• Asian-Australasian Journal of Animal Sciences
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• 제16권5호
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• pp.748-763
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• 2003

Anaerobic rumen microorganisms mainly bacteria, protozoa and fungi degrade ligno-cellulosic feeds consumed by the ruminants. The ruminants in developing countries are predominantly maintained on low grade roughage and grazing on degraded range land resulting in their poor nutrient utilization and productivity. Hence, manipulation of rumen fermentation was tried during last two decades to optimize ruminal fermentation for improving nutrient utilization and productivity of the animals. Modification of rumen microbial composition and their activity was attempted by using chemical additives those selectively effect rumen microbes, introduction of naturally occurring or genetically modified foreign microbes into the rumen and genetically manipulation of existing microbes in the rumen ecosystem. Accordingly, rumen protozoa were eliminated by defaunation for reducing ruminal methane production and increasing protein outflow in the intestine, resulting in improve growth and feed conversion efficiency of the animals. Further, Interspecies trans-inoculation of rumen microbes was also successfully used for annulment of dietary toxic factor. Additionally, probiotics of bacterial and yeast origin have been used in animal feeding to stabilize rumen fermentation, reduced incidence of diarrhoea and thus improving growth and feed conversion efficiency of young stalk. It is envisaged that genetic manipulation of rumen microorganisms has enormous research potential in developing countries. In view of feed resource availability more emphasis has to be given for manipulating rumen fermentation to increase cellulolytic activity for efficient utilization of low grade roughage.

• Asian-Australasian Journal of Animal Sciences
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• 제20권1호
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• pp.70-74
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• 2007

An in vitro study was carried out to investigate the differences in rumen microbes and fiber degradation capacity between sheep and goats. Three local male sheep and three Inner Mongolia male cashmere goats (aged 1.5 to 2 years; weight 25.0 to 32.0 kg) were each fitted with a permanent rumen cannula used to provide rumen fluid. Cycloheximide was used to eliminate rumen anaerobic fungi. The results showed that the quantities of fungal zoospores in the culture fluid of the control group were significantly greater in the sheep than in the goats; however, bacteria and protozoa counts were significantly higher in goats than in sheep. The digestibility of straw dry matter did not differ significantly between the two species before elimination of fungi, but tended to be higher for sheep (55.4%) than for goats (53.3%). The results also indicated that bacteria counts increased significantly after elimination of anaerobic fungi; however, the digestibility of straw dry matter significantly decreased by 12.1% and 8.6% for sheep and goats respectively. This indicated that the anaerobic fungi of the rumen played an important role in degradation of fiber.

• Animal Bioscience
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• 제37권2_spc호
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• pp.323-336
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• 2024

Molecular hydrogen (H₂) and formate (HCOO^-) are metabolic end products of many primary fermenters in the rumen ecosystem. Both play a vital role in fermentation where they are electron sinks for individual microbes in an anaerobic environment that lacks external electron acceptors. If H₂ and/or formate accumulate within the rumen, the ability of primary fermenters to regenerate electron carriers may be inhibited and microbial metabolism and growth disrupted. Consequently, H₂- and/or formate-consuming microbes such as methanogens and possibly homoacetogens play a key role in maintaining the metabolic efficiency of primary fermenters. There is increasing interest in identifying approaches to manipulate the rumen ecosystem for the benefit of the host and the environment. As H₂ and formate are important mediators of interspecies interactions, an understanding of their production and utilization could be a significant starting point for the development of successful interventions aimed at redirecting electron flow and reducing methane emissions. We conclude by discussing in brief ruminant methane mitigation approaches as a model to help understand the fate of H₂ and formate in the rumen ecosystem.

• Asian-Australasian Journal of Animal Sciences
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• 제12권6호
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• pp.988-1001
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• 1999

The rumen ecosystem is increasingly being recognized as a promising source of superior polysaccharide-degrading enzymes. They contain a wide array of novel enzymes at the levels of specific activities of 1,184, 1,069, 119, 390, 327 and $946{\mu}mol$ Reducing sugar release/min/mg protein for endoglucanase, xylanase, polygalactouronase, amylase, glucanase and arabinase, respectively. These enzymes are mainly located in the surface of rumen microbes. However, glycoside-degrading enzymes (e.g. glucosidase, fucosidase, xylosidase and arabinofuranosidase, etc.) are mainly located in the rumen fluid, when detected enzyme activities according to the ruminal compartments (e.g. enzymes in whole rumen contents, feed-associated enzymes, microbial cell-associated enzymes, and enzymes in the rumen fluid). Ruminal fungi are the primary contributors to high production of novel enzymes; the bacteria and protozoa also have important functions, but less central roles. The enzyme activities of bacteria, protozoa and fungi were detected 32.26, 19.21 and 47.60 mol glucose release/min/mL mediem for cellulose; 42.56, 14.96 and 64.93 mmol xylose release/min/mL medium after 48h incubation, respectively. The polysachharide-degrading enzyme activity of ruminal anaerobic fungi (e.g. Neocallimastix patriciarum and Piromyces communis, etc.) was much higher approximately 3~6 times than that of aerobic fungi (e.g. Tricoderma reesei, T. viridae and Aspergillus oryzae, etc.) used widely in industrial process. Therefore, the rumen ecosystem could be a growing source of novel enzymes having a tremendous potential for industrial applications.

• Asian-Australasian Journal of Animal Sciences
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• 제23권3호
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• pp.410-416
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• 2010

Methane emitted from ruminant livestock is regarded as a loss of feed energy and also a contributor to global warming. Methane is synthesized in the rumen as one of the hydrogen sink products that are unavoidable for efficient succession of anaerobic microbial fermentation. Various attempts have been made to reduce methane emission, mainly through rumen microbial manipulation, by the use of agents including chemicals, antibiotics and natural products such as oils, fatty acids and plant extracts. A newer approach is the development of vaccines against methanogenic bacteria. While ionophore antibiotics have been widely used due to their efficacy and affordable prices, the use of alternative natural materials is becoming more attractive due to health concerns regarding antibiotics. An important feature of a natural material that constitutes a possible alternative methane inhibitor is that the material does not reduce feed intake or digestibility but does enhance propionate that is the major hydrogen sink alternative to methane. Some implications of these approaches, as well as an introduction to antibiotic-alternative natural materials and novel approaches, are provided.

• Journal of Animal Science and Technology
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• 제48권5호
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• pp.709-718
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• 2006

식물유래 생리활성물질인 garlic, scallion, fla- vonoid, urushiol 및 anthocyanidin과 기존의 항균 제품인 Bio-MOS?瑛? 병원성 미생물과 반추위 미생물에 대한 효과를 조사하기 위하여 병원성 균인 Escherichia coli O157, Salmonella paratyphi, Listeria monocytogenes, Staphylococcus aureus에 항균활성과 in vitro 반추위 미생물 성장률, 가스 생성량, 암모니아 농도, CMCase 활성 및 미생물 수를 측정하였다. 생리활성물질 0.10% 첨가 후, 배양시험에서는 flavonoid, scallion 및 Bio-MOS?怜? 병원성 미생물의 성장을 억제하였으나, paper disc법에 의한 항균활성 시험에서는 flavonoid나 scallion을 5.00%이상 처리 시 clear zone이 뚜렷하였으며, scallion이 가장 강력한 항균활성을 가지고 있는 것으로 나타났다. 생리활성물질의 in vitro 반추위 미생물 발효에 대한 영향은 크지 않았는데, 병원균에 활성을 나타내었던 flavonoid는 1.00% 처리 시 CMCase의 활성이 완전히 없어져 반추위 미생물에 대한 억제효과가 있는 것으로 나타났다. 그러나 scallion은 병원균에는 강한 항균활성을 가지면서 반추위 미생물 발효에는 저해작용을 나타내지 않아 반추 가축의 대체 천연항균제로서 개발 가능성을 나타내었다.

• 생명과학회지
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• 제17권11호
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• pp.1555-1561
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• 2007

본 연구는 무기물성 및 식물성 유래 생리활성물질로서 scoria, germanium, charcoal, 생강, stevia 및 CLA(conjugated linoleic acid)가 병원성 미생물 및 반추위 미생물에 대한 작용을 조사하기 위하여 수행되었다. 병원성 균으로서 Escherichia coli O157, Salmonella paratyphi, Listeria monocytogenes 및 Staphylococcus aureus에 적용하여 항균활성을 측정하고, in vitro 발효 시 반추위 미생물 성장률, 가스 생성량, 암모니아 농도, CMCase 활성 및 미생물의 수를 측정하였다. 병원성 미생물 배양액에 생강을 0.1% 첨가한 구에서만 항균활성이 나타났으나, paper disc법에 의한 항균활성 시험에서는 stevia 10%첨가구와 CLA 10% 첨가구에서 E. coli에 대해서 항생제 첨가구인 positive control 구와 비슷한 크기의 clear zone을 형성하였다. in vitro 반추위 미생물 발효시험에서는 생강, stevia 및 CLA가 반추위 박테리아와 프로토조아의 증식을 억제하는 것으로 나타났는데, 특히 생강 첨가구의 경우 메탄 생성균의 서식지로 알려져 있는 프로토조아를 크게 억제함으로써 메탄생성 억제제로서 개발 가능성이 있는 것으로 사료된다.

• Asian-Australasian Journal of Animal Sciences
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• 제16권1호
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• pp.104-115
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• 2003

A series of experiments was carried out to determine the possibility for the non-ionic surfactant (NIS) as a feed additive for ruminant animals. The effect of the NIS on (1) the enzyme distribution in the rumen fluids of Hereford bulls, (2) the growth of pure culture of rumen bacteria and (3) rumen anaerobic fungi, (4) the ruminal fermentation characteristics of Korean native cattle (Hanwoo), and (5) the performances of Holstein dairy cows were investigated. When NIS was added to rumen fluid at the level of 0.05 and 0.1% (v/v), the total and specific activities of cell-free enzymes were significantly (p<0.01) increased, but those of cell-bound enzymes were slightly decreased, but not statistically significant. The growth rates of ruminal noncellulolytic species (Ruminobacter amylophilus, Megasphaera elsdenii, Prevotella ruminicola and Selenomonas ruminantium) were significantly (p<0.01) increased by the addition of NIS at both concentrations tested. However, the growth rate of ruminal cellulolytic bacteria (Fibrobacter succinogenes, Ruminococcus albus, Ruminococcus flavefaciens and Butyrivibrio fibrisolvens) were slightly increased or not affected by the NIS. In general, NIS appears to effect Gram-negative bacteria more than Gram-positive bacteria; and non-cellulolytic bacteria more than cellulolytic bacteria. The growth rates of ruminal monocentric fungi (Neocallimastix patriciarum and Piromyces communis) and polycentric fungi (Orpinomyces joyonii and Anaeromyces mucronatus) were also significantly (p<0.01) increased by the addition of NIS at all concentrations tested. When NIS was administrated to the rumen of Hanwoo, Total VFA and ammonia-N concentrations, the microbial cell growth rate, CMCase and xylanase activities in the rumen increased with statistical difference (p<0.01), but NIS administration did not affect at the time of 0 and 9 h post-feeding. Addition of NIS to TMR resulted in increased TMR intake and increased milk production by Holstein cows and decreased body condition scores. The NEFA and corticoid concentrations in the blood were lowered by the addition of NIS. These results indicated that the addition of NIS may greatly stimulate the release of some kinds of enzymes from microbial cells, and stimulate the growth rates of a range of anaerobic ruminal microorganisms, and also stimulate the rumen fermentation characteristics and animal performances. Our data indicates potential uses of the NIS as a feed additive for ruminant animals.

• Asian-Australasian Journal of Animal Sciences
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• 제28권4호
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• pp.530-537
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• 2015

The objective of this study was to evaluate the in vitro effects of flavonoid-rich plant extracts (PE) on ruminal fermentation characteristics and methane emission by studying their effectiveness for methanogenesis in the rumen. A fistulated Holstein cow was used as a donor of rumen fluid. The PE (Punica granatum, Betula schmidtii, Ginkgo biloba, Camellia japonica, and Cudrania tricuspidata) known to have high concentrations of flavonoid were added to an in vitro fermentation incubated with rumen fluid. Total gas production and microbial growth with all PE was higher than that of the control at 24 h incubation, while the methane emission was significantly lower (p<0.05) than that of the control. The decrease in methane accumulation relative to the control was 47.6%, 39.6%, 46.7%, 47.9%, and 48.8% for Punica, Betula, Ginkgo, Camellia, and Cudrania treatments, respectively. Ciliate populations were reduced by more than 60% in flavonoid-rich PE treatments. The Fibrobacter succinogenes diversity in all added flavonoid-rich PE was shown to increase, while the Ruminoccocus albus and R. flavefaciens populations in all PE decreased as compared with the control. In particular, the F. succinogenes community with the addition of Birch extract increased to a greater extent than that of others. In conclusion, the results of this study showed that flavonoid-rich PE decreased ruminal methane emission without adversely affecting ruminal fermentation characteristics in vitro in 24 h incubation time, suggesting that the flavonoid-rich PE have potential possibility as bio-active regulator for ruminants.

• 생명과학회지
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• 제28권10호
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• pp.1244-1253
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• 2018

반추위 속에는 박테리아, 고세균, 프로토조아, 곰팡이 및 바이러스와 같은 다양한 미생물들이 편성의 혐기조건에서 공생하고 있다. 사료의 발효에 중요한 역할을 하고 있는 반추위 미생물은 위내 발효과정에서 에너지 손실에 영향을 주는 메탄의 발생을 제외하면 에너지와 단백질 대사에 필수적인 다양한 휘발성 지방산을 생산한다. 반추위내 미생물의 이용효율을 개선시키기 위해 사료배합비조절, 천연사료첨가제, 생균제첨가 등의 다양한 접근방법들이 사용되고 있다. 최근에 반추위 군집에 대한 메타유전체 또는 메타전사체와 같은 차세대 유전체 해독기술 또는 차세대 시퀀싱 기술의 적용으로 반추위 미생물의 다양성 및 기능에 대한 이해가 크게 증가하였다. 특히 메타단백질체와 메타대사체는 반추위 생태계의 복잡한 미생물네트워크에 대한 더 깊은 통찰력을 제공할 뿐만 아니라, 다양한 반추가축용 사료에 대한 반응을 제공함으로서 생산효율을 개선시키는데 기여하였다. 본 논문에서는 반추위내 사료의 발효와 이용을 향상시키기 위한 메타오믹스 기술, 즉, 메타유전체, 메타전사체, 메타단백질체 및 메타대사체의 최신 응용기술을 요약하고자 한다.