• Asian-Australasian Journal of Animal Sciences
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• 제29권10호
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• pp.1416-1423
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• 2016

This study was designed to investigate the effect of grape pomace powder (GPP), mangosteen peel powder (MPP) and monensin on feed intake, nutrients digestibility, microorganisms, rumen fermentation characteristic, microbial protein synthesis and nitrogen balance in dairy steers. Four, rumen fistulated dairy steers with initial body weight (BW) of $220{\pm}15kg$ were randomly assigned according to a $4{\times}4$ Latin square design to receive four treatments. The treatments were as follows: T1 = control, T2 = supplementation with monensin at 33 mg/kg diet, T3 = supplementation with GPP at 2% of dry matter intake, and T4 = supplementation with MPP at 30 g/kg diet. The steers were offered the concentrate diet at 0.2% BW and 3% urea treated rice straw (UTRS) was fed ad libitum. It was found that GPP supplemented group had higher UTRS intake and nutrient digestibility in terms of neutral detergent fiber and acid detergent fiber than those in control group (p<0.05). Ammonia nitrogen ($NH_3-N$) and blood urea-nitrogen concentration were higher in monensin, GPP and MPP supplemented groups (p<0.05). Total volatile fatty acids and propionate in the GPP group were higher than those in the control group (p<0.05) while acetate concentration, and acetate to propionate ratio were decreased (p<0.01) when steers were supplemented with GPP, monensin, and MPP, respectively. Moreover, protozoal populations in GPP, MPP, and monensin supplementation were significantly lower than those in the control group (p<0.05), while cellulolytic bacterial population was significantly higher in the control group (p<0.05). Nitrogen retention, microbial crude protein and efficiency of microbial nitrogen synthesis were found significantly higher in steers that received GPP (p<0.05). Based on this study it could be concluded that the GPP has potential as an alternative feed supplement in concentrate diets which can result in improved rumen fermentation efficiency, digestibility and microbial protein synthesis in steers fed on treated rice straw.

• Asian-Australasian Journal of Animal Sciences
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• 제17권10호
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• pp.1400-1410
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• 2004

Eight crossbred (75% Holstein Friesian) cows in mid-lactation were randomly assigned to a switchback design with a 2x2 factorial arrangement to evaluate two nonstructural carbohydrate (NSC) sources (corn meal and cassava chips) with different rumen degradability and used at two levels of NSC (55 vs. 75%) with protein source (supplied by urea in the concentrate mix). The treatments were 1) Low degradable low level of corn (55%) 2) Low degradable high level of corn (75%) 3) High degradable low level of cassava (55%) and 4) High degradable high level of cassava (75%). The cows were offered the treatment concentrate at a ratio to milk yield at 1:2. Urea-treated rice straw was offered ad libitum as the roughage and supplement with 1 kg/hd/d cassava hay. The results revealed that total DM intake, BW and digestion coefficients of DM were not affected by either level or source of energy. Rumen fermentation parameters; NH3-N, blood urea nitrogen and milk urea nitrogen were unaffected by source of energy, but were dramatically increased by level of NSC. Rumen microorganism populations were not affected (p>0.05) by source of energy, but fungal zoospores were greater for cassava-based concentrate than corn-based concentrate. Milk production and milk composition were not affected significantly by diets containing either source or level of NSC, however concentrate than corn-based concentrate averaging (4.4 and 4.2, respectively). Likewise, income over feed, as estimated from 3.5% FCM, was higher on cassava-based concentrate than corn-based concentrate averaging (54.0 and 51.4 US$/mo, respectively). These results indicate that feeding diets containing either cassava-based diets and/or a higher of oncentrates up to 75% of DM with NPN (supplied by urea up to 4.5% of DM) can be used in dairy rations without altering rumen ecology or animal performance compared with corn-based concentrate.

• Asian-Australasian Journal of Animal Sciences
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• 제31권8호
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• pp.1205-1212
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• 2018

Objective: The aim of this experiment was to evaluate the effects of different dietary ratio of metabolizable glucose (MG) to metabolizable protein (MP) on growth performance, blood metabolites, rumen fermentation parameters and the ruminal microbial community of 8 to 10-month-old heifers. Methods: A total of 24 Holstein heifers weighing an average of 282.90 kg (8 month of age) were randomly assigned to four groups of six. The heifers were fed one of four diets of different dietary MG/MP (0.97, 1.07, 1.13, and 1.26). Results: The results showed that the ratio of MG/MP affected the growth performance, blood metabolites, rumen fermentation parameters and the ruminal microbial community of heifers. The average daily gain of heifers was enhanced by increasing the ratio of MG/MP (p<0.05). The concentration of blood urea nitrogen, cholesterol, and low density lipoprotein cholesterol as well as the concentration of total volatile fatty acid in the rumen fluid of heifers decreased with the improvement in the ratio of dietary MG/MP (p<0.05). However, the relative amount of Ruminococcus albus and Butyrivibrio fibrisolvens in the rumen of heifers was increased significantly (p<0.05) when the dietary MG/MP increased. At the same time, with the improvement in dietary MG/MP, the amount of Fibrobacter succinogenes increased (p = 0.08). Conclusion: A diet with an optimal ratio (1.13) of MG/MP was beneficial for the improvement of growth, rumen fermentation, dietary protein and energy utilization of 8 to 10-month-old dairy heifers in this experiment.

• Asian-Australasian Journal of Animal Sciences
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• 제2권3호
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• pp.454-455
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• 1989

• Asian-Australasian Journal of Animal Sciences
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• 제14권6호
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• pp.797-802
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• 2001

Two strains of rumen fungi (Piromyces rhizinflata B157, Orpinomyces joyonii SG4) and three strains of rumen cellulolytic bacteria (Ruminococcus albus B199, Ruminococcus flavefaciens FD1 and Fibrobacter succinogenes S85) were used as mono-cultures or combinationally arranged as co- and sequential-cultures to assess the relative contributions and interactions between rumen fungi and cellulolytic bacteria on rice straw degradation. The rates of dry matter degradation of co-cultures were similar to those of corresponding bacterial mono-cultures. Compared to corresponding sequential-cultures, the degradation of rice straw was reduced in all co-cultures (P<0.01). Regardless of the microbial species, the cellulolytic bacteria seemed to inhibit the degradation of rice straw by rumen fungi. The high efficiency of fungal cellulolysis seems to affect bacterial degradation rates.

• Asian-Australasian Journal of Animal Sciences
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• 제13권1호
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• pp.96-114
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• 2000

Genetically selected beef cattle are fed high-energy diets in intensive production systems developed in industrial countries. This type of feeding can induce rumen dysfunctions that have to be corrected by farmers to optimise cost-effectiveness. The risk of rumen acidosis can be reduced by using slowly degradable starch, which partly escapes rumen fermentation and goes on to be digested in the small intestine. Additives are proposed to stabilise the rumen pH and restrict lactate accumulation, thus favouring the growth of cellulolytic bacteria and stimulating the digestion of the dietary plant cell wall fraction. This enhances the energy value of feeds when animals are fed maize silage for example. Supplementation of lipids to increase energy intake is known to influence the population of rumen protozoa and some associated rumen functions such as cellulolysis and proteolysis. The end products of rumen fermentation are also changed. Lipolysis and hydrogenation by rumen microbes alter the form of fatty acids supplied to animals. This effect is discussed in relation with the quality of lipids in beef and the implications for human health. Conditions for optimising the amount of amino acids from microbial proteins and dietary by-pass proteins flowing to the duodenum of ruminants, and their impact on beef production, are also examined.

• Journal of Microbiology and Biotechnology
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• 제32권3호
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• pp.269-277
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• 2022

Human activities account for approximately two-thirds of global methane emissions, wherein the livestock sector is the single massive methane emitter. Methane is a potent greenhouse gas of over 21 times the warming effect of carbon dioxide. In the rumen, methanogens produce methane as a by-product of anaerobic fermentation. Methane released from ruminants is considered as a loss of feed energy that could otherwise be used for productivity. Economic progress and growing population will inflate meat and milk product demands, causing elevated methane emissions from this sector. In this review, diverse approaches from feed manipulation to the supplementation of organic and inorganic feed additives and direct-fed microbial in mitigating enteric methane emissions from ruminant livestock are summarized. These approaches directly or indirectly alter the rumen microbial structure thereby reducing rumen methanogenesis. Though many inorganic feed additives have remarkably reduced methane emissions from ruminants, their usage as feed additives remains unappealing because of health and safety concerns. Hence, feed additives sourced from biological materials such as direct-fed microbials have emerged as a promising technique in mitigating enteric methane emissions.

• Animal Bioscience
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• 제37권2_spc호
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• pp.360-369
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• 2024

Ruminal methane production functions as the main sink for metabolic hydrogen generated through rumen fermentation and is recognized as a considerable source of greenhouse gas emissions. Methane production is a complex trait affected by dry matter intake, feed composition, rumen microbiota and their fermentation, lactation stage, host genetics, and environmental factors. Various mitigation approaches have been proposed. Because individual ruminants exhibit different methane conversion efficiencies, the microbial characteristics of low-methane-emitting animals can be essential for successful rumen manipulation and environment-friendly methane mitigation. Several bacterial species, including Sharpea, uncharacterized Succinivibrionaceae, and certain Prevotella phylotypes have been listed as key players in low-methane-emitting sheep and cows. The functional characteristics of the unclassified bacteria remain unclear, as they are yet to be cultured. Here, we review ruminal methane production and mitigation strategies, focusing on rumen fermentation and the functional role of rumen microbiota, and describe the phylogenetic and physiological characteristics of a novel Prevotella species recently isolated from low methane-emitting and high propionate-producing cows. This review may help to provide a better understanding of the ruminal digestion process and rumen function to identify holistic and environmentally friendly methane mitigation approaches for sustainable ruminant production.

• Asian-Australasian Journal of Animal Sciences
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• 제32권6호
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• pp.808-814
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• 2019

Objective: The objective of this study was to investigate the effects of essential oil mixture (EOM) supplementation on rumen fermentation characteristics and microbial changes in an in vitro. Methods: Three experimental treatments were used: control (CON, no additive), EOM 0.1 (supplementation of 1 g EOM/kg of substrate), and EOM 0.2 (supplementation of 2 g EOM/kg of substrate). An in vitro fermentation experiment was carried out using strained rumen fluid for 12 and 24 h incubation periods. At each time point, in vitro dry matter digestibility (IVDMD), neutral detergent fiber digestibility (IVNDFD), pH, ammonia nitrogen ($NH_3-N$), and volatile fatty acid (VFA) concentrations, and relative microbial diversity were estimated. Results: After 24 h incubation, treatments involving EOM supplementation led to significantly higher IVDMD (treatments and quadratic effect; p = 0.019 and 0.008) and IVNDFD (linear effect; p = 0.068) than did the CON treatment. The EOM 0.2 supplementation group had the highest $NH_3-N$ concentration (treatments; p = 0.032). Both EOM supplementations did not affect total VFA concentration and the proportion of individual VFAs; however, total VFA tended to increase in EOM supplementation groups, after 12 h incubation (linear; p = 0.071). Relative protozoa abundance significantly increased following EOM supplementation (treatments, p<0.001). Selenomonas ruminantium and Ruminococcus albus (treatments; p<0.001 and p = 0.005), abundance was higher in the EOM 0.1 treatment group than in CON. The abundance of Butyrivibrio fibrisolvens, fungi and Ruminococcus flavefaciens (treatments; p<0.001, p<0.001, and p = 0.005) was higher following EOM 0.2 treatment. Conclusion: The addition of newly developed EOM increased IVDMD, IVNDFD, and tended to increase total VFA indicating that it may be used as a feed additive to improve rumen fermentation by modulating rumen microbial communities. Further studies would be required to investigate the detailed metabolic mechanism underlying the effects of EOM supplementation.

• Asian-Australasian Journal of Animal Sciences
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• 제26권8호
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• pp.1144-1151
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• 2013

In this study, protein domains with cellulase activity in goat rumen microbes were investigated using metagenomic and bioinformatic analyses. After the complete genome of goat rumen microbes was obtained using a shotgun sequencing method, 217,892,109 pair reads were filtered, including only those with 70% identity, 100-bp matches, and thresholds below $E^{-10}$ using METAIDBA. These filtered contigs were assembled and annotated using blastN against the NCBI nucleotide database. As a result, a microbial community structure with 1431 species was analyzed, among which Prevotella ruminicola 23 bacteria and Butyrivibrio proteoclasticus B316 were the dominant groups. In parallel, 201 sequences related with cellulase activities (EC.3.2.1.4) were obtained through blast searches using the enzyme.dat file provided by the NCBI database. After translating the nucleotide sequence into a protein sequence using Interproscan, 28 protein domains with cellulase activity were identified using the HMMER package with threshold E values below $10^{-5}$. Cellulase activity protein domain profiling showed that the major protein domains such as lipase GDSL, cellulase, and Glyco hydro 10 were present in bacterial species with strong cellulase activities. Furthermore, correlation plots clearly displayed the strong positive correlation between some protein domain groups, which was indicative of microbial adaption in the goat rumen based on feeding habits. This is the first metagenomic analysis of cellulase activity protein domains using bioinformatics from the goat rumen.