Risk factors for collisions attributed to microsleep-related behaviors while driving in professional truck drivers.

Sleep-disordered breathing (SDB) is prevalent among professional drivers. Although SDB is a known risk factor for truck collisions attributed to microsleep-related behaviors at the wheel (TC-MRBs), the usefulness of overnight pulse oximetry for predicting TC-MRBs is debatable. This retrospective study assessed the association between overnight pulse oximetry parameters, the Epworth Sleepiness Scale (ESS), and TC-MRBs, confirmed by dashcam footage. This study included 108 matched professional truck drivers (TC-MRBs: N = 54; non-TC-MRBs: N = 54), with a mean age and body mass index of 41.9 ± 11.3 years and 23.0 ± 3.7 kg/m2, respectively. Night-time drivers, 4% oxygen desaturation index (ODI), and nadir oxygen saturation (SpO2) were associated with TC-MRBs (odds ratio [95% confidence interval]: 25.63 [5.88-111.77], p < 0.0001; 2.74 [1.02-7.33], p = 0.045; and 3.87 [1.04-14.39], p = 0.04, respectively). The area under the curve of 4% ODI and nadir SpO2 for TC-MRBs were 0.50 and 0.57, respectively. In conclusion, night-time driving, 4% ODI, and nadir SpO2 were significantly associated with TC-MRBs in professional truck drivers. However, the sensitivity of overnight pulse oximetry parameters to predict TC-MRBs in a real-world application was poor. Therefore, combining subjective and objective assessments such as dashcam video footage may be needed to achieve high accuracy for predicting TC-MRBs among professional truck drivers.

A rumen virosphere with implications of contribution to fermentation and methane production, and endemism in cattle breeds and individuals.

Viruses have a potential to modify the ruminal digestion via infection and cell lysis of prokaryotes, suggesting that viruses are related to animal performance and methane production. This study aimed to elucidate the genome-based diversity of rumen viral communities and the differences in virus structure between individuals and cattle breeds and to understand how viruses influence on the rumen. To these ends, a metagenomic sequencing of virus-like particles in the rumen of 22 Japanese cattle, including Japanese Black (JB, n = 8), Japanese Shorthorn (n = 2), and Japanese Black sires × Holstein dams crossbred steers (F1, n = 12) was conducted. Additionally, the rumen viromes of six JB and six F1 that were fed identical diets and kept in a single barn were compared. A total of 8,232 non-redundant viral genomes (≥5-kb length and ≥50% completeness), including 982 complete genomes, were constructed, and rumen virome exhibited lysogenic signatures. Furthermore, putative hosts of 1,223 viral genomes were predicted using tRNA and clustered regularly interspaced short palindromic repeat (CRISPR)-spacer matching. The genomes included 1 and 10 putative novel complete genomes associated with Fibrobacter and Ruminococcus, respectively, which are the main rumen cellulose-degrading bacteria. Additionally, the hosts of 22 viral genomes, including 2 complete genomes, were predicted as methanogens, such as Methanobrevibacter and Methanomethylophilus. Most rumen viruses were highly rumen and individual specific and related to rumen-specific prokaryotes. Furthermore, the rumen viral community structure was significantly different between JB and F1 steers, indicating that cattle breed is one of the factors influencing the rumen virome composition.IMPORTANCEHere, we investigated the individual and breed differences of the rumen viral community in Japanese cattle. In the process, we reconstructed putative novel complete viral genomes related to rumen fiber-degrading bacteria and methanogen. The finding strongly suggests that rumen viruses contribute to cellulose and hemicellulose digestion and methanogenesis. Notably, this study also found that rumen viruses are highly rumen and individual specific, suggesting that rumen viruses may not be transmitted through environmental exposure. More importantly, we revealed differences of viral communities between JB and F1 cattle, indicating that cattle breed is a factor that influences the establishment of rumen virome. These results suggest the possibility of rumen virus transmission from mother to offspring and its potential to influence beef production traits. These rumen viral genomes and findings provide new insights into the characterizations of the rumen viruses.

Silage preparation and sustainable livestock production of natural woody plant.

As the global population increases and the economy grows rapidly, the demand for livestock products such as meat, egg and milk continue to increase. The shortage of feed in livestock production is a worldwide problem restricting the development of the animal industry. Natural woody plants are widely distributed and have a huge biomass yield. The fresh leaves and branches of some woody plants are rich in nutrients such as proteins, amino acids, vitamins and minerals and can be used to produce storage feed such as silage for livestock. Therefore, the development and utilization of natural woody plants for clean fermented feed is important for the sustainable production of livestock product. This paper presents a comprehensive review of the research progress, current status and development prospects of forageable natural woody plant feed resources. The nutritional composition and uses of natural woody plants, the main factors affecting the fermentation of woody plant silage and the interaction mechanism between microbial co-occurrence network and secondary metabolite are reviewed. Various preparation technologies for clean fermentation of woody plant silage were summarized comprehensively, which provided a sustainable production mode for improving the production efficiency of livestock and producing high-quality livestock product. Therefore, woody plants play an increasingly important role as a potential natural feed resource in alleviating feed shortage and promoting sustainable development of livestock product.

Truck collisions attributed to falling asleep at the wheel in two commercial drivers prescribed oral appliance therapy for obstructive sleep apnea.

Falling asleep at the wheel is attributed to sleepiness, and obstructive sleep apnea is a significant cause of sleepiness that increases the risk of motor vehicle collisions due to falling asleep at the wheel. Although continuous positive airway pressure therapy for obstructive sleep apnea reduces the risk of motor vehicle collisions, similar evidence for alternatives such as oral appliance therapy is lacking. We discuss two truck collisions attributed to microsleep confirmed with dashcam video footage of commercial drivers with obstructive sleep apnea. Our results highlight the current situation where there is insufficient evidence for the prevention and reduction of the risk of motor vehicle collisions by oral appliance therapy, objective adherence monitoring of oral appliance therapy, and effectiveness confirmation tests. Therefore, it is suggested that for commercial truck drivers who require a high level of driving safety, careful selection for oral appliance therapy, systematic follow-up, and monitoring of the driver and truck status with dashcam video footage are crucial. CITATION: Kumagai H, Tsuda H, Kawaguchi K, et al. Truck collisions attributed to falling asleep at the wheel in two commercial drivers prescribed oral appliance therapy for obstructive sleep apnea. J Clin Sleep Med. 2023;19(12):2117-2122.

Dashcam video footage-based analysis of microsleep-related behaviors in truck collisions attributed to falling asleep at the wheel.

OBJECTIVE: With the rapid spread of dashcams, many car accidents have been recorded; however, behavioral approaches using these dashcam video footage have not been sufficiently examined. We employed dashcam video footage to evaluate microsleep-related behaviors immediately prior to real-world truck collisions in professional drivers to explore a new solution to reduce collisions attributed to falling asleep at the wheel. METHODS: In total, 3,120 s of video footage (60 s/case × 52 cases) from real-world truck collisions of 52 professional drivers obtained from interior and exterior dashcams were used and visually analyzed in a second-by-second manner to simultaneously evaluate any eye changes and microsleep-related behaviors (the driver's anti-sleepiness behavior, behavioral signs of microsleep, and abnormal vehicle behavior) during driving. RESULTS: Assessment of the frequency of occurrence of each item of microsleep-related behavior in the 52 collisions revealed that the item "touching" in terms of anti-sleepiness behavior, "absence of body movement" in terms of behavioral signs of microsleep, and "inappropriate line crossing" in terms of abnormal vehicle behavior were observed at the highest rate in all drivers (46.2%, 75.0%, and 78.8%, respectively). Decreases in anti-sleepiness behavior coincided with increases in behavioral signs of microsleep and abnormal vehicle behavior, with collisions occurring within approximately 40 s of these changes. Collisions were more common among young people and in the early morning and evening. CONCLUSION: Our dashcam video footage-based analysis in truck collisions attributed to falling asleep at the wheel revealed the process of changes in microsleep-related driver and vehicle behaviors, classified as anti-sleepiness behavior, behavioral signs of microsleep, and abnormal vehicle behavior. Based on these findings, to prevent collisions caused by falling asleep at the wheel, it is crucial to monitor not only the driver's eyes, but also the driver's whole body and vehicle behavior simultaneously to reliably detect microsleep-related behaviors.

Advanced emergency braking system reduces the risk of motor vehicle collisions caused by falling asleep while driving in patients with untreated obstructive sleep apnea.

Obstructive sleep apnea leads to excessive daytime sleepiness and cognitive dysfunction, which are risk factors for motor vehicle collisions. We aimed to clarify if vehicles with an advanced emergency braking system could reduce motor vehicle collisions caused by falling asleep while driving among patients with untreated obstructive sleep apnea. We enrolled patients with untreated obstructive sleep apnea who underwent polysomnography. The questionnaires included the Epworth Sleepiness Scale, Pittsburgh Sleep Quality Index, history of drowsy driving accidents, and use of an advanced emergency braking system. Multivariate analysis was performed, and odds ratios and 95% confidence intervals were calculated. This study included 1097 patients (mean age, 51.2 ± 12.9 years). Collisions caused by falling asleep while driving were recorded in 59 (5.4%) patients, and were more frequently observed in vehicles without an advanced emergency braking system (p = 0.045). Multivariate analysis showed that these collisions were associated with use of an advanced emergency braking system (odds ratio [95% confidence interval]: 0.39 [0.16-0.97], p = 0.04), length of driving (2.79 [1.19-6.50], p = 0.02), total sleep time (2.40 [1.62-3.55], p < 0.0001), sleep efficiency (0.94 [0.90-0.98], p = 0.003) and periodic limb movement index (1.02 [1.01-1.03], p = 0.004). The collision risk caused by falling asleep while driving in vehicles with an advanced emergency braking system was significantly lower. This study indicates that advanced emergency braking systems may be a preventive measure to reduce motor vehicle collisions among patients with untreated obstructive sleep apnea.

Nocturnal hypoxemia is related to morning negative affectivity in untreated patients with severe obstructive sleep apnea.

The relationship between sleep apnea and morning affectivity remains unclear. We aimed to clarify how sleep disturbance in patients with obstructive sleep apnea (OSA) influences their affectivity. The enrolled participants underwent the Positive and Negative Affect Schedule on their beds immediately before and after overnight polysomnography. Thirty patients with OSA were divided into two groups according to the apnea-hypopnea index (AHI): mild to moderate OSA (5 ≤ AHI < 30/h) and severe OSA (AHI ≥ 30/h) groups. Additionally, 11 healthy participants (AHI < 5/h) were included as the control group. No independent association was found between affectivity and OSA severity markers in the whole population; however, the severe OSA group had a significantly higher cumulative percentage of sleep time at saturations < 90% (CT90) and worsened morning negative affectivity. Multiple regression analysis showed that CT90 was an independent factor for increasing negative affectivity in the severe OSA group (p = 0.0422). In patients with OSA, the receiver operating characteristic curve analysis showed that the best cutoff value for CT90 for predicting no decrease in negative affectivity after sleep was 1.0% (sensitivity = 0.56, specificity = 0.86); the corresponding area under the curve was 0.71. Worsening of negative affectivity in the morning was influenced by nocturnal hypoxemia in patients with severe OSA.

Identification of 146 Metagenome-assembled Genomes from the Rumen Microbiome of Cattle in Japan.

The rumen contains a complex microbial ecosystem that degrades plant materials, such as cellulose and hemicellulose. We herein reconstructed 146 nonredundant, rumen-specific metagenome-assembled genomes (MAGs), with ≥50% completeness and <10% contamination, from cattle in Japan. The majority of MAGs were potentially novel strains, encoding various enzymes related to plant biomass degradation and volatile fatty acid production. The MAGs identified in the present study may be valuable resources to enhance the resolution of future taxonomical and functional studies based on metagenomes and metatranscriptomes.

Effects of Continuous Positive Airway Pressure Therapy on Nocturnal Blood Pressure Fluctuation Patterns in Patients with Obstructive Sleep Apnea.

This retrospective study was designed to evaluate the effects of continuous positive airway pressure (CPAP) therapy, a well-established treatment for obstructive sleep apnea (OSA), on nocturnal blood pressure fluctuations (NBPFs) during rapid eye movement (REM) and non-REM sleep, and to evaluate the NBPF patterns in patients with OSA. We included 34 patients with moderate-to-severe OSA who underwent polysomnography using pulse transit time before and at 3−6 months after CPAP therapy. Nocturnal BP and NBPF frequency in REM and non-REM sleep were investigated, as well as NBPF pattern changes after receiving CPAP therapy. CPAP therapy resulted in significant reductions in the apnea−hypopnea index (AHI), arousal index, nocturnal systolic and diastolic BP, and NBPF frequency in REM and non-REM sleep (all p < 0.01). A higher AHI before CPAP resulted in lower nocturnal systolic BP (r = 0.40, p = 0.019) and NBPFs (r = 0.51, p = 0.002) after CPAP. However, 58.8% of patients showed no change in NBPF patterns with CPAP therapy. CPAP therapy significantly improved almost all sleep-related parameters, nocturnal BP, and NBPF frequency in REM and non-REM sleep periods, but NBPF patterns showed various changes post-CPAP therapy. These results suggest that factors other than OSA influence changes in NBPF patterns.

Efficacy of a Combination Therapy for Difficulties Waking Up in Non-School-Attending Students.

School non-attendance due to difficulties waking up is increasing in Japan, and affected students are commonly diagnosed with orthostatic dysregulation (OD); however, OD-associated sleep problems are overlooked. To date, no sleep-medicine-based treatment for wake-up difficulties in non-school-attending students has been established. This study aimed to assess the efficacy of a novel combination therapy for these students. We assessed the combined effect of sleep hygiene guidance, low-dose aripiprazole administration (3 mg/day), and blue-light exposure on wake-up difficulty in 21 non-school-attending teenage patients. The patients were evaluated using sleep studies and questionnaires before and after treatment. The average subjective total sleep time calculated from sleep diaries before treatment in the patients was 10.3 h. The therapy improved wake-up difficulty by 85.7% and further improved school non-attendance by 66.7%. The subjective sleep time significantly decreased by 9.5 h after treatment (p = 0.0004). The self-rating Depression Scale and mental component summary of the 36-item Short-Form Health Survey significantly improved after treatment (p = 0.002 and p = 0.01, respectively). Wake-up difficulties were caused by the addition of a delayed sleep phase to the patients' long sleep times. The novel combination therapy was effective in improving wake-up difficulty and mental quality of life in non-school-attending teenage students.

Effects of calcium salt of linseed oil fatty acid with different oil adsorbents on in vitro gas production and ruminal fermentation characteristics.

We investigated the effects of supplementary calcium salt of fatty acid (CSFA) from linseed oil with different oil adsorbents on in vitro gas production and rumen fermentation characteristics in barley substrate condition. A non-supplementation treatment (CONT) and treatments of six products, CSFA without oil adsorbent (2.1 fatty acid/Ca molar ratio) and CSFAs with silica gel, zeolite, bentonite, diatomite, and vermiculite (2.8 fatty acid/Ca molar ratio), were prepared. The supplementary 2% and 4% CSFA with silica gel (+S) in the substrate reduced CH4 production 56% and 79%, respectively, compared with that in CONT (p < 0.01). The products, except for +S, did not decrease CH4 production. The dry matter (DM) disappearance in CSFAs with oil adsorbents was lower than that in the CSFA without oil adsorbent (74.8%-77.3% vs. 79.3%, p < 0.01), and crude protein (CP) disappearance in +S supplementation was lower than that of the other products (53.5% vs. 57.2%-59.1%, p < 0.01). The +S supplementation decreased acetate proportion and increased propionate proportion (p < 0.01). Our study indicated that although the disappearance of DM and CP might decrease, using silica gel as an oil adsorbent of linseed oil calcium salt with high fatty acid/Ca molar ratio has the potential to mitigate CH4 emissions from ruminants.

Taxonomic and functional characterization of the rumen microbiome of Japanese Black cattle revealed by 16S rRNA gene amplicon and metagenome shotgun sequencing.

This study aimed to determine the taxonomic and functional characteristics of the Japanese Black (JB) steer rumen microbiome. The rumen microbiomes of six JB steers (age 14.7 ± 1.44 months) and six JB sires × Holstein dams crossbred (F1) steers (age 11.1 ± 0.39 months), fed the same diet, were evaluated. Based on 16S rRNA gene sequencing, the beta diversity revealed differences in microbial community structures between the JB and F1 rumen. Shotgun sequencing showed that Fibrobacter succinogenes and two Ruminococcus spp., which are related to cellulose degradation were relatively more abundant in the JB steer rumen than in the F1 rumen. Furthermore, the 16S rRNA gene copy number of F. succinogenes was significantly higher in the JB steer rumen than in the F1 rumen according to quantitative real-time polymerase chain reaction analysis. Genes encoding the enzymes that accelerate cellulose degradation and those associated with hemicellulose degradation were enriched in the JB steer rumen. Although Prevotella spp. were predominant both in the JB and F1 rumen, the genes encoding carbohydrate-active enzymes of Prevotella spp. may differ between JB and F1.

Nocturnal Blood Pressure Fluctuations in Patients with Rapid Eye Movement-Related Obstructive Sleep Apnea.

Rapid eye movement-related obstructive sleep apnea (REM-related OSA) is a polysomnographic phenotype. Nocturnal blood pressure (BP) fluctuations remain unclear in patients with REM-related OSA. We studied 27 patients with REM-related OSA, categorized as having REM-apnea-hypopnea index (REM-AHI) ≥ 5/h, REM-AHI/non-REM-AHI ≥ 2, and non-REM-AHI < 15/h. Beat-to-beat systolic BP (SBP) variability and nocturnal SBP fluctuation patterns using pulse transit time (PTT) were investigated. The maximum increase and average nocturnal SBP were significantly higher in males than in females (p = 0.003 and p = 0.008, respectively). The rate of non-dipping patterns in nocturnal SBP fluctuations was 63% in all patients (males, 70%; females, 50%). Epworth Sleepiness Scale (ESS) and Self-rating Depression Scale (SDS) scores in females were higher than those in males (8.4 ± 6.1 vs. 13.4 ± 5.4 points, p = 0.04; 43.8 ± 7.9 vs. 52 ± 11.6 points, p = 0.04, respectively). A high proportion of patients with REM-related OSA had a non-dipping pattern. Using PPT, we observed that in patients with REM-related OSA, SBP variability was greater in males. Despite clinical symptoms being slightly more severe in females, nocturnal SBP fluctuations should be considered in male patients with REM-related OSA.

Changes in pelvic alignment in a woman before and after childbirth, using three-dimensional pelvic models based on magnetic resonance imaging: A longitudinal observation case report.

3-dimensional pelvic models based on magnetic resonance images (MRI) can be used to investigate accuracy and specifics of changing pelvic alignment during pregnancy and after childbirth. Few studies have investigated changes of pelvic alignment during pregnancy and after childbirth using three-dimensional pelvic models. This case report documents the changes of pelvic alignment during late pregnancy and after childbirth using MRI-based three-dimensional (3D) pelvic models. This was a longitudinal observation case report. A woman was imaged with MRI at 28 and 39 gestational weeks, as well as 4 and 72 weeks after childbirth. Greater internal, anterior, and downward rotation of both innominates at week 39 was observed from that at gestation week 28. Decreased internal, anterior, and downward rotation of both innominates at week 4 after child birth was observed compared with that at gestation week 39. We report the first case in Japan of changes of pelvic alignment measured using an MRI-based 3D pelvic alignment model during pregnancy and after child birth. This case suggests that the small changes of pubic area and greater separation of anterior portions of sacroiliac joints. Internal, anterior, and downward rotation of both innominates was observed in a Japanese primipara woman having no pelvic pain.

In vitro ruminal fermentation characteristics of gum arabic under concentrate and forage substrate conditions.

Gum arabic (GA) has potential rumen modifier functions. This is the first study to investigate the in vitro ruminal fermentation characteristics of GA. Rumen fluid was collected from ruminal fistulated wethers; rolled barley and ryegrass straw were used as substrates for concentrate and forage conditions, respectively. Besides incubating with the substrates alone (control), GA or potato starch (PS) was added at 0.2%, 1.0%, and 2.0% along with substrates. Under the concentrate substrate condition, GA treatments showed higher total gas production in 24-h incubation, but lower methane production in 24- and 48-h incubation compared with PS treatments (p < 0.05). The 1.0% and 2.0% GA and 0.2% and 1.0% PS treatments showed higher dry matter and neutral detergent fiber digestibility and lower NH3 -N, and higher short chain fatty acid concentrations compared with the control at 24-h incubation (p < 0.05). The GA treatments also showed a lower acetate/propionate ratio than PS treatments at 48-h incubation (p < 0.01). Under the forage substrate condition, the treatment effects were not significant, except for a higher proportion of propionate with GA than with PS at 24 and 48 h of incubations. We thus concluded that GA supplement may exert potential rumen modifier effects particularly under concentrate feeding condition.

Effects of Heat Stress on Heart Rate Variability in Free-Moving Sheep and Goats Assessed With Correction for Physical Activity.

Heart rate variability (HRV) is the heart beat-to-beat variation under control of the cardiovascular function of animals. Under stressed conditions, cardiac activity is generally regulated with an upregulated sympathetic tone and withdrawal of vagal tone; thus, HRV monitoring can be a non-invasive technique to assess stress level in animals especially related to animal welfare. Among several stress-induced factors, heat stress is one of the most serious causes of physiological damage to animals. The aim of this study was to assess the effects of heat stress on HRV in small ruminants under free-moving conditions. In three experimental periods (June, August, and October), inter-beat intervals in sheep and goats (three for each) in two consecutive days were measured. HRV parameters were calculated from the inter-beat interval data by three types of analyses: time domain, frequency domain, and non-linear analyses. The temperature-humidity index (THI) was used as an indicator of heat stress, and vectorial dynamic body acceleration (VeDBA) was calculated to quantify the physical activity of the animals tested. First, we investigated correlations of THI and VeDBA with HRV parameters; subsequently, THI was divided into five categories according to the values obtained (≤ 65, 65-70, 70-75, 75-80, and >80), and the effects of the THI categories on HRV parameters were investigated with and without correcting for the effects of physical activity based on the VeDBA. The results indicated that HRV significantly decreased with increasing THI and VeDBA. For non-linear HRV parameters that were corrected for the effects of physical activity, it was suggested that there would be a threshold of THI around 80 that strongly affected HRV; high heat stress can affect the autonomic balance of animals non-linearly by inducing the sympathetic nervous system. In conclusion, to assess psychophysiological conditions of unrestrained animals by HRV analysis, the confounding effect of physical activity on HRV should be minimized for a more precise interpretation of the results.

Periodic changes in chemical composition and in vitro digestibility of locally available Gramineae feed resources in the Philippines.

Efficient utilization of locally available feed resources is needed for further development of livestock productions in the tropics. However, an inadequate supply of nourish grass is common, and limited information exists regarding the chemical composition and digestibility of locally available feed resources in the different season. There were few reliable information concerning nutritive value of Gramineae resources in dry and rainy seasons in the Philippines. Hence, the present study was conducted to identify the chemical composition and in vitro digestibility of nine kinds of locally available Gramineae feed resources in dry and rainy seasons in the Philippines. The concentration of dry matter (DM), crude protein, and crude fiber of grass samples did not differ among species and seasons. The concentration of organic matter (OM), ether extract (EE), crude ash (CA), nitrogen-free extract (NFE), acid detergent fiber, and neutral detergent fiber (NDF) of grass samples differed significantly among species in both seasons except the NDF in the rainy season. However, the OM, CA, and NDF concentrations of the samples showed no differences between seasons. Imperata cylindrica showed the highest concentration of OM among the samples. Brachiaria brizantha had the lowest EE concentration among the grasses. The lowest NFE concentration was identified in Panicum maximum among the grasses. Although the digestibility of DM (DMD), OM (OMD), and NDF (NDFD) of grass samples showed significant differences among species. The DMD, OMD, and NDFD of I. cylindrica were the lowest among the samples, though Pennisetum purpureum showed the highest DMD, OMD, and NDFD among the species. Relatively high nutritive values of P. purpureum were remarkable among the samples in the present survey area.

Calcium salts of long-chain fatty acids from linseed oil decrease methane production by altering the rumen microbiome in vitro.

Calcium salts of long-chain fatty acids (CSFA) from linseed oil have the potential to reduce methane (CH4) production from ruminants; however, there is little information on the effect of supplementary CSFA on rumen microbiome as well as CH4 production. The aim of the present study was to evaluate the effects of supplementary CSFA on ruminal fermentation, digestibility, CH4 production, and rumen microbiome in vitro. We compared five treatments: three CSFA concentrations-0% (CON), 2.25% (FAL) and 4.50% (FAH) on a dry matter (DM) basis-15 mM of fumarate (FUM), and 20 mg/kg DM of monensin (MON). The results showed that the proportions of propionate in FAL, FAH, FUM, and MON were increased, compared with CON (P < 0.05). Although DM and neutral detergent fiber expressed exclusive of residual ash (NDFom) digestibility decreased in FAL and FAH compared to those in CON (P < 0.05), DM digestibility-adjusted CH4 production in FAL and FAH was reduced by 38.2% and 63.0%, respectively, compared with that in CON (P < 0.05). The genera Ruminobacter, Succinivibrio, Succiniclasticum, Streptococcus, Selenomonas.1, and Megasphaera, which are related to propionate production, were increased (P < 0.05), while Methanobrevibacter and protozoa counts, which are associated with CH4 production, were decreased in FAH, compared with CON (P < 0.05). The results suggested that the inclusion of CSFA significantly changed the rumen microbiome, leading to the acceleration of propionate production and the reduction of CH4 production. In conclusion, although further in vivo study is needed to evaluate the reduction effect on rumen CH4 production, CSFA may be a promising candidate for reduction of CH4 emission from ruminants.

Effects of feeding mother liquor, by-product of monosodium glutamate, on digestibility, energy and nitrogen balances, and rumen condition in Thai native bulls.

Four Thai native bulls were used to evaluate the availability of mother liquor (ML), by-product of monosodium glutamate, as a replacement of soybean meal (SBM) consisting of 10% in concentrate. The SBM was replaced by the ML at 0% (C), 20% (T1), 40% (T2), and 60% (T3), and the experiment was a randomized block design experiment. The animals were fed concentrate and roughage (60:40, on a dry matter [DM] basis). There were no significant differences in the digestibility of DM, crude protein, ether extract, acid detergent fiber expressed exclusive of residual ash and non-fibrous carbohydrate, and energy and nitrogen balances among the treatments. However, the digestibility of the neutral detergent fiber in T2 was lower than the other treatments (p < .05). The valeric acid of T2 was lower than those of C and T1 and the iso-valeric acid of T3 was the lowest (p < .05), followed by those of T2, T1, and C at 4 hr post-feeding. No significant differences were observed in the ruminal total VFA concentrations, pH, and NH3 -N among the treatments. These results suggested that SBM could be replaced by the ML up to 60% without adverse effects on nitrogen and energy balance, rumen conditions, and blood metabolites in Thai native bulls.