Population Of Cellulolytic Bacteria Research Articles

The impact of different management on pine-based agroforestry system and litter accumulation on the population and activity of cellulolytic bacteria

Abstract. Arfarita N, Nuraini Y, Rinady MVP, Noerhayati E, Prayogo C. 2024. The impact of different management on pine-based agroforestry system and litter accumulation on the population and activity of cellulolytic bacteria. Biodiversitas 25: 924-936. Agroforestry leads to the accumulation of organic matter, and the environmental conditions, litter quality, and decomposing organisms influence the rate at which litter decomposes. Litter decomposition in agroforestry systems is slow due to the high lignin and phenolic substances content, low light intensity, and high humidity under the canopy's shading condition. Therefore, a study was carried out to address this issue to isolate cellulolytic bacteria capable of breaking down plant litter using a qualitative cellulase activity testing method. The complete randomized block design and Tukey's test were used to determine the treatment's significance. Six agroforestry systems were examined: pine-coffee, pine-banana, pine-cardamom, pine-cardamom, mixed garden, and citrus. The PK (Pine-Coffee) plot had the highest canopy cover, litter density, and cellulolytic bacteria. The study identified three cellulolytic bacteria isolates (PK1, PK13, and PK10) from the 50 isolated bacteria of PK plot, producing the largest clear zones on CMC media. These identified isolates belonging to the Bacillus genus were Gram-positive bacteria with rod-shaped cells. The different types of litter in agroforestry systems affect the content of lignin, polyphenols, cellulose, and C/N ratios, which can influence the abundance of cellulolytic bacteria and their potential cellulase activity.

Microencapsulation of Mitragyna leaf extracts to be used as a bioactive compound source to enhance in vitro fermentation characteristics and microbial dynamics.

Mitragyna speciosa Korth is traditionally used in Thailand. They have a high level of antioxidant capacities and bioactive compounds, the potential to modulate rumen fermentation and decrease methane production. The aim of the study was to investigate the different levels of microencapsulated-Mitragyna leaves extracts (MMLE) supplementation on nutrient degradability, rumen ecology, microbial dynamics, and methane production in an in vitro study. A completely randomized design was used to assign the experimental treatments, MMLE was supplemented at 0%, 4%, 6%, and 8% of the total dry matter (DM) substrate. The addition of MMLE significantly increased in vitro dry matter degradability both at 12, 24, and 48 h, while ammonia-nitrogen (NH3-N) concentration was improved with MMLE supplementation. The MMLE had the greatest propionate and total volatile fatty acid production when added with 6% of total DM substrate, while decreased the methane production (12, 24, and 48 h). Furthermore, the microbial population of cellulolytic bacteria and Butyrivibrio fibrisolvens were increased, whilst Methanobacteriales was decreased with MMLE feeding. The results indicated that MMLE could be a potential alternative plant-based bioactive compound supplement to be used as ruminant feed additives.

The Impact of Peatland Fires on Cellulolytic Microbial Populations in Several Landuses

Studies on the impact of peatland fires on agricultural land, especially oil palm, and rubber, are still limited. This study aims to calculate the total population of cellulolytic bacteria and determine the activity of cellulolytic enzymes qualitatively in each microbial isolate found and to determine the level of peatland degradation after the fire. The research was conducted by survey in the field. The research location is in the long jungle village of Tambang Subdistrict, Kampar Regency. At the same time, the laboratory analysis was carried out in the Pathology, Entomology, and Microbiology Laboratory, Faculty of Agriculture and Animal Husbandry, Sultan Syarif Kasim Riau University. Determination of sample points using the purposive sampling method, which is to choose a location per the study's objectives at 4 locations. The first location is oil palm land that is not burnt, the second is burning oil palm land, the third is unburned rubber land, and the fourth is burned rubber land. Each location was repeated three times to obtain 12 sample points for observation. Furthermore, at each observation sample point, two soil depths were observed, 0-15 cm and 15-30 cm. The total population of cellulolytic bacteria in oil palm and rubber plantations that were burned and not burned with different soil depths ranged from 5.3 x 109 cfu / g soil to 14.0 x 109 cfu / g soil. The clear zone ratio (Z / K) of 8 cellulolytic bacterial isolates observed was high criteria, namely> 1.76 (100%). The highest Z / K ratio was produced by bacterial isolates originating from burnt rubber plantations at a soil depth of 0-15 cm, namely 5.25.

The effect of land management and organic matter inputs on bacterial population and soil nutrients across different types of agroforestry system

Abstract. Rinady MVP, Nuraini Y, Prayogo C, Arfarita N. 2023. The effect of land management and organic matter inputs on bacterial population and soil nutrients across different types of agroforestry system. Biodiversitas 24: 1333-1345. Different management of agroforestry systems changes crop composition and growth. This will affect organic matter inputs that become the source of food and energy for soil microorganisms. The soil organisms themself play an important role in amplifying soil biogeochemical processes and regulating soil reactions. This process allows the nutrients to be released into the soil and absorbed by the crop. This study aimed to examine the abundance of soil bacterial population and the changes in soil chemical properties (soil pH, total soil organic carbon (C), and total soil N (Nitrogen) under different land management and organic matter inputs. The determination of total organic C and total soil N was used by Walkey and Black and Kjedahl methods. Total Plate Count (TPC) techniques were employed to measure Total Bacteria Population (TBP) and Total Cellulolytic Bacteria (TCB). The Randomized Complete Block Design was used along with the 5% Tukey's test to examine the significant effect of the treatments. These treatments consisted of various agroforestry system as follow: (i) pine-coffee agroforestry system (PK), (ii) pine-banana agroforestry system (PPs), (iii) pine-cardamom agroforestry system (PR), (iv) pine-vegetable agroforestry system (PS), (v) mixed garden (KC), and (vi) citrus (LJ). Each treatment was repeated four times to obtain 24 experimental plots using a size of 20 m x 20 m. The results showed that the highest organic C and N content was obtained at the PK (agroforestry of pine at 41 years and coffee at 11 years old) plot, which was about 6.64% and 0.56%. Those parameters strongly correspond to the greatest soil bacteria population and soil cellulolytic bacteria population at the value of 1,71 x 105 CFU/g and 4,24 x 104 CFU/g, resulting from the greatest quantity of in-situ litter accumulation at PK plot to reach about 201.35 g. The dry weight value of litter in situ at the PK plot is greater than that of the PS and LJ plots by 81% and 87%. A power equation followed the relationship between soil organic C and the total bacteria population. A similar trend has been observed between total soil Nitrogen and total bacteria population. We concluded that changes in different management could affect soil chemical conditions and the changes in the total population of soil bacteria and cellulolytic soil bacteria.

Molecular genetic studies of microbiocenosis and microstructure of jejunum wall in young rams grown on biofortified feed additives

The research featured the effect of a diet fortified with essential microelements on the ruminal microbiota of young rams. Ruminal microbiota is largely responsible for feed digestibility and body functioning of cattle. The study involved the contents of the rumens and jejuna of seven-month-old rams of the Edilbaev breed, which were subjected to a biofortified diet. The diet included the Russian feed additives Yoddar-Zn and DAFS-25 represent a protein-carbohydrate complex with plant silicon. The microflora of the digestive tract was tested using the molecular genetic method of terminal restriction fragment length polymorphism (T-RFLP) sequestration. The microstructural studies of the jejunum samples exploited light microscopy. The feed additives increased the population of cellulolytic and lactate-fermenting bacteria, as well as the Prevotella sp. microbiome and bifidobacteria in the rumen samples. The data obtained revealed the effect of essential microelements on the taxonomic pattern of microorganisms and the microflora profile. The research revealed the ratio of normal, opportunistic, pathogenic, nonculturable, and transit microflora. The jejunum wall samples obtained from the experimental group that fed on Yoddar-Zn and DAFS-25 had a more distinct micropicture of mucous membrane. Their rumen microflora balance had fewer pathogenic and opportunistic microorganisms, which was also confirmed by the jejunum morphology. The feed additives DAFS-25 and Yoddar-Zn proved beneficial for ram diet and inhibited the negative effect of pathogenic treponemas on the rumen. The additives improved digestion, absorption, and assimilation of food nutrients, as well as increased the livestock yield.

Influence of partial replacement of alfalfa with two Salicornia forages on digestion, rumen variables, blood biochemistry metabolites and antioxidant capacity in sheep

In a completely randomized design, 24 Shall rams (average initial body weight [BW]: 43 ± 1.4 kg, aged 1.5 years) were used to evaluate the effects of partial replacement of alfalfa (Medicago sativa) hay with 2 species of Salicornia forage (i.e. bigelovii and persica) on in vivo total tract apparent digestibility, estimated microbial N synthesis (EMNS), rumen fluid parameters, blood metabolites, total antioxidant capacity (TAC) and production of methane in vitro. The three diets offered to sheep (8 per diet) prepared on a dry matter basis were 1- alfalfa hay (990 g/kg DM) + 10 g/kg DM vitamin-mineral supplement (control; AD), 2- alfalfa hay + Salicornia bigelovii (SBF) + vitamin-mineral supplement at a ratio of 690:300:10 (SBD), and 3- alfalfa hay + Salicornia persica (SPF) + vitamin-mineral supplement at a ratio of 690:300:10 (SPD). Salicornia diets did not affect DM, organic matter, crude protein or neutral detergent fiber digestibility. There was no dietary effect on in vivo ruminal pH, volatile fatty acids, or in vitro methane production. Salicornia diets increased rumen concentration of ammonia-N, total numbers of protozoa, and the population of Entodiniinae, whereas the cellulolytic bacteria population and EMNS decreased. Feeding SBD and SPD had no effect on the concentration of plasma albumin, cholesterol, glucose, total protein, triglyceride, and the albumin-globulin ratio but urea-N and TAC increased. Overall, replacing part of the alfalfa hay ration with SBF or SPF improved TAC in sheep with no negative effects on nutrient digestibility or in vitro methane production. This trial showed that Salicornia could be used as a partial substitute for conventional forage in the diet of sheep.

A greener way of lactic acid production from cellulose-rich waste materials utilising cellulolytic bacteria population from insect gut

The lactic acid production potential of cellulosic wastes was tested through SSF using insect gut cellulose-degrading bacteria population isolated from Derobrachus hovorei (Dhb), Omocestus viridulus (Ovb), and Spilosoma virginica (Svb). SSF was carried out using Lactobacillus acidophilus (LAB) and insect gut cellulosic bacteria at 1:1 at different temperatures (30°, 37°, and 45 °C), pH (4.5, 5, and 6) and fermentation periods (24, 48, 60, and 72 h). The present study found that the optimum operational parameters for lactic acid fermentation vary with the substrate and microbial sources used. From 1% substrate used, the statistically highest lactic acid concentration for Sugarcane bagasse (16.20%), Water hyacinth (14.75%) and Grass (14.20%) was obtained after 72 h of fermentation at 30 °C and pH 5 using LAB + Ovb, LAB + Svb and LAB + Dhb, respectively. However, there were no significant differences in produced lactic acid from cellulosic wastes at constant operational parameters and microbial sources.

Effects of zinc sulfate and coated zinc sulfate on lactation performance, nutrient digestion and rumen fermentation in Holstein dairy cows

This study was to evaluate impacts of zinc sulfate (ZS) and coated ZS (CZS) supplementation on milk performance, nutrient digestibility and rumen fermentation. Forty-five Holstein dairy cows were assigned in a randomized block design to one of five treatments: control, ZS supplementation (30 mg Zn/kg dry matter [DM] as ZS) or CZS supplementation (10, 20 and 30 mg Zn/kg DM as CZS for LCZS, MCZS and HCZS, respectively). The experiment lasted for 110 days with 20 days for adaptation and 90 days for data collection. When comparing Zn source at same supplemental level (30 mg Zn/kg DM), milk yield and total-tract digestibility of neutral detergent fibre (NDF) and acid detergent fibre (ADF) tended to be higher and ruminal activities of xylanase, cellobiase, pectinase and protease and serum alkaline phosphatase (ALP) were higher for HCZS than for ZS. Increasing CZS addition linearly increased DM intake and yields of milk, milk fat and milk protein but did not affect milk lactose yield, milk composition content and feed efficiency. Digestibility of DM, organic matter, crude protein, NDF and ADF, ruminal total volatile fatty acids content and acetate to propionate ratio linearly increased but ammonia N content linearly decreased with increasing CZS addition. Quadratic responses were observed for proportions of acetate and propionate. Activities of cellulase and protease and populations of total bacteria, fungi, protozoa, dominant cellulolytic and amylolytic (proteolytic) bacteria responded linearly and positively with increasing CZS addition. Increasing CZS addition linearly increased liver Zn and blood total protein, albumin, ALP and Zn. Results indicated that CZS could be used as a Zn supplement in cows, and supplementing 20 or 30 mg/kg DM of Zn from CZS stimulated performance, nutrients digestion and ruminal fermentation and improved Zn status in cows fed diets containing 31.2 mg Zn/kg DM.

Guanidinoacetic acid and betaine supplementation have positive effects on growth performance, nutrient digestion and rumen fermentation in Angus bulls

This study evaluated the influences of guanidinoacetic acid (GAA) and betaine (BT) on growth performance, nutrient digestion and ruminal fermentation in bulls. Forty-four Angus bulls were blocked by live body weight and then randomly divided into four groups in a 2 × 2 factorial design. Betaine of 0 or 0.6 g/kg dry matter (DM) was added to diets containing 0 or 0.6 g/kg DM GAA, respectively. The experiment included a 20 day period for adaptation and a 60 day period for data collection. Average daily gain and feed efficiency were increased by GAA or BT but no further increase was observed for supplementing BT and GAA together than for addition with BT or GAA alone. Supplementary GAA or BT did not influence DM intake but increased apparent digestibility of DM, organic matter (OM), crude protein (CP) and acid detergent fibre (ADF). Digestibility of neutral detergent fibre (NDF) was increased by GAA inclusion but was unaltered with BT provision. Ruminal pH reduced but total volatile fatty acids and ammonia nitrogen elevated with dietary inclusion of GAA or BT. Rumen short chain fatty acids percentages and fermentation pattern were not influenced by GAA. Dietary inclusion of BT increased molar proportions of acetate, valerate, isobutyrate and isovalerate as well as the ratio of acetate to propionate. Rumen populations of Ruminococcus flavefaciens and Fibrobacter succinogenes increased with addition of GAA or BT and the increase was greater when BT was added in diets with GAA compared to diets without GAA. Addition of GAA or BT increased activities of cellobiase, xylanase, α-amylase and protease and populations of total bacteria, cellulolytic bacteria and Ruminobacter amylophilus but did not affect Prevotella ruminicola. Addition of BT increased carboxymethyl-cellulase and pectinase activities and total fungi population. Blood creatine content was increased by GAA or BT and was greater for addition of GAA and BT together than for GAA or BT addition alone. Serum contents of glucose, folate, arginine and methionine were unchanged but total protein increased with GAA or BT provision. Blood homocysteine content was unaffected by GAA but decreased with BT supplementation. The data showed that GAA or BT addition improved growth performance and feed efficiency but supplementing GAA and BT together did not further increase the performance of bulls when compared with GAA or BT inclusion alone.

Efek suplementasi tepung kulit jengkol pada pelepah sawit fermentasi terhadap profil mikroba rumen dan produksi gas metan in vitro

<p class="MDPI17abstract"><strong>Objective: </strong>This research was aimed to evaluation the effect of supplementation jengkol peel powder in fermented oil palm fronds on rumen microbes profile and methane production on <em>in vitro</em>.</p><p class="MDPI17abstract"><strong>Methods: </strong>The used design was factorial randomized block design with four treatments supplementation of jengkol peel powder at 0, 2, 4, and 6% and four groups as replications. The observed variables were rumen microbes profile (population of total bacteria, cellulolytic, and protozoa), methane production, partial <em>volatile fatty acid</em> (VFA) proportion and acetate/propionate (A/P) ratio. The data were analyzed using ANOVA and different among treatments means examined by Duncan Multiple Range Test (DMRT).<strong></strong></p><p class="MDPI17abstract"><strong>Results: </strong>The result showed that supplementation of jengkol peel powder at 6% substrate increased (P<0.05) total and cellulolytic bacteria population. Jengkol peel powder supplementation as much as 4 and 6% decreased (P<0.05) protozoa population, methane production, acetate proportion and A/P ratio. Supplementation of jengkol peel powder at 2% increased (P<0.05) propionate production.<strong></strong></p><p class="MDPI17abstract"><strong>Conclusions: </strong>In conclusion, fermented oil palm fronds can be substituted with jengkol peel powder at 2% substrate that did not disturb rumen microbes profile, decreased methane production, acetate proportion, A/P ratio and increased propionate production on <em>in vitro</em>.<strong></strong></p>

Feeding a Negative Dietary Cation-Anion Difference to Female Goats Is Feasible, as Indicated by the Non-Deleterious Effect on Rumen Fermentation and Rumen Microbial Population and Increased Plasma Calcium Level.

Simple SummaryDiets with a lower dietary cation-anion difference could prevent hypocalcemia, enhance health, and extend the economic life of transition mammary animals. However, there is less information on rumen fermentation, cellulolytic bacteria populations, and microbiota for female goats fed a negative dietary cation-anion difference diet. We speculate that a negative dietary cation-anion difference would not affect the rumen fermentation parameters. Therefore, the present study was conducted to evaluate the effect of a negative dietary cation-anion difference diet on rumen pH, buffering capability, volatile fatty acids of acetic acid, propionic acid, butyric acid, total volatile fatty acid and acetic acid/propionic acid profiles, ruminal cellulolytic bacteria populations, and microbiota. These results provide a further evaluation on the feasibility of feeding a negative dietary cation-anion difference diet to goats.The dietary cation-anion difference (DCAD) has been receiving increased attention in recent years; however, information on rumen fermentation, cellulolytic bacteria populations, and microbiota of female goats fed a negative DCAD diet is less. This study aimed to evaluate the feasibility of feeding a negative DCAD diet for goats with emphasis on rumen fermentation parameters, cellulolytic bacteria populations, and microbiota. Eighteen female goats were randomly blocked to 3 treatments of 6 replicates with 1 goat per replicate. Animals were fed diets with varying DCAD levels at +338 (high DCAD; HD), +152 (control; CON), and −181 (low DCAD; LD). This study lasted 45 days with a 30-d adaption and 15-d trial period. The results showed that the different DCAD levels did not affect the rumen fermentation parameters including pH, buffering capability, acetic acid, propionic acid, butyric acid, sum of acetic acid, propionic acid, and butyric acid, or the ratio of acetic acid/propionic acid (p > 0.05). The 4 main ruminal cellulolytic bacteria populations containing Fibrobacter succinogenes, Ruminococcus flavefaciens, Butyrivibrio fibrisolvens, and Ruminococcus albus did not differ from DCAD treatments (p > 0.05). There was no difference in bacterial richness and diversity indicated by the indices Chao, Abundance Coverage-based Estimator (Ace), or Simpson and Shannon, respectively (p > 0.05), among 3 DCAD levels. Both principal coordinate analysis (PCoA) weighted UniFrac distance and unweighted UniFrac distance showed no difference in the composition of rumen microbiota for CON, HD, and LD (p > 0.05). At the phylum level, Bacteroidetes was the predominant phylum followed by Firmicutes, Synergistetes, Proteobacteria, Spirochaetae, and Tenericutes, and they showed no difference (p > 0.05) in relative abundances except for Firmicutes, which was higher in HD and LD compared to CON (p < 0.05). At the genus level, the relative abundances of 11 genera were not affected by DCAD treatments (p > 0.05). The level of DCAD had no effect (p > 0.05) on growth performance (p > 0.05). Urine pH in LD was lower than HD and CON (p < 0.05). Goats fed LD had higher plasma calcium over HD and CON (p < 0.05). In summary, we conclude that feeding a negative DCAD has no deleterious effects on rumen fermentation and rumen microbiota and can increase the blood calcium level, and is therefore feasible for female goats.

Supplementation of Prill Fat Derived from Palm Oil on Nutrient Digestibility and Dairy Cow Performance

Prill fat is a hydrogenated vegetable oil which contains more than 85% palmitic acid with a high melting point. Due to this reason, it does not melt at rumen temperature and bypass rumen degradation. This study was aimed to determine the optimum level of prill fat (86% palmitic acid) supplementation in dairy ration on fermentation characteristics, feed digestibility, milk production, milk components and milk fatty acid profiles. In vitro analysis used Randomized Block Design with 4 treatments and 4 replications and the in vivo analysis using T-Test. The in vitro result showed prill fat supplementation was significantly affected the total Volatile Fatty Acids (VFA) concentration (p<0.05). The addition of prill fat significantly decreased dry matter and organic matter digestibility (p<0.01), Neutral Detergent Fiber (NDF) and Acid Detergent Fiber (ADF) digestibility (p<0.05), total protozoa biomass (p<0.01) and population of cellulolytic bacteria (p<0.05). Furthermore, supplementation of prill fat in the level of 2% had no effect on pH, ammonia (NH3)N concentration and total rumen bacteria activity. The prill fat treatment at the level of 2% had no effect on dry matter intake, milk component and milk yield on in vivo analysis. In addition, milk yield, milk component and milk fatty acids were elevated after the prill fat treatment. This research concluded, the optimum level of prill fat addition in dairy ration was at the level of 2%. Supplementation of prill fat had no effect on rumen fermentation and fiber digestibility. Prill fat supplementation can be used to augment the milk yield, milk component, fatty acid composition in milk and had no effect on Atherogenicity Index (AI) and Hypocholesterolemic/Hypercholesterolemic (HH).

Potential of Mulberry Leaf Biomass and Its Flavonoids to Improve Production and Health in Ruminants: Mechanistic Insights and Prospects.

Simple SummaryThe economics of livestock production depends upon the feasible feeding resources as feed costs constitute more than 70% of the total expenses of a livestock enterprise. In this regard, searching for alternative and cheaper feeding resources is imperative for economical and sustainable livestock production. Mulberry leaves are an important resource available for feeding livestock, as they possess quite high protein and energy contents as compared to other tree leaves and conventional forages. Moreover, polyphenolic compounds (mainly flavonoids) present in mulberry leaf (ML) possess excellent antioxidant and antimicrobial potential that can beneficially impact animal health and production. Mulberry leaves and its flavonoids have been shown to increase the feed digestibility and milk production in ruminants, while reducing methane emission. Moreover, mulberry flavonoids can positively influence body metabolism and alleviate oxidative stress in animals. This review highlights the importance of this unique feeding resource for ruminants to increase their performance while reducing methane emissions.Leaf biomass from the mulberry plant (genus Morus and family Moraceae) is considered a potential resource for livestock feeding. Mulberry leaves (MLs) contain high protein (14.0–34.2%) and metabolizable energy (1130–2240 kcal/kg) with high dry matter (DM) digestibility (75–85%) and palatability. Flavonoid contents of MLs confer unique antioxidant properties and can potentially help alleviate oxidative stress in animals during stressful periods, such as neonatal, weaning, and periparturient periods. In addition, mulberry leaf flavonoids (MLFs) possess antimicrobial properties and can effectively decrease the population of ruminal methanogens and protozoa to reduce enteric methane (CH4) production. Owing to its rich flavonoid content, feeding MLs increases fiber digestion and utilization leading to enhanced milk production in ruminants. Dietary supplementation with MLFs alters ruminal fermentation kinetics by increasing total volatile fatty acids, propionate, and ammonia concentrations. Furthermore, they can substantially increase the population of specific cellulolytic bacteria in the rumen. Owing to their structural homology with steroid hormones, the MLFs can potentially modulate different metabolic pathways particularly those linked with energy homeostasis. This review aims to highlight the potential of ML and its flavonoids to modulate the ruminal microbiome, fermentation, and metabolic status to enhance productive performance and health in ruminants while reducing CH4 emission.

Levels of the Enterolobium cyclocarpum pod in feedlot diet on growth performance, ruminal fermentation and biogas production of lambs-hair

Enterolobium cyclocarpum (Ec) is a native legume that grows from southern Mexico to South America; its seeds are traditionally used for feeding ruminants. The objective of this study was to evaluate the addition of Ec pods in diets of hair lambs and their effect on the productive variables, ruminal fermentation and in vitro production of methane (CH4) and carbon dioxide. Thirty male lambs fed diets containing 0% (Ec0), 20% (Ec20) and 40% (Ec40) based on dry matter were evaluated. The addition of Ec40 in the integral diet of the lambs did not affect the growth performance. The pH of the ruminal fluid did not show differences between the treatments. The addition of Ec40 increased propionate and decreased acetate. Protozoa decreased in 47 and 59% with Ec20 and Ec40, respectively; while the population of cellulolytic bacteria decreased with Ec40. In vitro degradability of dry matter was lower in 8.8% with the inclusion of Ec40 in diets. The novelty of the study was that Ec40 diet decreased the ruminal methane production.

Effects of copper sulphate and coated copper sulphate addition on lactation performance, nutrient digestibility, ruminal fermentation and blood metabolites in dairy cows.

Coated copper sulphate (CCS) could be used as a Cu supplement in cows. To investigate the influences of copper sulphate (CS) and CCS on milk performance, nutrient digestion and rumen fermentation, fifty Holstein dairy cows were arranged in a randomised block design to five groups: control, CS addition (7·5 mg Cu/kg DM from CS) or CCS addition (5, 7·5 and 10 mg Cu/kg DM from CCS, respectively). When comparing Cu source at equal inclusion rates (7·5 mg/kg DM), cows receiving CCS addition had higher yields of fat-corrected milk, milk fat and protein; digestibility of DM, organic matter (OM) and neutral-detergent fibre (NDF); ruminal total volatile fatty acid (VFA) concentration; activities of carboxymethyl cellulase, cellobiase, pectinase and α-amylase; populations of Ruminococcus albus, Ruminococcus flavefaciens and Fibrobacter succinogenes; and liver Cu content than cows receiving CS addition. Increasing CCS addition, DM intake was unchanged, yields of milk, milk fat and protein; feed efficiency; digestibility of DM, OM, NDF and acid-detergent fibre; ruminal total VFA concentration; acetate:propionate ratio; activity of cellulolytic enzyme; populations of total bacteria, protozoa and dominant cellulolytic bacteria; and concentrations of Cu in serum and liver increased linearly, but ruminal propionate percentage, ammonia-N concentration, α-amylase activity and populations of Prevotella ruminicola and Ruminobacter amylophilus decreased linearly. The results indicated that supplement of CS could be substituted with CCS and addition of CCS improved milk performance and nutrient digestion in dairy cows.

Liquid hot water treatment of rice straw enhances anaerobic degradation and inhibits methane production during in vitro ruminal fermentation

Liquid hot water (LHW) treatment can be used to disrupt the fiber structure of rice straw. This in vitro ruminal batch culture study investigated the effect of LHW treatment on feed degradation, methane (CH4) production, and microbial populations. Rice straw was treated by LHW, and in vitro ruminal fermentation was performed using an automatic system with 72 h of incubation. Scanning electron microscopy showed that LHW treatment disrupted the physical structure of rice straw. Liquid hot water treatment decreased neutral detergent fiber and hemicellulose contents of the rice straw and increased neutral detergent solubles, water-soluble carbohydrates, and arabinose contents. Liquid hot water treatment increased dry matter degradation and volatile fatty acid concentration and decreased the acetate:propionate ratio, CH4 production, hydrogen accumulation, neutral detergent fiber degradation, and populations of protozoa, fungi, and cellulolytic bacteria. In summary, LHW treatment disrupted the cellulose-hemicellulose-lignin structure matrix of rice straw, leading to increased substrate degradability and decreased CH4 production. Therefore, the LHW treatment is a potential strategy to improve the nutritive value of forage such as rice straw and decrease the CH4 emissions in ruminants.

The effect of lactic acid bacteria inoculums on in vitro rumen fermentation, methane production, ruminal cellulolytic bacteria populations and cellulase activities of corn stover silage

The objective of this study was to investigate the effect of lactic acid bacteria (LAB) inoculums on fermentation quality and in vitro digestibility of corn stover silage. Corn stover was ensiled without (control) or with Lactobacillus plantarum (LP), Enterococcus faecalis (EF), and Enterococcus mundtii (EM) for 45 days. The fermentation characteristics were assessed, and subsequent in vitro dry matter digestibility (DM-D), neutral detergent fiber digestibility (NDF-D), volatile fatty acids (VFA), methane (CH4) production, cellulolytic bacteria proportions and their activities per corn stover silage were also determined. There was no significant difference (P>0.05) among the silage pH, lactic acid, crude protein (CP), water soluble carbohydrates (WSC) and lignocelluloses contents of different treatments. The relative proportions of Ruminococcus flavefaciens and Fibrobacter succinogenes, carboxymethyl-ocellulose and β-glycosidase activities, DM-D, NDF-D, and VFA production of in vitro incubation was higher (P<0.05) for silages inoculated with LP and EF than those of the control silage. Silage inoculated with LP showed the lowest (P<0.05) CH4 production per unit yield of VFA, which was positively corresponded to the lowest (P<0.05) ratio of acetate to propionate. In summary, the ensiling fermentation quality and subsequent utilization of corn stover silage were efficiently improved by inoculated with L. plantarum.

Effects of soybean oil and dietary copper levels on nutrient digestion, ruminal fermentation, enzyme activity, microflora and microbial protein synthesis in dairy bulls

ABSTRACT The study evaluated the effects of soybean oil (SO) and dietary copper levels on nutrient digestion, ruminal fermentation, enzyme activity, microflora and microbial protein synthesis in dairy bulls. Eight Holstein rumen-cannulated bulls (14 ± 0.2 months of age and 326 ± 8.9 kg of body weight) were allocated into a replicated 4 × 4 Latin square design in a 2 × 2 factorial arrangement with factors being 0 or 40 g/kg dietary dry matter (DM) of SO and 0 or 7.68 mg/kg DM of Cu from copper sulphate (CS). The basal diet contained per kg DM 500 g of corn silage, 500 g of concentrate, 28 g of ether extract (EE) and 7.5 mg of Cu. The SO × CS interaction was significant (p < 0.05) for ruminal propionate proportion and acetate to propionate ratio. Dietary SO addition increased (p < 0.05) intake and total tract digestibility of EE but did not affect average daily gain (ADG) of bulls. Dietary CS addition did not affect nutrient intake but increased (p < 0.05) ADG and total tract digestibility of DM, organic matter, crude protein and neutral detergent fibre. Ruminal pH was not affected by treatments. Dietary SO addition did not affect ruminal total volatile fatty acids (VFA) concentration, decreased (p < 0.05) acetate proportion and ammonia N and increased (p < 0.05) propionate proportion. Dietary CS addition did not affect ammonia N, increased (p < 0.05) total VFA concentration and acetate proportion and decreased (p < 0.05) propionate proportion. Acetate to propionate ratio decreased (p < 0.05) with SO addition and increased (p < 0.05) with CS addition. Dietary SO addition decreased (p < 0.05) activity of carboxymethyl cellulase, cellobiase and xylanase as well as population of fungi, protozoa, methanogens, Ruminococcus albus and R. flavefaciens but increased (p < 0.05) α-amylase activity and population of Prevotella ruminicola and Ruminobacter amylophilus. Dietary CS addition increased (p < 0.05) activity of cellulolytic enzyme and protease as well as population of total bacteria, fungi, protozoa, methanogens, primary cellulolytic and proteolytic bacteria. Microbial protein synthesis was unchanged with SO addition but increased (p < 0.05) with CS addition. The results indicated that the addition of CS promoted nutrient digestion and ruminal fermentation by stimulating microbial growth and enzyme activity but did not relieve the negative effects of SO addition on ruminal fermentation in dairy bulls.

Fermentation quality and in vitro digestibility of first and second cut alfalfa (Medicago sativa L.) silages harvested at three stages of maturity

To investigate the suitable harvest stage of alfalfa for ensiling, first cut or second cut alfalfa were harvested at the budding stage (BS), the initial flowering stage (IFS) and the full flowering stage (FFS) in 2016 and 2017, and they were then ensiled for 45 days. The nutritional value and fermentation characteristics were assessed; subsequent in vitro gas production, digestibility, ruminal fermentation parameters, and cellulolytic bacteria populations and their activities per alfalfa silage were also determined. The results showed that the silage dry matter (DM), neutral detergent fibre (NDF) and acid detergent fibre (ADF) contents increased (P < 0.01), and crude protein content decreased (P = 0.005) with advancing maturity of the alfalfa. In first cut silage, the BS had the lowest (P < 0.05) pH and the highest (P < 0.05) asymptotic gas volume, dry matter digestibility (DMD), neutral detergent fibre digestibility (NDFD) and total volatile fatty acid (VFA) production in vitro among the three treatments. In second cut silage, the silage pH, ammonia nitrogen (NH3-N), acetic acid and butyric acid contents decreased (P < 0.05) with advancing maturity, but the IFS had the highest asymptotic gas volume, DMD and NDFD among the three treatments; the proportions of Fibrobacter succinogenes, Butyrivibrio fibrisolvens and Ruminobacter flavefacien and carboxymethyl-cellulase and β-glycosidase activities of in vitro incubation fluid were higher for the IFS compared with those of the BS. In conclusion, based on the nutritional value, fermentation characteristics and subsequent in vitro rumen digestibility of alfalfa silage, the best harvest stage of the first cut and second cut alfalfa were at BS and IFS, respectively. At the same maturity stage, the first cut alfalfa silage was better than the second cut silage.

Structural diversity and efficacy of culturable cellulose decomposing bacteria isolated from rice-pulse resource conservation practices.

The diversity of cellulolytic bacteria from the rice-pulse system can be sourced for identification of efficient cellulose decomposing microbial strains. In the present study, the abundance, structural diversity, and cellulolytic potential of the culturable bacterial community were studied in 5-year old rice-pulse system under different resource conservation technologies. Higher cellulose (68% more) and xylanase (35% more) activities were observed under zero tilled soil. The populations of cellulolytic bacteria were significantly higher (44%) in zero tillage (ZT) treatment than those of conventional practice. Results revealed that the cellulolytic bacterial diversity was found to be significantly higher under ZT practice, but the present population may not be sufficient for effective recycling of organic wastes in this system. Out of 290 bacterial isolates, 20 isolates had significantly higher cellulolytic activities, of which the top three superior isolates were received from ZT practice. The cellulolytic bacterial diversity based on 16S rDNA sequencing data revealed that the Firmicutes was the most dominant phyla and the Bacillus spp. were the common genus, the observation also showed that there were 17 different haplotypes were recorded among 20 isolates of cellulolytic bacteria. The present findings indicated that long-term ZT in the rice-pulse system could be a unique source for efficient cellulose decomposing bacteria and further the efficient bacterial strains isolated from this system can be used as efficient bioinoculants for in situ as well as ex-situ decomposition of rice straw particularly in conservation agriculture.