• 한국환경농학회지
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• 제29권3호
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• pp.273-281
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• 2010

본 연구는 강원도 원주 지역의 계분 퇴비화 시설 인근의 농경지 토양, 지표수 및 저질토에 대한 TCs계열 3종(TC, CTC 및 OTC), SAs 계열 3종(SMX, STZ 및 SMT), IPs 계열 3종(LSL, MNS 및 SLM) 및 MLs 계열 1종(TYL) 등 총 4개 계열 10종의 항생물질을 선정하여 영농시기 별 잔류특성을 조사하였다. 토양 시료의 경우 TCs가 다른 계열 항생물질과 비교하여 가장 높은 농도로 검출되었으며 이는 TCs 내 케톤기와 토양 내 2가 양이온이 복합체를 형성, 표토에 강하게 흡착되어 심토까지 이동하지 않고 축적된 것으로 추측된다. 반면 TCs와 비교해 토양 내 SAs 잔류량이 낮은 이유는 적은 사용량과 낮은 흡착계수에서 기인된 것으로 판단되었다. 수질시료의 TCs는 집중강우로 인한 토양유실 및 이후 유량 감소로 인해 6월보다 9월에 높은 농도를 보였다. 저질토 내 TCs 농도 증가 이유가 양이온간의 복합체 형성, 이온교환 및 부식산의 수소결합으로 인해 지표수로 유입된 TCs가 저질토로 흡착, 축적되었기 때문으로 판단된다. 본 연구를 통해 계분퇴비 시용시 주변환경으로 높은 농도의 항생물질이 유입될 가능성이 있으며, 이로 인해 토양 내 내성 박테리아 생성 및 생태계 교란뿐만 아니라 직 간접적으로 인간에게 피해가 우려되는 바 지속적인 모니터링을 통한 관리방안 마련이 필요할 것으로 판단된다.

• Asian-Australasian Journal of Animal Sciences
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• 제24권2호
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• pp.285-294
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• 2011

The abatement of methane emission from ruminants is an important global issue due to its contribution to greenhouse gas with carbon dioxide. Methane is generated in the rumen by methanogens (archaea) that utilize metabolic hydrogen ($H_2$) to reduce carbon dioxide, and is a significant electron sink in the rumen ecosystem. Therefore, the competition for hydrogen used for methanogenesis with alternative reductions of rumen microbes should be an effective option to reduce rumen methanogenesis. Some methanogens parasitically survive on the surface of ciliate protozoa, so that defaunation or decrease in protozoa number might contribute to abate methanogenesis. The most important issue for mitigation of rumen methanogenesis with manipulators is to secure safety for animals and their products and the environment. In this respect, prophylactic effects of probiotics, prebiotics and miscellaneous compounds to mitigate rumen methanogenesis have been developed instead of antibiotics, ionophores such as monensin, and lasalocid in Japan. Nitrate suppresses rumen methanogenesis by its reducing reaction in the rumen. However, excess intake of nitrate causes intoxication due to nitrite accumulation, which induces methemoglobinemia. The nitrite accumulation is attributed to a relatively higher rate of nitrate reduction to nitrite than nitrite to ammonia via nitroxyl and hydroxylamine. The in vitro and in vivo trials have been conducted to clarify the prophylactic effects of L-cysteine, some strains of lactic acid bacteria and yeast and/or ${\beta}$1-4 galactooligosaccharide on nitrate-nitrite intoxication and methanogenesis. The administration of nitrate with ${\beta}$1-4 galacto-oligosaccharide, Candida kefyr, and Lactococcus lactis subsp. lactis were suggested to possibly control rumen methanogenesis and prevent nitrite formation in the rumen. For prebiotics, nisin which is a bacteriocin produced by Lactococcus lactis subsp. lactis has been demonstrated to abate rumen methanogenesis in the same manner as monensin. A protein resistant anti-microbe (PRA) has been isolated from Lactobacillus plantarum as a manipulator to mitigate rumen methanogenesis. Recently, hydrogen peroxide was identified as a part of the manipulating effect of PRA on rumen methanogenesis. The suppressing effects of secondary metabolites from plants such as saponin and tannin on rumen methanogenesis have been examined. Especially, yucca schidigera extract, sarsaponin (steroidal glycosides), can suppress rumen methanogenesis thereby improving protein utilization efficiency. The cashew nutshell liquid (CNSL), or cashew shell oil, which is a natural resin found in the honeycomb structure of the cashew nutshell has been found to mitigate rumen methanogenesis. In an attempt to seek manipulators in the section on methane belching from ruminants, the arrangement of an inventory of mitigation technologies available for the Clean Development Mechanism (CDM) and Joint Implementation (JI) in the Kyoto mechanism has been advancing to target ruminant livestock in Asian and Pacific regions.