Topic Editors

Faculty of Veterinary Medicine and Zootechnics, Autonomous University of Sinaloa, Culiacan 80260, Mexico
Laboratory of Climate Change and Livestock Production, Faculty of Veterinary Medicine and Animal Science, University of Yucatan, C.P., Merida 97100, Mexico
Prof. Dr. Richard Avery Zinn
Department of Animal Science, University of California, Davis, CA 95616, USA

Rumen Fermentation, Microbial Population and Digestibility in Ruminants

Abstract submission deadline
closed (28 February 2023)
Manuscript submission deadline
closed (30 April 2023)
Viewed by
47282

Topic Information

Dear Colleagues,

Feed efficiency is a complex function of nutrient intake in relation to animal growth-performance potential. The windows of opportunity to increase feed efficiency are improves on fermentation and digestion, nutrient absorption, and/or on cellular metabolism. With regard to fermentation and digestion, roughly 80% of the total tract digestible organic matter intake is fermented in the rumen. Hence, understanding the principles of fermentative processes and the limits of the rumen function are key to optimizing nutrient utilization. Knowledge about the complex interactions between microorganisms and the ruminal environment are important research areas to better understand fermentation efficiency, nutrient digestibility, and health. The manipulation of the nutrient availability for microbial fermentation via feed processing and feeding management systems, and modulations in the characteristics of fermentation and ruminal pH by optimizing levels of effective fiber, and tailored use of feed additives are tools that have proven to be useful for this purpose. In addition to aspects directly associated with fermentative efficiency and health, per se, considerable research attention has been directed toward mitigation of methane emissions. In this Topic, we welcome research articles, as well as review articles focusing on: 1) diverse approaches toward mitigation of ruminal methane generation, 2) diet formulation, feeding management, and environmental factors affecting digestive dysfunctions and subacute acidosis 3) diet formulation and feeding management practices affecting ruminal pH and efficiency of ruminal microbial protein synthesis.

Dr. Alejandro Plascencia
Dr. Juan Ku Vera
Prof. Dr. Richard Avery Zinn
Topic Editors

Keywords

  • ruminal fermentation
  • digestive function
  • ruminal metabolism
  • ruminal microbiology
  • manipulation rumen fermentation
  • modeling digesta passage and fermentation
  • methane
  • acidosis
  • feed additives

Participating Journals

Journal Name Impact Factor CiteScore Launched Year First Decision (median) APC
Animals
animals
3.0 4.2 2011 18.1 Days CHF 2400
Ruminants
ruminants
- - 2021 20.9 Days CHF 1000
Sustainability
sustainability
3.9 5.8 2009 18.8 Days CHF 2400
Veterinary Sciences
vetsci
2.4 2.3 2014 19.6 Days CHF 2600

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Published Papers (25 papers)

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11 pages, 1063 KiB  
Article
In Vitro Digestibility and Models of Cumulative Gas Production of Forage-Free Diet
by Luís Carlos Vinhas Ítavo, Antonio Leandro Chaves Gurgel, Camila Celeste Brandão Ferreira Ítavo, Camila Soares Cunha, Vanessa Zirondi Longhini, Gelson dos Santos Difante, Alexandre Menezes Dias, Juliana Caroline Santos Santana, Angelo Herbet Moreira Arcanjo, Marcus Vinicius Garcia Niwa, Lucimara Modesto Nonato, Geraldo Tadeu dos Santos and Alfonso Juventino Chay-Canul
Animals 2023, 13(22), 3515; https://doi.org/10.3390/ani13223515 - 14 Nov 2023
Viewed by 704
Abstract
Our objectives were to evaluate the use of cottonseed cake in replacing corn silage in a diet without forage and to identify the model with higher precision and accuracy of adjustment of parameters of ruminal degradation kinetics. A diet containing corn silage and [...] Read more.
Our objectives were to evaluate the use of cottonseed cake in replacing corn silage in a diet without forage and to identify the model with higher precision and accuracy of adjustment of parameters of ruminal degradation kinetics. A diet containing corn silage and another with cottonseed cake as a fiber source were formulated. Gompertz, Dual-pool Logistic, Brody, and Ørskov models were evaluated for goodness of fit to gas production. There were significant differences in dry matter (DM), organic matter (OM), and neutral detergent fiber (NDF) in the in vitro digestibility for diets and fiber sources. The estimated values of the Gompertz (6.77), Brody (6.72), and Ørskov (6.73) models were similar to the observed mean of gas production in the corn silage diet (6.73 mL/100 mg DM). Similarly, the estimated values of the Brody (5.87) and Ørskov (5.89) models were similar to the observed mean of gas production in the cottonseed cake diet (5.87 mL/100 mg DM). The roughage-free diet containing cottonseed cake as a fiber source stimulated higher gas production. Brody and Ørskov models presented higher precision and accuracy in the fitting of kinetics of degradation independent of the fiber source in the diet. Full article
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17 pages, 2342 KiB  
Article
Effects of a High-Concentrate Diet on the Blood Parameters and Liver Transcriptome of Goats
by Yusu Wang, Qiong Li, Lizhi Wang, Yuehui Liu and Tianhai Yan
Animals 2023, 13(9), 1559; https://doi.org/10.3390/ani13091559 - 06 May 2023
Viewed by 1481
Abstract
The objective of this study was to determine the effect of high-concentrate diets on the blood parameters and liver transcriptome of goats. Eighteen goats were allocated into three dietary treatments: the high level of concentrate (HC) group, the medium level of concentrate (MC) [...] Read more.
The objective of this study was to determine the effect of high-concentrate diets on the blood parameters and liver transcriptome of goats. Eighteen goats were allocated into three dietary treatments: the high level of concentrate (HC) group, the medium level of concentrate (MC) group, and the low level of concentrate (LC) group. The blood parameters and pathological damage of the gastrointestinal tract and liver tissues were measured. In hepatic portal vein blood, HC showed higher LPS, VFAs, and LA; in jugular vein blood, no significant differences in LPS, VFAs, and LA were recorded among groups (p > 0.05). Compared to the LC and MC groups, the HC group showed significantly increased interleukin (IL)-1β, IL-10, TNF-α, and diamine oxidase in jugular vein blood (p < 0.05). Liver transcriptome analysis discovered a total of 1269 differentially expressed genes (DEGs) among the three groups and most of them came from the HC vs. LC group. There were 333 DEGs up-regulated and 608 down-regulated in the HC group compared to the LC group. The gene ontology enrichment analysis showed that these DEGs were mainly focused on the regulation of triacylglycerol catabolism, lipoprotein particle remodeling, and cholesterol transport. The Kyoto Encyclopedia of Genes and Genomes pathway analysis revealed that the liver of the HC group enhanced the metabolism of nutrients such as VFAs through the activation of AMPK and other signaling pathways and enhanced the clearance and detoxification of LPS by activating the toll-like receptor signaling pathway. A high-concentrate diet (HCD) can significantly promote the digestion of nutrients; the liver enhances the adaptability of goats to an HCD by regulating the expression of genes involved in nutrient metabolism and toxin clearance. Full article
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14 pages, 1509 KiB  
Article
Development of a Mobile Open-Circuit Respiration Head Hood System for Measuring Gas Exchange in Camelids in the Andean Plateau
by Wilfredo Manuel Rios Rado, Paola Katherine Chipa Guillen, Dione Huamán Borda, Víctor Vélez Marroquín, José Ignacio Gere, Walter Orestes Antezana Julián and Carlos Fernández
Animals 2023, 13(6), 1011; https://doi.org/10.3390/ani13061011 - 10 Mar 2023
Cited by 1 | Viewed by 1513
Abstract
Peru has the largest inventory of alpacas worldwide. Despite their importance as a source of net income for rural communities living at the Andean Plateau, data on energy requirements and methane (CH4) emissions for alpacas are particularly lacking. In 2019, the [...] Read more.
Peru has the largest inventory of alpacas worldwide. Despite their importance as a source of net income for rural communities living at the Andean Plateau, data on energy requirements and methane (CH4) emissions for alpacas are particularly lacking. In 2019, the International Panel on Climate Change (IPCC; 2006, and Refinement 2019) outlined methods for estimating CH4 emissions from enteric fermentation and no methane (CH4) conversion factors were reported for camelids. IPCC has since updated its guidelines for estimating CH4 emissions from the enteric fermentation of livestock at a national scale. For greenhouse gas (GHG) inventory purposes, conversion factors were developed for ruminants but not for domestic South American camelids (SAC), with this category including alpacas. A mobile open-circuit respirometry system (head hood) for the rapid determination of CH4 and CO2 production, O2 consumption, and thereafter, heat production (HP) for camelids was built and validated. In addition, an experimental test with eight alpacas was conducted for validation purposes. The average HP measured by indirect calorimetry (respiratory quotient (RQ) method) was close to the average HP determined from the carbon–nitrogen balance (CN method); 402 kJ/kg BW0.75 and 398 kJ/kg BW0.75, respectively. Fasting HP was determined by the RQ method and 250 kJ/kg BW0.75 was obtained. The metabolizable energy requirement for maintenance (MEm) was calculated to be 323 kJ/kg BW0.75 with an efficiency of energy utilization of 77%. When intake was adjusted to zero energy retention by linear regression, the MEm requirement increased to 369 kJ/kg BW0.75 and the efficiency decreased up to 68%. The CH4 conversion factor (Ym) was 5.5% on average. Further research is required to gain a better understanding of the energy requirements and CH4 emissions of alpacas in conditions of the Andean Plateau and to quantify them with greater accuracy. Full article
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12 pages, 2019 KiB  
Article
Influence of Parturition on Rumen Bacteria and SCFAs in Holstein Cows Based on 16S rRNA Sequencing and Targeted Metabolomics
by Yansheng Guo, Feifei Wang, Yongxia Mao, Weiyi Kong, Jiandong Wang and Guijie Zhang
Animals 2023, 13(5), 782; https://doi.org/10.3390/ani13050782 - 21 Feb 2023
Cited by 3 | Viewed by 1283
Abstract
The rumen fluids from ten cows at Day 3~5 before calving and Day 0 after calving were collected to analyze the composition and quantity of bacterial communities and concentrations of SCFAs. The results showed that the relative abundances of unidentified Lachnospiraceae, Acetitomaculum, Methanobrevibacter, [...] Read more.
The rumen fluids from ten cows at Day 3~5 before calving and Day 0 after calving were collected to analyze the composition and quantity of bacterial communities and concentrations of SCFAs. The results showed that the relative abundances of unidentified Lachnospiraceae, Acetitomaculum, Methanobrevibacter, Olsenella, Syntrophococcus, Lachnospira, and Lactobacillus genera were significant increased (p < 0.05), while that of unidentified-Prevotellaceae was notably decreased after calving (p < 0.05). In addition, the concentrations of acetic acid, propionic acid, butyric acid, and caproic acid obviously decreased after calving (p < 0.01). Our findings show that parturition altered the rumen microbiota and their fermentation ability in dairy cows. This study defines a rumen bacteria and metabolic profile of SCFAs associated with parturition in dairy cows. Full article
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11 pages, 244 KiB  
Review
Feeding Management Strategies to Mitigate Methane and Improve Production Efficiency in Feedlot Cattle
by Michael L. Galyean and Kristin E. Hales
Animals 2023, 13(4), 758; https://doi.org/10.3390/ani13040758 - 20 Feb 2023
Cited by 10 | Viewed by 2506
Abstract
Mitigation of greenhouse gases and decreasing nutrient excretion have become increasingly important goals for the beef cattle industry. Because feed intake is a major driver of enteric CH4 production and nutrient excretion, feeding management systems could be important mitigation tools. Programmed feeding [...] Read more.
Mitigation of greenhouse gases and decreasing nutrient excretion have become increasingly important goals for the beef cattle industry. Because feed intake is a major driver of enteric CH4 production and nutrient excretion, feeding management systems could be important mitigation tools. Programmed feeding uses net energy equations to determine the feed required to yield a specific rate of gain, whereas restricted feeding typically involves decreasing intake relative to the expected or observed ad libitum intake. In the context of growing/finishing systems typical of those in the United States and Western Canada, experimental results with programmed and restricted feeding have often shown decreased overall feed intake and increased gain efficiency relative to ad libitum feeding, but too much restriction can negatively affect harvest weight and associated carcass quality. Slick feed bunk management is a time-based restriction that limits day-to-day variation in feed deliveries, but the effects on intake and performance are not well defined. Simulations to estimate enteric CH4 emission and nitrogen excretion indicated that programmed feeding of a high-grain diet could appreciably decrease CH4 emissions and nitrogen excretion compared with traditional growing programs based on high-forage diets. For feedlot finishing, programming gain for a portion of the feeding period will decrease CH4 emission and N excretion only if cattle perform better than expected during the programmed phase or if compensatory growth occurs when cattle are transitioned to ad libitum feeding. Optimal approaches to implement programmed or restricted feeding that will yield increased efficiency should be the subject of future research in this area. Full article
13 pages, 524 KiB  
Article
Impact of Molasses on Ruminal Volatile Fatty Acid Production and Microbiota Composition In Vitro
by A. Palmonari, A. Federiconi, D. Cavallini, C. J. Sniffen, L. Mammi, S. Turroni, F. D’Amico, P. Holder and A. Formigoni
Animals 2023, 13(4), 728; https://doi.org/10.3390/ani13040728 - 17 Feb 2023
Cited by 3 | Viewed by 1574
Abstract
The aim of this study was to assess if molasses could modify VFA production and the rumen microbial community in vitro. Three beet (treatment Beet) and three cane (treatment Cane) molasses preparations were randomly selected from a variety of samples collected worldwide and [...] Read more.
The aim of this study was to assess if molasses could modify VFA production and the rumen microbial community in vitro. Three beet (treatment Beet) and three cane (treatment Cane) molasses preparations were randomly selected from a variety of samples collected worldwide and incubated in vitro with rumen fluid along with a control sample (treatment CTR, in which no molasses was used). Flasks for VFA analysis were sampled at 0, 1, 2, 3, 4, 6, 8, and 24 h of each incubation. For microbiota analysis, samples from each fermentation flask after 12 and 24 h were subjected to microbial DNA extraction and V3–V4 16S rRNA gene sequencing on an Illumina MiSeq platform. Total net VFA production was higher in the beet and cane preparations than in the control (CTR) group at 24 h (33 mmol/L, 34 mmol/L, and 24.8 mmol/L, respectively), and the composition of VFAs was affected by the inclusion of molasses: acetic acid increased in the CTR group (73.5 mol%), while propionic acid increased in the beet and cane molasses (19.6 mol% and 18.6 mol%, respectively), and butyric acid increased, especially in the cane group (23.2 mol%). Molasses even influenced the composition of the rumen microbiota, and particularly the relative abundance of the most dominant family in the rumen, Prevotellaceae, which decreased compared to CTR (37.13%, 28.88%, and 49.6%, respectively). In contrast, Streptococcaceae (19.62% and 28.10% in molasses compared to 6.23% in CTR), Veillonellaceae (6.48% and 8.67% in molasses compared to 4.54% in CTR), and Fibrobacteraceae (0.90% and 0.88% in molasses compared to 0.62% in CTR) increased in the beet and cane groups compared to the CTR group. Another important finding is the lower proportion of Methanobacteriaceae following the addition of molasses compared to CTR (0.26%, 0.28%, and 0.43%, respectively). This study showed the impact of molasses in influencing VFA production and composition as a result of a modified rumen microbial composition. Full article
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12 pages, 1483 KiB  
Article
The Effect of Combining Millet and Corn Straw as Source Forage for Beef Cattle Diets on Ruminal Degradability and Fungal Community
by Yaoyi Tong, Jincai Wu, Wenwei Guo, Zhimin Yang, Haocheng Wang, Hongkai Liu, Yong Gao, Maohong Sun and Chunwang Yue
Animals 2023, 13(4), 548; https://doi.org/10.3390/ani13040548 - 04 Feb 2023
Cited by 2 | Viewed by 1131
Abstract
Three ruminal cannulated Simmental crossbreed bulls (approximately 3 years of age and with 380 ± 20 kg live weight at initiation of the experiment) were used in a 3 × 3 Latin square experiment in order to determine the effects of the treatments [...] Read more.
Three ruminal cannulated Simmental crossbreed bulls (approximately 3 years of age and with 380 ± 20 kg live weight at initiation of the experiment) were used in a 3 × 3 Latin square experiment in order to determine the effects of the treatments on ruminal pH and degradability of nutrients, as well as the rumen fungal community. The experimental periods were 21 d, with 18 d of adjustment to the respective dietary treatments and 3 d of sample collection. Treatments consisted of a basal diet containing a 47.11% composition of two sources of forage as follows: (1) 100% millet straw (MILLSTR), (2) 50:50 millet straw and corn straw (COMB), and (3) 100% corn straw (CORNSTR). Dry matter (DM), crude protein (CP), neutral detergent fiber (NDF), and acid detergent fiber (ADF) were tested for ruminal degradability using the nylon bag method, which was incubated for 6, 12, 24, 36, 48, and 72 h, and rumen fungal community in rumen fluid was determined by high-throughput gene sequencing technology. Ruminal pH was not affected by treatments. At 72 h, compared to MILLSTR, DM degradability of CORNSTR was 4.8% greater (p < 0.05), but when corn was combined with millet straw, the difference in DM degradability was 9.4%. During the first 24 h, degradability of CP was lower for CORNSTR, intermediate for MILLSTR, and higher for COMB. However, at 72 h, MILLSTR and COMB had a similar CP degradability value, staying greater than the CP degradability value of the CORNSTR treatment. Compared to MILLSTR, the rumen degradability of NDF was greater for CORNSTR and intermediate for the COMB. There was a greater degradability for ADF in CORNSTR, intermediate for COMB, and lower for MILLSTR. In all treatments, Ascomycota and Basidiomycota were dominant flora. Abundance of Basidiomycota in the group COMB was higher (p < 0.05) than that in the group CORNSTR at 12 h. Relative to the fungal genus level, the Thelebolus, Cladosporium, and Meyerozyma were the dominant fungus, and the abundance of Meyerozyma in COMB and CORNSTR were greater (p < 0.05) than MILLSTR at 12, 24, and 36 h of incubation. In conclusion, it is suggested to feed beef cattle with different proportions of millet straw and corn straw combinations. Full article
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8 pages, 326 KiB  
Communication
Effect of Inoculating Two Bacteriocin-Producing Lactiplantibacillus plantarum Strains at Ensiling on In Vitro Rumen Fermentation and Methane Emissions of Alfalfa Silage with Two Dry Matter Contents
by Ziqian Li, Fuhou Li, Zohreh Akhavan Kharazian and Xusheng Guo
Animals 2023, 13(3), 384; https://doi.org/10.3390/ani13030384 - 23 Jan 2023
Cited by 3 | Viewed by 1321
Abstract
The objective of this study was to investigate the effects of inoculating two bacteriocin-producing strains, Lactiplantibacillus plantarum ATCC14917 and LP1-4, at ensiling on the in vitro ruminal fermentation characteristics and methane production of alfalfa silage with two dry matter (DM)contents. Before ensiling, fresh [...] Read more.
The objective of this study was to investigate the effects of inoculating two bacteriocin-producing strains, Lactiplantibacillus plantarum ATCC14917 and LP1-4, at ensiling on the in vitro ruminal fermentation characteristics and methane production of alfalfa silage with two dry matter (DM)contents. Before ensiling, fresh alfalfa was wilted to a moderate DM content (355 g/kg) and a high DM content (428 g/kg). The wilted alfalfa was treated with (1) distilled water (control), (2) commercial strain L. plantarum MTD/1 (MTD/1), (3) bacteriocin-producing L. plantarum ATCC14917 (ATCC14917), and (4) a bacteriocin-like substance producing L. plantarum LP1-4 (LP1-4) at 1 × 105 colony forming units (CFU)/g fresh weight. After 90 d of ensiling, the silages were used for in vitro rumen fermentation. Inoculation with the two bacteriocin-producing strains at ensiling remarkably reduced (p < 0.05) in vitro ruminal CH4 production and enhanced DM digestibility compared with the control group regardless of DM content. For silages with high DM content, inoculation with the bacteriocin-producing strains even increased (p < 0.05) in vitro ruminal total volatile fatty acid production. Therefore, the bacteriocin-producing inoculants have a great potential to mitigate ruminal methane emission but without an adverse effect on rumen fermentation of the inoculated alfalfa silage. Full article
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15 pages, 1068 KiB  
Article
Effects of Different Dietary Protein Level on Growth Performance, Rumen Fermentation Characteristics and Plasma Metabolomics Profile of Growing Yak in the Cold Season
by Yanbin Zhu, Guangming Sun, Luosang Dunzhu, Xin Li, Luosang Zhaxi, Suolang Zhaxi, Suolang, Ciyang, Cidan Yangji, Basang Wangdui, Feng Pan and Quanhui Peng
Animals 2023, 13(3), 367; https://doi.org/10.3390/ani13030367 - 21 Jan 2023
Cited by 1 | Viewed by 1521
Abstract
This experiment was aimed to compare the effects of two diets with different protein content on the growth performance, immune indexes, rumen fermentation characteristics and plasma metabolomics of growing yak in the cold season. A total of 24, 2-year-old healthy yaks with similar [...] Read more.
This experiment was aimed to compare the effects of two diets with different protein content on the growth performance, immune indexes, rumen fermentation characteristics and plasma metabolomics of growing yak in the cold season. A total of 24, 2-year-old healthy yaks with similar body weight (142.9 ± 3.56 kg) were randomly allocated to two isoenergetic diets with different protein content (10 vs 14%) according to a non-paired experimental design, and the protein of the diets was increased by increasing soybean meal, rapeseed meal and cottonseed meal. The growth performance experiment lasted 56 days. Four days before the end of the growth experiment, the digestion trial was conducted, and the rumen fluid and plasma was collected for measurement. The results showed that the average daily feed intake (p < 0.001) and average daily gain (p = 0.006) of yak fed a high-protein diet was significantly greater, while the feed conversion ratio was lower (p = 0.021) than that of yaks fed a low-protein diet. Plasma aspartate aminotransferase (p = 0.002), alanine aminotransferase (p < 0.001), malondialdehyde (p = 0.001), tumor necrosis factor-α (p = 0.032) and interferon-γ (p = 0.017) of the high-protein group were significantly lesser, whereas superoxide dismutase (p = 0.004) and interleukin-2 (p = 0.007) was significantly greater than that of the low-protein group. The rumen microbial crude protein (p < 0.047) and crude protein digestibility (p = 0.015) of yak fed a high-protein diet was significantly greater than that of the low-protein group. The metabolomics results showed that yaks fed a high-protein diet were elevated in protein digestion and absorption, arginine and proline metabolism, tryptophan metabolism, purine metabolism, butanoate metabolism, taste transduction, pyrimidine metabolism, pantothenate and CoA biosynthesis, glutathione metabolism and renin secretion pathways. It is concluded that a high-protein diet in the cold season can promote rumen microbial crude protein synthesis, enhance antioxidant and immune function and promote growth performance of yaks. Full article
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18 pages, 3824 KiB  
Article
Effects of Two Different Straw Pellets on Yak Growth Performance and Ruminal Microbiota during Cold Season
by Xiangyan Wang, Bingang Shi, Zhi Zuo, Youpeng Qi, Shijie Zhao, Xueping Zhang, Lijuan Lan, Yu Shi, Xiu Liu, Shaobin Li, Jiqing Wang and Jiang Hu
Animals 2023, 13(3), 335; https://doi.org/10.3390/ani13030335 - 17 Jan 2023
Cited by 4 | Viewed by 1379
Abstract
The Tianzhu white yaks (Bos grunniens) live on the Qinghai–Tibet Plateau. During winter, a lack of resources and low nutritional levels seriously affect their growth performance. In this study, we aimed to explore the effect of supplementation straw pellets on the [...] Read more.
The Tianzhu white yaks (Bos grunniens) live on the Qinghai–Tibet Plateau. During winter, a lack of resources and low nutritional levels seriously affect their growth performance. In this study, we aimed to explore the effect of supplementation straw pellets on the growth performance and ruminal microbiota of yaks. Overall, at 6 (6M, n = 24), 18 (18M, n = 26), 30 (30M, n = 20), 42 (42M, n = 24), and 54 (54M, n = 22) month old Tianzhu white yaks were selected (total n = 116) and divided into the mixed straw + grazing (MSG), corn straw + grazing (CSG), and the grazing control (G) groups according to age and gender. Their growth performance was measured as per different dietary treatments. The rumen microbial community structure and levels of VFAs were analyzed from the 6M, 30M, and 54M male yaks from each group. The supplementary diets led to an increase in the ADG, which was the highest in the MSG group. The MSG group exhibited the highest level of acetate and total VFAs (TVFAs) among the three groups (p < 0.05). In addition, the 16S rRNA sequencing results proved that the microbial composition was dominated by the members of Firmicutes and Bacteroidetes. Christensenellaceae R-7 group was significantly abundant in the CSG and MSG groups compared to the G group (p < 0.05). Principal coordinate analysis (PCoA) revealed that the bacterial community structure of rumen in the MSG and CSG groups was considerably different from that in the G group; 6M samples exhibited different rumen microbial diversity compared with the other samples. Correlation analysis revealed that Christensenellaceae_R-7_group was positively correlated with the levels of acetate, TVFAs, and ADG. These results demonstrated that mixed straw pellets improved the growth performance of yaks, increased the abundance of Christensenellaceae R-7_group involved in cellulose degradation in the rumen, and produced large amounts of VFAs, which were absorbed by yaks, thus increasing their ADG. This study provides new insights into the effects of straw pellet supplementation on the changes in the rumen microbiota and growth performance of yaks. Full article
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13 pages, 2030 KiB  
Article
Yield, Nutritional Composition, and Digestibility of Conventional and Brown Midrib (BMR) Pearl Millet as Affected by Planting and Harvesting Dates and Interseeded Cowpea
by Madeline Oskey, Cesar Velasquez, Omar Manuel Peña, John Andrae, William Bridges, Gonzalo Ferreira and Matias Jose Aguerre
Animals 2023, 13(2), 260; https://doi.org/10.3390/ani13020260 - 12 Jan 2023
Cited by 2 | Viewed by 1284
Abstract
The objective of this study was to evaluate the yield, nutritional composition, and digestibility of conventional (CON) and brown midrib (BMR) pearl millet (PM) with different establishment dates, maturity at harvest and when mixed with cowpea (CWP). In trial 1, CON and BMR [...] Read more.
The objective of this study was to evaluate the yield, nutritional composition, and digestibility of conventional (CON) and brown midrib (BMR) pearl millet (PM) with different establishment dates, maturity at harvest and when mixed with cowpea (CWP). In trial 1, CON and BMR were planted on two different dates. In trial 2, CON and BMR, mixed or not with CWP, were harvested when PM was at the boot or heading stages. In trial 1, dry matter (DM) yield was similar between both PM genotypes but delaying establishment reduced DM yield by 30%. Additionally, BMR had a lower concentration of acid detergent lignin (ADL) and a higher in vitro neutral detergent fiber digestibility (IVNDFD) compared to CON. In Trial 2, the DM yield was 7.3% higher for CON compared to BMR, and PM with the BMR trait had a lower level of ADL and higher IVNDFD compared to CON. Mixing PM with CWP had negligible effects on nutritional composition but reduced DM yield by 8.3%. Results of these studies indicated that fiber from BMR PM is more digestible than CON but, in one of the trials, this occurred at the expense of lower DM yield. Mixing CWP with PM negatively impacted DM yield. Full article
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21 pages, 2105 KiB  
Article
Dietary Polysaccharide-Rich Extract from Noni (Morinda citrifolia L.) Fruit Modified Ruminal Fermentation, Ruminal Bacterial Community and Nutrient Digestion in Cashmere Goats
by Qingyue Zhang, Yanli Zhao, Yinhao Li, Xiaoyu Guo, Yongmei Guo, Guoqiang Ma, Xiaoshuai Liang and Sumei Yan
Animals 2023, 13(2), 221; https://doi.org/10.3390/ani13020221 - 06 Jan 2023
Cited by 2 | Viewed by 1235
Abstract
In two consecutive studies, we evaluated the effects of polysaccharide-rich noni (Morinda citrifolia L.) fruit extract (NFP) on ruminal fermentation, ruminal microbes and nutrient digestion in cashmere goats. In Exp. 1, the effects of a diet containing NFP of 0, 0.1%, 0.2%, [...] Read more.
In two consecutive studies, we evaluated the effects of polysaccharide-rich noni (Morinda citrifolia L.) fruit extract (NFP) on ruminal fermentation, ruminal microbes and nutrient digestion in cashmere goats. In Exp. 1, the effects of a diet containing NFP of 0, 0.1%, 0.2%, 0.4% and 0.55% on in vitro ruminal fermentation at 3, 6, 9, 12 and 24 h were determined, whereas in Exp. 2, fourteen cashmere goats (46.65 ± 3.36 kg of BW ± SD) were randomly assigned to two treatments: the basal diet with or without (CON) supplementation of NFP at 4 g per kg DM (0.4%). The in vitro results showed that NFP linearly increased concentrations of volatile fatty acids (VFA), quadratically decreased ammonia-N concentration, and changed pH, protozoa number, gas production and the microbial protein (MCP) concentration, and was more effective at 0.4% addition, which yielded similar results in ruminal fermentation in Exp. 2. In addition, NFP increased the apparent digestibility of dry matter and crude protein and the abundance of Firmicutes, and reduced the abundance of Bacteroides and Actinobacteria. Ruminococcus_1 was positively associated with VFA concentration. The Rikenellaceae_RC9_gut_group was positively correlated with protozoa and negatively correlated with MCP concentration. Thus, NFP has potential as a ruminal fermentation enhancer for cashmere goats. Full article
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8 pages, 1702 KiB  
Communication
Rumen Fluid Amine/Phenol-Metabolome of Beef Steers with Divergent Residual Feed Intake Phenotype
by Taylor Sidney, Godstime Taiwo, Modoluwamu Idowu, Ibukun Amusan, Andres Pech Cervantes and Ibukun Ogunade
Ruminants 2023, 3(1), 1-8; https://doi.org/10.3390/ruminants3010001 - 04 Jan 2023
Cited by 1 | Viewed by 1491
Abstract
The amine/phenol-metabolome of rumen fluid was analyzed to identify amino acid metabolism-related biomarkers associated with phenotypic selection for low or high residual feed intake (RFI) in beef cattle. Fourteen beef steers (most feed-efficient (HFE; RFI = −1.89 kg/d, n = 7) and least [...] Read more.
The amine/phenol-metabolome of rumen fluid was analyzed to identify amino acid metabolism-related biomarkers associated with phenotypic selection for low or high residual feed intake (RFI) in beef cattle. Fourteen beef steers (most feed-efficient (HFE; RFI = −1.89 kg/d, n = 7) and least feed-efficient (LFE; RFI = +2.05 kg/d, n = 7)) were selected from a total of 56 crossbred growing beef steers (average BW = 261 ± 18.5 kg) after a 49-d feeding period in a dry lot equipped with two GrowSafe intake nodes. Rumen fluid samples were collected 4 h after feeding on d 56, 63, and 70 from the HFE and LFE beef steers. Metabolome analysis of the rumen fluid was performed using chemical isotope labeling/liquid chromatography-mass spectrometry to identify all metabolites containing amine/phenol chemical groups, which are mostly amino acid metabolites. A total of 493 metabolites were detected and identified in the rumen fluid. The partial least squares discriminant scores plot showed a slight separation between the two groups of steers, and a total of eight metabolites were found to be differentially abundant (FDR ≤ 0.05). Out of the eight differentially abundant metabolites, four metabolites (isomer 1 of cadaverine, baeocystin, 6-methyladenine, and N(6)-methyllysine) qualified as candidate biomarkers of divergent RFI phenotype based on area under the curve ≥ 0.70. The results of this study revealed that divergent RFI phenotype is associated with alteration in rumen amine/phenol-metabolome of beef steers. Full article
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10 pages, 270 KiB  
Article
Effect of Dietary Inclusion of Riboflavin on Growth, Nutrient Digestibility and Ruminal Fermentation in Hu Lambs
by Na Ren, Xuanzi Zhang, Xiaoyan Hao, Yingrui Dong, Xinggang Wang and Jianxin Zhang
Animals 2023, 13(1), 26; https://doi.org/10.3390/ani13010026 - 21 Dec 2022
Cited by 1 | Viewed by 1212
Abstract
The study evaluated the influences of riboflavin (RF) supply on the growth performance, nutrient digestibility and ruminal fermentation in lambs. Forty-eight Hu lambs were randomly assigned into four groups receiving RF of 0, 15, 30 and 45 mg/kg dry mater (DM), respectively. Increasing [...] Read more.
The study evaluated the influences of riboflavin (RF) supply on the growth performance, nutrient digestibility and ruminal fermentation in lambs. Forty-eight Hu lambs were randomly assigned into four groups receiving RF of 0, 15, 30 and 45 mg/kg dry mater (DM), respectively. Increasing RF supply did not affect the DM intake, but quadratically increased the average daily gain and linearly decreased feed conversion ratio. Total-tract DM, neutral detergent fibre, acid detergent fibre and crude protein digestibility increased quadratically. Rumen pH and propionate molar percentage decreased linearly, total volatile fatty acids concentration, acetate proportion and the ratio of acetate to propionate increased linearly, but ammonia nitrogen concentration was unchanged with increasing RF supply. Linear increases were observed on the activities of carboxymethyl-cellulase, xylanase, pectinase and protease, and the populations of bacteria, fungi, protozoa, dominant cellulolytic bacteria, Ruminobacter amylophilus and Prevotella ruminicola. Methanogens population was not affected by RF supplementation. The microbial protein amount and urinary total purine derivatives excretion increased quadratically. The results indicated that 30 mg/kg DM RF supply improved growth performance, rumen fermentation and nutrient digestion in lambs. Full article
12 pages, 1800 KiB  
Article
Sex Differences in Fecal Microbiome Composition and Function of Dromedary Camels in Saudi Arabia
by Haitham Elbir and Naser Abdullah Alhumam
Animals 2022, 12(23), 3430; https://doi.org/10.3390/ani12233430 - 05 Dec 2022
Cited by 1 | Viewed by 1622
Abstract
The gastrointestinal microbiome plays a significant role in diet digestion and the energy production of its host. Several factors that affect the gastrointestinal microbiota composition were studied in camels. Yet, the impact of sex on the gastrointestinal bacteriome of camels remains unexplored to [...] Read more.
The gastrointestinal microbiome plays a significant role in diet digestion and the energy production of its host. Several factors that affect the gastrointestinal microbiota composition were studied in camels. Yet, the impact of sex on the gastrointestinal bacteriome of camels remains unexplored to date. In this perspective, the fecal microbiome community composition from dromedary camels was determined in 10 male and 10 female samples using the 16S rRNA amplicon, in order to estimate if this was influenced by sex. The core microbiome in females contained 284 bacterial OTUs and one archaeal OUT, whereas in males, it contained 279 bacterial OTUs and one archaeal OTU. In females, Bacteroidetes and Spirochaetes were significantly more abundant than in male camels, whereas Lentisphaerae and Euryarchaeota were significantly abundant in males. According to Principal Coordinate Analysis and UPGMA clustering, grouping with respect to sex was observed. The functional prediction results showed differences such as energy production and conversion, and that the cell wall/membrane/envelope were enriched in female camels. The fecal microbiome of male camels was rich in amino acid, lipid transport and metabolism. Full article
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14 pages, 286 KiB  
Article
In Vitro Rumen Fermentation and Post-Ruminal Digestibility of Sorghum–Soybean Forage as Affected by Ensiling Length, Storage Temperature, and Its Interactions with Crude Protein Levels
by Temitope Alex Aloba, Uta Dickhoefer and Joaquin Castro-Montoya
Animals 2022, 12(23), 3400; https://doi.org/10.3390/ani12233400 - 02 Dec 2022
Cited by 1 | Viewed by 1513
Abstract
The study aimed to evaluate the effects of ensiling length, storage temperature, and its interaction with crude protein (CP) levels in sorghum–soybean forage mixtures on in vitro rumen fermentation and post-ruminal digestibility of nutrients. The dietary treatments consisted of fresh forages (d 0) [...] Read more.
The study aimed to evaluate the effects of ensiling length, storage temperature, and its interaction with crude protein (CP) levels in sorghum–soybean forage mixtures on in vitro rumen fermentation and post-ruminal digestibility of nutrients. The dietary treatments consisted of fresh forages (d 0) and silages of sorghum and soybean stored indoors or outdoors for 75 and 180 d with additional ingredients to make two dietary CP levels, 90 and 130 g/kg dry matter (DM) and a forage-to-concentrate ratio of 80 to 20. An in vitro procedure was conducted using the ANKOM RF technique to study rumen fermentation. The dietary treatments were incubated in duplicate for 8 and 24 h in three runs. After each incubation time, in vitro rumen fermentation parameters were measured, and the protozoa population was counted using a microscope. Post-ruminal digestibility was determined using the pepsin and pancreatic solubility procedure. Cumulative gas production (GP) increased quadratically with ensiling length (8 h, p < 0.01; 24 h, p = 0.02), and the GP differed between CP levels at both incubation times (p < 0.01). However, total short-chain fatty acid (SCFA) concentrations in rumen inoculum increased quadratically with ensiling length (p < 0.01; for both incubation times), and interaction between ensiling length and CP levels was observed in proportions of acetate and propionate after 24 h of incubation (p < 0.01; for both incubation times). Similarly, an interaction between ensiling length and CP levels was found in the proportion of valerate after 24 h of incubation (p < 0.01). There was a quadratic response to ensiling length in the NH4–N concentration after 8 h (p < 0.01) and 24 h (p < 0.05), and the CP level also differed (p < 0.01) at both incubation times. The ciliate protozoa count after 24 h was higher in low CP diets than in high CP diets (p = 0.04). The amount of CP in the undegraded substrate at both incubation times differed between CP levels (p < 0.01; for both incubation times). An interaction effect between ensiling length and storage temperature after 8 h (p = 0.02) and 24 h (p < 0.01) was observed for intestinal CP digestibility. The effect of CP levels on intestinal CP digestibility differed after 8 h (p < 0.01) and 24 h (p < 0.01). In conclusion, increasing ensiling length beyond 75 d reduced CP digestibility, and additional CP inclusion did not ameliorate this. Full article
18 pages, 1832 KiB  
Article
Yeast Products Mediated Ruminal Subenvironmental Microbiota, and Abnormal Metabolites and Digestive Enzymes Regulated Rumen Fermentation Function in Sheep
by Manchun Su, Huihui Wang, Huibin Shi, Qiao Li, Yong Zhang, Taotao Li and Youji Ma
Animals 2022, 12(22), 3221; https://doi.org/10.3390/ani12223221 - 21 Nov 2022
Cited by 3 | Viewed by 2744
Abstract
Yeast products (YP) are commonly used as rumen regulators, but their mechanisms of action are still unclear. Based on our previous studies, we questioned whether yeast products would have an impact on rumen solid-associated (SA) and liquid-associated (LA) microorganisms and alter rumen fermentation [...] Read more.
Yeast products (YP) are commonly used as rumen regulators, but their mechanisms of action are still unclear. Based on our previous studies, we questioned whether yeast products would have an impact on rumen solid-associated (SA) and liquid-associated (LA) microorganisms and alter rumen fermentation patterns. Thirty 3-month-old male sheep weighing 19.27 ± 0.45 kg were selected and randomized into three groups for 60 days: (1) basal diet group (CON group), (2) basal diet add 20 g YP per day (low YP, LYP group) and (3) basal diet add 40 g YP per day (high YP, HYP group). The results demonstrated that the addition of YP increased rumen cellulase activity, butyrate and total volatile fatty acid (TVFA) concentrations (p < 0.05), while it decreased rumen amylase activity and abnormal metabolites, such as lactate, lipopolysaccharides (LPS) and histamine (HIS) (p < 0.05). Metagenomic analysis of rumen microorganisms in three groups revealed that YP mainly influenced the microbial profiles of the SA system. YP increased the relative abundance of R. flavefaciens and decreased methanogens in the SA system (p < 0.05). With the addition of YP, the abundance of only a few lactate-producing bacteria increased in the SA system, including Streptococcus and Lactobacillus (p < 0.05). However, almost all lactate-utilizing bacteria increased in the LA system, including Megasphaera, Selenomonas, Fusobacterium and Veillonella (p < 0.05). In addition, YP increased the abundance of certain GHs family members, including GH43 and GH98 (p < 0.05), but decreased the abundance of some KEGG metabolic pathways involved in starch and sucrose metabolism, biosynthesis of antibiotics and purine metabolism, among others. In conclusion, the addition of YP to high-concentrate diets can change the abundance of major functional microbiota in the rumen, especially in the solid fraction, which in turn affects rumen fermentation patterns and improves rumen digestibility. Full article
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8 pages, 237 KiB  
Article
Propionibacteriaium acidipropionici CP 88 Dose Alters In Vivo and In Vitro Ruminal Fermentation Characteristics
by Jonah R. Levenson, Logan Thompson, Roderick Gonzalez-Murray, Ryan J. Gifford, Meghan P. Thorndyke, Octavio Guimaraes, Huey Yi Loh, Briana V. Tangredi, Harrison Hallmark, Richard Goodall, John J. Wagner and Terry E. Engle
Ruminants 2022, 2(4), 448-455; https://doi.org/10.3390/ruminants2040031 - 04 Nov 2022
Cited by 2 | Viewed by 1521
Abstract
Twelve 5-year-old beef steers, with an average weight of 2000 lbs., fitted with rumen canulae were used in a 4 × 4 incomplete Latin square design to examine the impact of the direct fed microbial Propionibacterium acidipropionici CP 88 (PA) on rumen fermentation [...] Read more.
Twelve 5-year-old beef steers, with an average weight of 2000 lbs., fitted with rumen canulae were used in a 4 × 4 incomplete Latin square design to examine the impact of the direct fed microbial Propionibacterium acidipropionici CP 88 (PA) on rumen fermentation characteristics, in vitro CH4, CO2, and N2 production, and in vivo CH4 and CO2 production. All steers were housed in the same pen equipped with eight GrowSafe feeding stations to monitor individual animal feed intake and one GreenFeed System to estimate individual animal CH4 and CO2 production. Steers were fed a corn-silage-based diet throughout the experiment. Treatments consisted of PA administered at: (1) control (0.0); (2) 1.0 × 108; (3) 1.0 × 109; and (4) 1.0 × 1010 cfu∙animal−1∙day (d)−1. Treatments were administered directly into the rumen as a single bolus dose daily. On day 7 and 14 of each period, rumen fluid was collected from each steer 2 h post treatment administration for VFA analysis and in vitro DM digestibility determination. Following a 14 d washout period, animal treatments were switched and the experiment repeated until the 4 × 4 Latin square was complete. In vivo propionic acid molar proportions and total VFA concentrations were greater (p < 0.05) in steers receiving PA when compared with controls. All other in vivo rumen fermentation characteristics were similar across treatments. In vitro DM disappearance (p < 0.05) and total VFA (p < 0.05) were greater and CH4 lesser (p < 0.04) in fermentation vessels incubated with rumen fluid from animals receiving PA when compared with controls. Dry matter disappearance (p < 0.03) and propionic acid molar proportions increased (p < 0.04) linearly as the dose of PA increased. In vitro total VFA tended (p < 0.08) to increase linearly and CH4 production per unit of DM digested tended (p < 0.09) to decrease quadratically in response to PA dose. All other in vitro rumen fermentation characteristics were similar across treatments. These data indicate that PA impacts in vivo and in vitro rumen fermentation characteristics. Full article
13 pages, 740 KiB  
Review
Starch and Cellulose Degradation in the Rumen and Applications of Metagenomics on Ruminal Microorganisms
by Dengke Hua, Wouter H. Hendriks, Benhai Xiong and Wilbert F. Pellikaan
Animals 2022, 12(21), 3020; https://doi.org/10.3390/ani12213020 - 03 Nov 2022
Cited by 17 | Viewed by 5956
Abstract
Carbohydrates (e.g., starch and cellulose) are the main energy source in the diets of dairy cows. The ruminal digestion of starch and cellulose is achieved by microorganisms and digestive enzymes. In order to improve their digestibility, the microbes and enzymes involved in starch [...] Read more.
Carbohydrates (e.g., starch and cellulose) are the main energy source in the diets of dairy cows. The ruminal digestion of starch and cellulose is achieved by microorganisms and digestive enzymes. In order to improve their digestibility, the microbes and enzymes involved in starch and cellulose degradation should be identified and their role(s) and activity known. As existing and new analytical techniques are continuously being developed, our knowledge of the amylolytic and cellulolytic microbial community in the rumen of dairy cows has been evolving rapidly. Using traditional culture-based methods, the main amylolytic and cellulolytic bacteria, fungi and protozoa in the rumen of dairy cows have been isolated. These culturable microbes have been found to only account for a small fraction of the total population of microorganisms present in the rumen. A more recent application of the culture-independent approach of metagenomics has acquired a more complete genetic structure and functional composition of the rumen microbial community. Metagenomics can be divided into functional metagenomics and sequencing-based computational metagenomics. Both approaches have been applied in determining the microbial composition and function in the rumen. With these approaches, novel microbial species as well as enzymes, especially glycosyl hydrolases, have been discovered. This review summarizes the current state of knowledge regarding the major amylolytic and cellulolytic microorganisms present in the rumen of dairy cows. The ruminal amylases and cellulases are briefly discussed. The application of metagenomics technology in investigating glycosyl hydrolases is provided and the novel enzymes are compared in terms of glycosyl hydrolase families related to amylolytic and cellulolytic activities. Full article
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10 pages, 627 KiB  
Article
Effects of Feed Composition in Different Growth Stages on Rumen Fermentation and Microbial Diversity of Hanwoo Steers
by Chae Hwa Ryu, Han Tae Bang, Seul Lee, Byeonghyeon Kim and Youl Chang Baek
Animals 2022, 12(19), 2606; https://doi.org/10.3390/ani12192606 - 28 Sep 2022
Cited by 2 | Viewed by 1586
Abstract
Ruminants are a major source of greenhouse gas emissions, and information on ruminant fermentation and microorganisms is essential to understand ruminant digestion, which is associated with environmental pollution. The present study investigated rumen fermentation and microbial diversity according to the three different growth [...] Read more.
Ruminants are a major source of greenhouse gas emissions, and information on ruminant fermentation and microorganisms is essential to understand ruminant digestion, which is associated with environmental pollution. The present study investigated rumen fermentation and microbial diversity according to the three different growth stages of four Hanwoo steers: growing (12 months, G), early fattening (18 months, EF), and late fattening (25 months, LF). No significant differences were observed in rumen pH and ammonia nitrogen among growth stages. Total volatile fatty acids were significantly higher and propionate and valerate significantly lower in G than in EF and LF (p < 0.05). Ten bacterial phyla were detected, including Firmicutes (47.5–53.5%) and Bacteroidetes (28.4–31.7%), which accounted for 79.2–82.3% of the total bacteria. Prevotella accounted for the highest proportion (31.6–42.6%) of all bacteria in this study but did not differ significantly among the different growth stages. Metaprevotella abundance was significantly higher in G than in the other treatments (p < 0.05). In addition, Paraprevotella tended to be higher in LF than in the other treatments (p = 0.056). Given the differences in the genera of microorganisms with relatively low abundance, additional experiments are needed to determine the effect on fermentation. Full article
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14 pages, 1052 KiB  
Article
Silage Mixtures of Alfalfa with Sweet Sorghum Alter Blood and Rumen Physiological Status and Rumen Microbiota of Karakul Lambs
by Jiao Wang, Long Cheng, Abdul Shakoor Chaudhry, Hassan Khanaki, Imtiaz H. R. Abbasi, Yi Ma, Farzana Abbasi, Xuefeng Guo and Sujiang Zhang
Animals 2022, 12(19), 2591; https://doi.org/10.3390/ani12192591 - 28 Sep 2022
Cited by 2 | Viewed by 1733
Abstract
The study investigated the effects of feeding mixtures of alfalfa (AF) and sweet sorghum (SS) at different ratios of silages in terms of the physiological status of blood and rumen, and rumen microbiota in lambs. A total of 30 four-month-old male Karakul lambs [...] Read more.
The study investigated the effects of feeding mixtures of alfalfa (AF) and sweet sorghum (SS) at different ratios of silages in terms of the physiological status of blood and rumen, and rumen microbiota in lambs. A total of 30 four-month-old male Karakul lambs with 25.5 ± 1.4 kg mean initial body weight were randomly allocated to five groups, with six lambs in each group. Five experimental diets containing 40% of one of the five AF–SS mixed silages (containing 0%, 20%, 40%, 60%, and 80% AF on a fresh weight basis, respectively) and 60% of other ingredients were formulated. Overall, the results showed that the mixed silage with more AF tended to increase serum antioxidant capacity, dry matter (DM) intake, and rumen fermentation metabolites. The AF–SS mixed silages containing AF at 60% and 80% caused a significant linear increase (p < 0.05) in the activity of total antioxidant capacity. The superoxide dismutase in the Karakul lamb responded with significant linear and quadratic increases (p < 0.01) as the ratio of AF was increased in the AF–SS mixed silages. Feeding diets with AF in silage mixtures at the ratio of 60% significantly increased (p < 0.05) the concentration of ruminal total volatile fatty acids (tVFA), acetate, and ammonia-N. However, no statistical significance (p > 0.05) was found in the alpha diversity of rumen microbes among the tested groups (p > 0.05). Principal coordinates analysis could clearly discriminate the differences between the five groups (p = 0.001). The relative abundance of Firmicutes in the rumen were significantly higher with AF at 40% in the AF–SS silage-based diet than those with AF at 0%, and 20% ratios. The abundance of Ruminococcus_albus had a significant linear increase (p < 0.05), as the ratio of AF in the AF–SS mixed silages was increased. In conclusion, the best beneficial effect on the physiological status of the blood and rumen, DM intake, and rumen microbiota in lambs came from those that consumed the diet containing the AF–SS mixed silage with 60% AF. Full article
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12 pages, 492 KiB  
Article
The Effects of Breed and Residual Feed Intake Divergence on the Abundance and Active Population of Rumen Microbiota in Beef Cattle
by Yawei Zhang, Fuyong Li, Yanhong Chen and Le-Luo Guan
Animals 2022, 12(15), 1966; https://doi.org/10.3390/ani12151966 - 03 Aug 2022
Cited by 2 | Viewed by 1652
Abstract
To assess the effects of residual feed intake (RFI) and breed on rumen microbiota, the abundance (DNA) and active population (RNA) of the total bacteria, archaea, protozoa, and fungi in the rumen of 96 beef steers from three different breeds (Angus (AN), Charolais [...] Read more.
To assess the effects of residual feed intake (RFI) and breed on rumen microbiota, the abundance (DNA) and active population (RNA) of the total bacteria, archaea, protozoa, and fungi in the rumen of 96 beef steers from three different breeds (Angus (AN), Charolais (CH), and Kinsella Composite (KC)), and divergent RFIs (High vs Low), were estimated by measuring their respective maker gene copies using qRT-PCR. All experimental animals were kept under the same feedlot condition and fed with the same high-energy finishing diet. Rumen content samples were collected at slaughter and used for the extraction of genetic material (DNA and RNA) and further analysis. There was a significant difference (p < 0.01) between the marker gene copies detected for abundance and active populations for all four microbial groups. AN steers had a higher abundance of bacteria (p < 0.05) and a lower abundance of eukaryotes (protozoa and fungi, p < 0.05) compared to KC steers, while the abundance of protozoa (p < 0.05) in the AN cattle and fungi (p < 0.05) in the KC cattle were lower and higher, respectively, than those in the CH steers. Meanwhile, the active populations of bacteria, archaea, and protozoa in the KC steers were significantly lower than those in the AN and CH animals (p < 0.01). This work demonstrates that cattle breed can affect rumen microbiota at both the abundance and activity level. The revealed highly active protozoal populations indicate their important role in rumen microbial fermentation under a feedlot diet, which warrants further study. Full article
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15 pages, 325 KiB  
Article
Growth Performance, Blood Metabolites, Carcass Characteristics and Meat Quality in Finishing Wagyu Crossbred Beef Cattle Receiving Betaine–Biotin–Chromium (BBC) Supplementation
by Sukanya Poolthajit, Wuttikorn Srakaew, Theerachai Haitook, Chaiwat Jarassaeng and Chalong Wachirapakorn
Vet. Sci. 2022, 9(7), 314; https://doi.org/10.3390/vetsci9070314 - 23 Jun 2022
Viewed by 2808
Abstract
Eighteen Wagyu crossbred steers (average initial body weight: 596.9 ± 46.4 kg; average age: 36 ± 2.7 months) were subjected to three levels of betaine–biotin–chromium (BBC) supplementation for 98 days before slaughter. Animals were fed a basal diet and BBC supplemented at 0, [...] Read more.
Eighteen Wagyu crossbred steers (average initial body weight: 596.9 ± 46.4 kg; average age: 36 ± 2.7 months) were subjected to three levels of betaine–biotin–chromium (BBC) supplementation for 98 days before slaughter. Animals were fed a basal diet and BBC supplemented at 0, 3 or 6 g/kg of dry matter (DM). The experimental design was a randomized complete block design by a group of animals with six replicates. The intake and digestibility among treatments were not different (p > 0.05). The average daily gain (ADG) of steers that received BBC at 6 g/kg of DM (0.79 kg/day) tended to be higher (p = 0.07) than that of those receiving BBC at 0 and 3 g/kg/day (0.52 and 0.63 kg/day, respectively). Blood metabolites were not different (p > 0.05) among treatments. Carcass characteristic traits included chilled carcass dressing percentage and loin eye area, while meat quality included drip loss, cooking loss, and Warner-Bratzler shear force were not different (p > 0.05). Back fat thickness tended to be higher (p = 0.07) in steers fed BBC at 6 g/kg. The marbling score did not differ (p > 0.05) among treatments; however, the intramuscular fat content of the longissimus dorsi (LD) on a DM basis was significantly higher (p < 0.05) in steers fed BBC at 6 g/kg (39.8% DM) than in those fed BBC at 0 g/kg (28.2% DM) and at 3 g/kg (29.1% DM). Based on the findings, BBC supplementation had no effect on growth performance and carcass characteristics; however, BBC at 6 g/kg DM increased fat content in LD muscle of finishing Wagyu crossbred steers. Full article
13 pages, 5562 KiB  
Article
The Microbiota and Cytokines Correlation between the Jejunum and Colon in Altay Sheep
by Mengjun Ye, Meng Hou, Qimin Peng, Sheng Jia, Bin Peng, Fangfang Yin, Na Li and Jinquan Wang
Animals 2022, 12(12), 1564; https://doi.org/10.3390/ani12121564 - 17 Jun 2022
Cited by 1 | Viewed by 1584
Abstract
Both the jejunum and colon release cytokines that interact with intestinal microbiota. However, it is largely unclear which cytokines and microbial populations are involved in the homeostasis of the intestinal ecosystem for sheep health. To address this, we collected contents for isolating microbiota [...] Read more.
Both the jejunum and colon release cytokines that interact with intestinal microbiota. However, it is largely unclear which cytokines and microbial populations are involved in the homeostasis of the intestinal ecosystem for sheep health. To address this, we collected contents for isolating microbiota and tissues for determining cytokines from the jejunum and colon of 7-month-old Altay sheep. We used the techniques of 16S rRNA sequencing and ELISA to detect microbial population and cytokine level, respectively. Correlations between microbial population and cytokines were analyzed by Spearman correlation coefficient. The correlation analysis revealed higher populations of Bacteroides, Fibrobacteres and Spirochetes in the colon than in the jejunum, and IL-6 and IL-12 levels were higher in the jejunum than in the colon. Association analysis further revealed a positive association between IL-10 level and both Ruminococcus_2 and norank_f_Bifidobacteriaceae population in the jejunum. The analysis also revealed positive associations between IL-6 level and Ruminococcaceae_UCG-014 and Ruminococcaceae_UCG-013 population, IL-10 and Prevotellaceae_UCG-004, as well as TNF-α and Prevotellaceae_UCG-003 in the colon. These results indicate a potential interaction between the intestinal microbiota and the host immune system that needs to be further clarified for considering dietary formulations to maintain animal health and disease prevention. Full article
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14 pages, 1560 KiB  
Article
Effects of Concentrate Supplementation on Growth Performance, Rumen Fermentation, and Bacterial Community Composition in Grazing Yaks during the Warm Season
by Dongwen Dai, Kaiyue Pang, Shujie Liu, Xun Wang, Yingkui Yang, Shatuo Chai and Shuxiang Wang
Animals 2022, 12(11), 1398; https://doi.org/10.3390/ani12111398 - 29 May 2022
Cited by 9 | Viewed by 2017
Abstract
This study aimed to evaluate the effects of concentrate supplementation on the growth performance, serum biochemical parameters, rumen fermentation, and bacterial community composition of grazing yaks during the warm season. Eight male yaks (body weight, 123.96 ± 7.43 kg; 3-years) were randomly allocated [...] Read more.
This study aimed to evaluate the effects of concentrate supplementation on the growth performance, serum biochemical parameters, rumen fermentation, and bacterial community composition of grazing yaks during the warm season. Eight male yaks (body weight, 123.96 ± 7.43 kg; 3-years) were randomly allocated to two treatments groups: grazing (n = 4, GY) and concentrate supplement group (n = 4, GYS). Concentrate supplementation increased the average daily gain (ADG) (p < 0.05). Glucose (GLU), total protein (TP), and aspartate aminotransferase (AST) serum concentrations were significantly higher in the GYS group than in the GY group (p < 0.05). Ammonia-N, MCP: microbial protein, and total volatile fatty acid concentrations were significantly higher in the GYS group than in the GY group (p < 0.01), whereas the pH and acetate: propionate values were significantly decreased (p < 0.01). The relative abundance of Firmicutes in the rumen fluid was significantly higher in the GYS group than in the GY group (p < 0.01). At the genus level, the relative abundances of Succiniclasticum, Prevotellaceae_UCG_003, Prevotellaceae_UCG_005, and Ruminococcus_1 were significantly greater in the GY group than in the GYS group (p < 0.01). In conclusion, concentrate supplementation improved yaks’ growth potential during the warm season, improved ruminal fermentation, and altered core bacteria abundance. Full article
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