4 emission, and the effects on host responses. Thus, this review provides information relevant to understanding the impact of tannins on methanogenesis, which may provide a cost-effective means to reduce enteric CH4 production and the influence of ruminant animals on global GHG emissions.
ABSTRACT
The Publisher regrets that this article is an accidental duplication of an article that has already been published, https://doi.org/10.1016/j.mam.2020.100894. The duplicate article has therefore been withdrawn. The full Elsevier Policy on Article Withdrawal can be found at https://www.elsevier.com/about/our-business/policies/article-withdrawal.
ABSTRACT
Acute inflammation is a protective reaction by the immune system in response to invading pathogens or tissue damage. Ideally, the response should be localized, self-limited, and returning to homeostasis. If not resolved, acute inflammation can result in organ pathologies leading to chronic inflammatory phenotypes. Acute inflammation and inflammation resolution are complex coordinated processes, involving a number of cell types, interacting in space and time. The biomolecular complexity and the fact that several biomedical fields are involved, make a multi- and interdisciplinary approach necessary. The Atlas of Inflammation Resolution (AIR) is a web-based resource capturing an essential part of the state-of-the-art in acute inflammation and inflammation resolution research. The AIR provides an interface for users to search thousands of interactions, arranged in inter-connected multi-layers of process diagrams, covering a wide range of clinically relevant phenotypes. By mapping experimental data onto the AIR, it can be used to elucidate drug action as well as molecular mechanisms underlying different disease phenotypes. For the visualization and exploration of information, the AIR uses the Minerva platform, which is a well-established tool for the presentation of disease maps. The molecular details of the AIR are encoded using international standards. The AIR was created as a freely accessible resource, supporting research and education in the fields of acute inflammation and inflammation resolution. The AIR connects research communities, facilitates clinical decision making, and supports research scientists in the formulation and validation of hypotheses. The AIR is accessible through https://air.bio.informatik.uni-rostock.de.
Subject(s)
Inflammation Mediators , Inflammation , Homeostasis , HumansABSTRACT
The goal of this pilot study was to track patient outcomes after an expedited discharge after enhanced recovery after surgery (ERAS) pathway for pancreaticoduodenectomy (PD). A quantitative content analysis approach was used. All PD patients in a single academic medical center between February 2017 and June 2018 were called twice by specialized physician extenders after discharge. A semi-structured interview approach was used to identify patient's symptoms or concerns, proactively educate them, and provide outpatient management when indicated. A detailed narrative of the conversation was documented. Ninety patients (mean age 66.3; 58.1% males) were included in the study. Of all, 88.9 per cent of the patients received follow-up phone calls in accordance with our PD ERAS protocol. Among the 80 patients called, 71 (88.8%) reported at least one symptom, issue, or self-care need. The most common issues involved bowel movements and nutrition. A total of 147 interventions were performed to address patient needs including medication management, local care coordination, and outpatient referral to a healthcare provider. The intervention led to the identification of 15 patients for earlier evaluation. This identification was associated with the total number of reported symptoms (X² = 15.6, P = 0.004). Most patients require additional care after discharge after traditional ERAS pathways. ERAS transitional care protocols uncovered an unmet need for additional patient support after PD.
Subject(s)
Enhanced Recovery After Surgery/standards , Pancreaticoduodenectomy , Patient Discharge , Telephone , Aged , Clinical Protocols , Female , Humans , Length of Stay , Male , Patient Education as Topic , Pilot Projects , Postoperative Complications/prevention & controlABSTRACT
Two sets of in vitro rumen fermentation experiments were conducted to determine effects of diets that included wet distiller's grains plus solubles (WDGS) and tannin-rich peanut skin (PS) on the in vitro digestibility, greenhouse gas (GHG) and other gas emissions, fermentation rate, and microbial changes. The objectives were to assess associative effects of various levels of PS or WDGS on the in vitro digestibility, GHG and other gas emissions, fermentation rate, and microbial changes in the rumen. All gases were collected using an ANKOM Gas Production system for methane (CH4), carbon dioxide (CO2), nitrous oxide (N2O), and hydrogen sulfide (H2S) analyses. Cumulative ruminal gas production was determined using 250 mL ANKOM sampling bottles containing 50 mL of ruminal fluid (pH 5.8), 40 mL of artificial saliva (pH 6.8), and 6 g of mixed diets after a maximum of 24 h of incubation. Fermenters were flushed with CO2 gas and held at 39 °C in a shaking incubator for 24 h. Triplicate quantitative real-time polymerase chain reaction (qPCR) analyses were conducted to determine microbial diversity. When WDGS was supplied in the diet, in the absence of PS, cumulative CH4 production increased (P < 0.05) with 40% WDGS. In the presence of PS, production of CH4 was reduced but the reduction was less at 40% WDGS. In the presence of PS, ruminal lactate, succinate, and acetate/propionate (A/P) ratio tended to be less with a WDGS interaction (P < 0.01). In the presence of PS and with 40% WDGS, average populations of Bacteroidetes, total methanogens, Methanobrevibacter sp. AbM4, and total protozoa were less. The population of total methanogens (R2 = 0.57; P < 0.01), Firmicutes (R2 = 0.46: P < 0.05), and Firmicutes/Bacteroidetes (F/B) ratio (R2 = 0.46; P < 0.03) were strongly correlated with ruminal CH4 production. Therefore, there was an associative effect of tannin-rich PS and WDGS, which suppressed methanogenesis both directly and indirectly by modifying populations of ruminal methanogens.