Rumen Function

A special issue of Animals (ISSN 2076-2615). This special issue belongs to the section "Animal Physiology".

Deadline for manuscript submissions: closed (30 June 2021) | Viewed by 38466

Special Issue Editor


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Guest Editor
Facultad de Veterinaria, Universidad de Zaragoza, Zaragoza, Spain
Interests: animal nutrition; ruminants; intake; intake markers; rumen digestion; rumen microbiology; kinetics of rumen contents; transit and flow markers

Special Issue Information

Dear Colleagues,

Ruminants are unique in that they possess a fermentation chamber that allows the nutritional use of lignocellulosic resources and its transformation into animal products. This involves a plethora of processes including feed particle comminution, microbial fermentation and passage out of the rumen of feed residues, microbes and products of fermentation. All these processes are affected by the rate of passage of the digesta through the rumen which is in turn related to the intake level resulting from the chemical composition and physical characteristics of the diet, as well as from the animal’s energy requirements. Absorption of fermentation products through the rumen wall is also a mechanism of paramount importance that is affected by the rumen environment resulting from the fermentative process. As a result, rumen function is a highly complex biological process which is the result of multiple interactions between numerous factors. Although a lot of work on these topics has been published during the last half century, recent methodological approaches have allowed deeper investigation in, for example, rumen microbial dynamics or absorption through the rumen wall. Also particle kinetics might deserve a revisit to enhance our knowledge of rumen function.

Prof. Antonio De Vega
Guest Editor

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Keywords

  • particle kinetics
  • rumen kinetics
  • rumen absorption
  • rumen microbes
  • rate of passage

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Published Papers (10 papers)

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Research

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14 pages, 19269 KiB  
Article
Investigating the Reciprocal Interrelationships among the Ruminal Microbiota, Metabolome, and Mastitis in Early Lactating Holstein Dairy Cows
by Shih-Te Chuang, Kuan-Yi Li, Po-Wen Tu, Shang-Tse Ho, Cheng-Chih Hsu, Jui-Chun Hsieh and Ming-Ju Chen
Animals 2021, 11(11), 3108; https://doi.org/10.3390/ani11113108 - 30 Oct 2021
Cited by 10 | Viewed by 2326
Abstract
Mastitis in dairy cow significantly affects animal performance, ultimately reducing profitability. The reciprocal interrelationships among ruminal microbiota, metabolome, and mastitis combining early inflammatory factors (serum proinflammatory cytokines) in lactating dairy cows has not been explored, thus, this study evaluated these reciprocal interrelationships in [...] Read more.
Mastitis in dairy cow significantly affects animal performance, ultimately reducing profitability. The reciprocal interrelationships among ruminal microbiota, metabolome, and mastitis combining early inflammatory factors (serum proinflammatory cytokines) in lactating dairy cows has not been explored, thus, this study evaluated these reciprocal interrelationships in early lactating Holstein dairy cows to identify potential microbial biomarkers and their relationship with ruminal metabolites. The ruminal fluid was sampled from 8 healthy and 8 mastitis cows for the microbiota and metabolite analyses. The critical ruminal microbial biomarkers and metabolites related to somatic cell counts (SCC) and serum proinflammatory cytokines were identified by the linear discriminant analysis effect size (LEfSe) algorithm and Spearman’s correlation analysis, respectively. The SCC level and proinflammatory cytokines positively correlated with Sharpea and negatively correlated with Ruminococcaceae UCG-014, Ruminococcus flavefaciens, and Treponema saccharophilum. Furthermore, the metabolites xanthurenic acid, and 1-(1H-benzo[d]imidazol-2-yl) ethan-1-ol positively correlated with microbial biomarkers of healthy cows, whereas, xanthine, pantothenic acid, and anacardic acid were negatively correlated with the microbial biomarkers of mastitis cows. In conclusion, Ruminococcus flavefaciens and Treponema saccharophilum are potential strains for improving the health of dairy cows. The current study provides a novel perspective to assist in targeting the ruminal microbiota with preventive/therapeutic strategies against inflammatory diseases in the future. Full article
(This article belongs to the Special Issue Rumen Function)
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13 pages, 2185 KiB  
Article
Rumen Fermentation, Digestive Enzyme Activity, and Bacteria Composition between Pre-Weaning and Post-Weaning Dairy Calves
by Yangyi Hao, Chunyan Guo, Yue Gong, Xiaoge Sun, Wei Wang, Yajing Wang, Hongjian Yang, Zhijun Cao and Shengli Li
Animals 2021, 11(9), 2527; https://doi.org/10.3390/ani11092527 - 28 Aug 2021
Cited by 23 | Viewed by 3944
Abstract
To better understand the transition of rumen function during the weaning period in dairy calves, sixteen Holstein dairy calves were selected and divided into two groups: pre-weaning (age = 56 ± 7 day, n = 8) and post-weaning (age = 80 ± 6 [...] Read more.
To better understand the transition of rumen function during the weaning period in dairy calves, sixteen Holstein dairy calves were selected and divided into two groups: pre-weaning (age = 56 ± 7 day, n = 8) and post-weaning (age = 80 ± 6 day, n = 8). The rumen fluid was obtained by an oral gastric tube. The rumen fermentation profile, enzyme activity, bacteria composition, and their inter-relationship were investigated. The results indicated that the post-weaning calves had a higher rumen acetate, propionate, butyrate, and microbial crude protein (MCP) than the pre-weaning calves (p < 0.05). The rumen pH in the post-weaning calves was lower than the pre-weaning calves (p < 0.05). The protease, carboxymethyl cellulase, cellobiohydrolase, and glucosidase in the post-weaning calves had a lower trend than the pre-weaning calves (0.05 < p < 0.1). There was no difference in α and β diversity between the two groups. Linear discriminant analysis showed that the phylum of Fibrobacteres in the post-weaning group was higher than the pre-weaning group. At the genus level, Shuttleworthia, Rikenellaceae, Fibrobacter, and Syntrophococcus could be worked as the unique bacteria in the post-weaning group. The rumen bacteria network node degree in the post-weaning group was higher than the pre-weaning group (16.54 vs. 9.5). The Shuttleworthia genus was highly positively correlated with MCP, propionate, total volatile fatty acid, glucosidase, acetate, and butyrate (r > 0.65, and p < 0.01). Our study provided new information about the rumen enzyme activity and its relationship with bacteria, which help us to better understand the effects of weaning on the rumen function. Full article
(This article belongs to the Special Issue Rumen Function)
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14 pages, 1413 KiB  
Article
Metabolic Profiling of Rumen Fluid and Milk in Lactating Dairy Cattle Influenced by Subclinical Ketosis Using Proton Nuclear Magnetic Resonance Spectroscopy
by Jun-Sik Eom, Hyun-Sang Kim, Shin-Ja Lee, You-Young Choi, Seong-Uk Jo, Jaemin Kim, Sang-Suk Lee, Eun-Tae Kim and Sung-Sill Lee
Animals 2021, 11(9), 2526; https://doi.org/10.3390/ani11092526 - 27 Aug 2021
Cited by 12 | Viewed by 3345
Abstract
Ketosis metabolic research on lactating dairy cattle has been conducted worldwide; however, there have been very few Korean studies. Biofluids from lactating dairy cattle are necessary to study ketosis metabolic diseases. Six Holstein cows were divided into two groups (healthy (CON) and subclinical [...] Read more.
Ketosis metabolic research on lactating dairy cattle has been conducted worldwide; however, there have been very few Korean studies. Biofluids from lactating dairy cattle are necessary to study ketosis metabolic diseases. Six Holstein cows were divided into two groups (healthy (CON) and subclinical ketosis diagnosed (SCK)). Rumen fluid and milk samples were collected using a stomach tube and a pipeline milking system, respectively. Metabolites were determined using proton nuclear magnetic resonance (NMR) spectroscopy and they were identified and quantified using the Chenomx NMR Suite 8.4 software and Metaboanalyst 5.0. In the rumen fluid of the SCK group, butyrate, sucrose, 3-hydroxybutyrate, maltose, and valerate levels were significantly higher than in the CON group, which showed higher levels of N,N-dimethylformamide, acetate, glucose, and propionate were significantly higher. Milk from the SCK group showed higher levels of maleate, 3-hydroxybutyrate, acetoacetate, galactonate, and 3-hydroxykynurenine than that from the CON group, which showed higher levels of galactitol, 1,3-dihydroxyacetone, γ-glutamylphenylalanine, 5-aminolevulinate, acetate, and methylamine. Some metabolites are associated with ketosis diseases and the quality of rumen fluid and milk. This report will serve as a future reference guide for ketosis metabolomics studies in Korea. Full article
(This article belongs to the Special Issue Rumen Function)
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13 pages, 2947 KiB  
Article
Effects of Heated Drinking Water on the Growth Performance and Rumen Functionality of Fattening Charolaise Beef Cattle in Winter
by Silvia Grossi, Luciana Rossi, Matteo Dell’Anno, Stefano Biffani and Carlo Angelo Sgoifo Rossi
Animals 2021, 11(8), 2218; https://doi.org/10.3390/ani11082218 - 27 Jul 2021
Cited by 13 | Viewed by 3550
Abstract
The effects of heated drinking water on growth performance and rumen functionality in fattening beef cattle during winter were evaluated. Newly received Charolaise bulls (n = 224) were allocated to two experimental groups: (i) water at room temperature (RTW) (weight 408 ± [...] Read more.
The effects of heated drinking water on growth performance and rumen functionality in fattening beef cattle during winter were evaluated. Newly received Charolaise bulls (n = 224) were allocated to two experimental groups: (i) water at room temperature (RTW) (weight 408 ± 34 kg); (ii) constantly heated water (25 °C) (HW) (weight 405 ± 38 kg). Growth performances, feed intake, feed conversion rate, water intake and carcass characteristics were evaluated. Internal reticuloruminal wireless boluses were used to collect rumen pH and temperature values every 10 min. Bodyweight was not affected by the water temperature, but the overall average daily gain (ADG) was significantly higher in the HW group (1.486 vs. 1.438 kg/head/day in the RTW; p = 0.047). Dry matter intake was significantly higher in the HW group (p = 0.001), even though the final feed conversion rate (FCR) was not influenced. There was also a tendency for better cold carcass weight (CCW) and carcass yield (CY) in the HW group. Drinking heated water reduced the time (min/day) during which the ruminal pH was below pH 5.8 or 5.5, and the time during which the temperature was lower than 37 or 39 °C (p < 0.001). The use of heated drinking water is a plausible a strategy for enhancing ruminal stability and the overall production efficiency in fattening beef cattle, which will lead to both better growth performance and higher ruminal stability. Full article
(This article belongs to the Special Issue Rumen Function)
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11 pages, 516 KiB  
Article
Rumen Fermentation Characteristics Require More Time to Stabilize When Diet Shifts
by Qinghua Qiu, Chaoyu Gao, Huawei Su and Binghai Cao
Animals 2021, 11(8), 2192; https://doi.org/10.3390/ani11082192 - 23 Jul 2021
Cited by 5 | Viewed by 3306
Abstract
This study was conducted to explore the proper time required to achieve stabilization in digestibility, serum metabolism, and rumen fermentation characteristics when different diets shift, thus providing decision-making of practical sampling frequency for basal nutritional research. For these purposes, 12 Holstein steers (body [...] Read more.
This study was conducted to explore the proper time required to achieve stabilization in digestibility, serum metabolism, and rumen fermentation characteristics when different diets shift, thus providing decision-making of practical sampling frequency for basal nutritional research. For these purposes, 12 Holstein steers (body weight 467 ± 34 kg, age 14 ± 0.5 months) were equally assigned to two dietary treatments: high-density (metabolizable energy (ME) = 2.53 Mcal/kg and crude protein (CP) = 119 g/kg; both ME and CP were expressed on a dry matter basis) or low-density (ME = 2.35 Mcal/kg and CP = 105 g/kg). The samples of feces, serum, and rumen contents were collected with a 30-day interval. All data involved in this study were analyzed using the repeated measures in mixed model of SPSS. Results showed that nutrient apparent digestibility and serum metabolic parameters were stable across each monthly collection, while most rumen fermentation characteristics, namely concentrations of acetate, propionate, isobutyrate, and valerate, were affected by the interaction effects between collection period and dietary density. These findings indicate that rumen fermentation characteristics require more time to stabilize when diet shifts. It is recommended to collect ruminal digesta monthly to evaluate rumen fermentation characteristics, while unnecessary to sample monthly for digestion trials and blood tests in the long-term fattening of Holstein steers. This study may provide insights into exploring the associations between detected parameters and stabilization time, and between diet type and stabilization time when diet shifts. Full article
(This article belongs to the Special Issue Rumen Function)
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9 pages, 252 KiB  
Article
Dietary Supplementation with Saccharomyces cerevisiae, Clostridium butyricum and Their Combination Ameliorate Rumen Fermentation and Growth Performance of Heat-Stressed Goats
by Liyuan Cai, Jiangkun Yu, Rudy Hartanto and Desheng Qi
Animals 2021, 11(7), 2116; https://doi.org/10.3390/ani11072116 - 16 Jul 2021
Cited by 31 | Viewed by 4607
Abstract
This study aimed to evaluate the effects of Saccharomyces cerevisiae, and their combination on rumen fermentation and growth performance of heat-stressed goats. Twelve heat-stressed goats (20.21 ± 2.30 kg) were divided equally into four groups: control group (CG, fed the basal diet, [...] Read more.
This study aimed to evaluate the effects of Saccharomyces cerevisiae, and their combination on rumen fermentation and growth performance of heat-stressed goats. Twelve heat-stressed goats (20.21 ± 2.30 kg) were divided equally into four groups: control group (CG, fed the basal diet, Saccharomyces cerevisiae supplemented group (SC, 0.60% Saccharomyces cerevisiae added to the basal diet), Clostridium butyricum supplemented group (CB, 0.05% Clostridium butyricum added to the basal diet), and their combination supplemented group (COM 0.60% Saccharomyces cerevisiae and 0.05% Clostridium butyricum added to the basal diet) and were assigned to a 4 × 3 incomplete Latin square design. The rumen fluid and feces were collected for fermentation parameters and feed digestibility analysis, and animal growth performance was also assessed during all the experiment periods. The results showed that rumen pH, rumen cellulolytic enzymes (avicelase, CMCaes, cellobiase, and xylanase) activities, and the concentrations of rumen total volatile fatty acid (TVFA), acetic acid, and propionic acid were significantly increased with Saccharomyces cerevisiae, Clostridium butyricum, and their combination supplementation (p < 0.05). Besides, the dry matter intake (DMI), average daily gain (ADG), and the digestibility of dry matter (DM), neutral detergent fiber (NDF), and acidic detergent fiber (ADF) were significantly increased (p < 0.05) with supplemented these probiotics. However, the ammonia nitrogen (NH3-N) concentration only significantly increased in CB and A/P ratio (acetic acid to propionic acid ratio) only significantly increased in SC and CB. These results indicated that the supplementation with these probiotics could ameliorate rumen fermentation and growth performance of heat-stressed goats. Full article
(This article belongs to the Special Issue Rumen Function)
18 pages, 4312 KiB  
Article
Alterations in Rumen Bacterial Community and Metabolome Characteristics of Cashmere Goats in Response to Dietary Nutrient Density
by Yaoyue Wang, Peng Tang, Yafei Xiao, Jianming Liu, Yulin Chen and Yuxin Yang
Animals 2020, 10(7), 1193; https://doi.org/10.3390/ani10071193 - 14 Jul 2020
Cited by 9 | Viewed by 2714
Abstract
This study was conducted to investigate the impacts of dietary energy and protein on rumen bacterial composition and ruminal metabolites. A total of 12 ruminal samples were collected from Shaanbei white cashmere goats which were divided into two groups, including high-energy and high-protein [...] Read more.
This study was conducted to investigate the impacts of dietary energy and protein on rumen bacterial composition and ruminal metabolites. A total of 12 ruminal samples were collected from Shaanbei white cashmere goats which were divided into two groups, including high-energy and high-protein (Group H; crude protein, CP: 9.37% in dry matter; metabolic energy, ME: 9.24 MJ/kg) and control (Group C; CP: 8.73%; ME: 8.60 MJ/kg) groups. Thereby, 16S rRNA gene sequencing and a quantitative polymerase chain reaction were performed to identify the rumen bacterial community. Metabolomics analysis was done to investigate the rumen metabolites and the related metabolic pathways in Groups C and H. The high-energy and high-protein diets increased the relative abundance of phylum Bacteroidetes and genera Prevotella_1 and Succiniclasticum, while decreasing the number of Proteobacteria (p < 0.05). The dominant differential metabolites were amino acids, peptides, and analogs. Tyrosine metabolism played an important role among the nine main metabolic pathways. Correlation analysis revealed that both Prevotella_1 (r = 0.608, p < 0.05) and Ruminococcus_2 (r = 0.613, p < 0.05) showed a positive correlation with catechol. Our findings revealed that the diets with high energy and protein levels in Group H significantly altered the composition of ruminal bacteria and metabolites, which can help to improve the dietary energy and protein use efficiency in goats. Full article
(This article belongs to the Special Issue Rumen Function)
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19 pages, 2318 KiB  
Article
Differential Dynamics of the Ruminal Microbiome of Jersey Cows in a Heat Stress Environment
by Dong-Hyeon Kim, Myung-Hoo Kim, Sang-Bum Kim, Jun-Kyu Son, Ji-Hwan Lee, Sang-Seok Joo, Bon-Hee Gu, Tansol Park, Beom-Young Park and Eun-Tae Kim
Animals 2020, 10(7), 1127; https://doi.org/10.3390/ani10071127 - 2 Jul 2020
Cited by 22 | Viewed by 4789
Abstract
The microbial community within the rumen can be changed and shaped by heat stress. Accumulating data have suggested that different breeds of dairy cows have differential heat stress resistance; however, the underlying mechanism by which nonanimal factors contribute to heat stress are yet [...] Read more.
The microbial community within the rumen can be changed and shaped by heat stress. Accumulating data have suggested that different breeds of dairy cows have differential heat stress resistance; however, the underlying mechanism by which nonanimal factors contribute to heat stress are yet to be understood. This study is designed to determine changes in the rumen microbiome of Holstein and Jersey cows to normal and heat stress conditions. Under heat stress conditions, Holstein cows had a significantly higher respiration rate than Jersey cows. Heat stress increased the rectal temperature of Holstein but not Jersey cows. In the Kyoto encyclopedia of genes and genomes (KEGG) pathway analysis, Jersey cows had a significantly higher proportion of genes associated with energy metabolism in the normal condition than that with other treatments. Linear discriminant analysis effect size (LEfSe) results identified six taxa as distinguishing taxa between normal and heat stress conditions in Holstein cows; in Jersey cows, 29 such taxa were identified. Changes in the rumen bacterial taxa were more sensitive to heat stress in Jersey cows than in Holstein cows, suggesting that the rumen mechanism is different in both breeds in adapting to heat stress. Collectively, distinct changes in rumen bacterial taxa and functional gene abundance in Jersey cows may be associated with better adaptation ability to heat stress. Full article
(This article belongs to the Special Issue Rumen Function)
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13 pages, 1201 KiB  
Article
Ruminal Methanogenic Responses to the Thiamine Supplementation in High-Concentrate Diets
by Fuguang Xue, Yue Wang, Yiguang Zhao, Xuemei Nan, Dengke Hua, Fuyu Sun, Liang Yang, Linshu Jiang and Benhai Xiong
Animals 2020, 10(6), 935; https://doi.org/10.3390/ani10060935 - 28 May 2020
Cited by 2 | Viewed by 2222
Abstract
Background: Thiamine supplementation in high-concentrate diets (HC) was confirmed to attenuate ruminal subacute acidosis through promoting carbohydrate metabolism, however, whether thiamine supplementation in HC impacts methane metabolism is still unclear. Therefore, in the present study, thiamine was supplemented in the high-concentrate diets to [...] Read more.
Background: Thiamine supplementation in high-concentrate diets (HC) was confirmed to attenuate ruminal subacute acidosis through promoting carbohydrate metabolism, however, whether thiamine supplementation in HC impacts methane metabolism is still unclear. Therefore, in the present study, thiamine was supplemented in the high-concentrate diets to investigate its effects on ruminal methanogens and methanogenesis process. Methods: an in vitro fermentation experiment which included three treatments: control diet (CON, concentrate/forage = 4:6; DM basis), high-concentrate diet (HC, concentrate/forage = 6:4; DM basis) and high-concentrate diet supplemented with thiamine (HCT, concentrate/forage = 6:4, DM basis; thiamine supplementation content = 180 mg/kg DM) was conducted. Each treatment concluded with four repeats, with three bottles in each repeat. The in vitro fermentation was sustained for 48h each time and repeated three times. At the end of fermentation, fermentable parameters, ruminal bacteria and methanogens community were measured. Results: HC significantly decreased ruminal pH, thiamine and acetate content, while significantly increasing propionate content compared with CON (p < 0.05). Conversely, thiamine supplementation significantly increased ruminal pH, acetate while significantly decreasing propionate content compared with HC treatment (p < 0.05). No significant difference of ruminal methanogens abundances among three treatments was observed. Thiamine supplementation significantly decreased methane production compared with CON, while no significant change was found in HCT compared with HC. Conclusion: thiamine supplementation in the high-concentrate diet (HC) could efficiently reduce CH4 emissions compared with high-forage diets while without causing ruminal metabolic disorders compared with HC treatment. This study demonstrated that supplementation of proper thiamine in concentrate diets could be an effective nutritional strategy to decrease CH4 production in dairy cows. Full article
(This article belongs to the Special Issue Rumen Function)
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Review

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11 pages, 758 KiB  
Review
Effects of Ionophores on Ruminal Function of Beef Cattle
by Rodrigo da Silva Marques and Reinaldo Fernandes Cooke
Animals 2021, 11(10), 2871; https://doi.org/10.3390/ani11102871 - 30 Sep 2021
Cited by 30 | Viewed by 5334
Abstract
Ionophores have been widely used in the beef and dairy industry for decades to improve feed efficiency and performance by altering ruminal fermentation dynamics, increasing the level of propionate. Ionophores can also reduce ruminal proteolysis and ammonia synthesis, thus increasing the influx of [...] Read more.
Ionophores have been widely used in the beef and dairy industry for decades to improve feed efficiency and performance by altering ruminal fermentation dynamics, increasing the level of propionate. Ionophores can also reduce ruminal proteolysis and ammonia synthesis, thus increasing the influx of protein into the small intestine in cattle, leading to improvements in performance and efficiency responses. Ionophores indirectly impact ruminal methanogenesis by decreasing the substrate used to produce methane. Despite the consistent benefits of using ionophores in cattle nutrition, their utilization is under public scrutiny due to concerns related to microbial adaptation. However, there is inconsistent evidence supporting these concerns, whereas ionophores are still an important dietary tool to enhance productivity and profitability in beef production systems. Full article
(This article belongs to the Special Issue Rumen Function)
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