항균제와 항마이코플라스마제는 가축과 가금의 질병을 예방하고 관리하는 데 가장 많이 쓰이는 치료제입니다. 종류가 다양하고 작용 기전과 용도, 부작용도 각기 다르기 때문에, 이 가이드에서는 수의학적 관점에서 이들의 분류와 특징, 주의사항을 정리하여 올바르고 안전한 사용에 도움이 되고자 합니다.
분류 및 항균제의 작용 기전
작용 방식에 따라 항균제는 크게 네 가지 유형으로 나뉩니다:
- 살균성 약물(제I형): 페니실린과 세팔로스포린처럼 세균의 세포벽 형성을 차단하여 증식이 빠른 세균에 의한 감염에 효과가 뛰어납니다.
- 정지기 살균 약물(제II형): 아미노글리코사이드와 폴리믹신처럼 세균의 세포막이나 단백질 생성을 방해하여 정지기의 세균을 표적으로 합니다.
- 속효성 정균 약물(제III형) 테트라사이클린, 클로람페니콜, 마크롤라이드 등이 포함됩니다. 세균의 단백질 생성을 빠르게 억제하며, 고용량에서는 세균을 사멸시킬 수 있습니다.
- 지효성 정균 약물(제IV형): 설폰아미드처럼 세균의 대사를 느리게 만들어 작용 발현이 더딥니다.
약물 병용의 효과
- 제I형 + 제II형: 함께 사용하면 효과가 더 좋아집니다
- 제I형 + 제III형: 서로 효과를 상쇄할 수 있습니다
- 제II형 + 제III형: 함께 사용하면 효과가 더 좋아지거나 상가적으로 작용합니다
- 제I형 + 제IV형: 함께 사용하면 효과가 더 좋아집니다
항균제의 주요 종류와 용도
다음은 축산 및 가금 농가에서 흔히 사용되는 항균제로, 작용 기전과 치료 대상, 주의사항을 자세히 정리했습니다:
β-락탐계
작용 기전: 세균의 세포벽 형성을 차단하고 세균을 분해하는 효소를 유발하는 β-락탐 고리를 함유하고 있습니다.
세부 유형: 페니실린, 세팔로스포린, 비전형적 β-락탐, β-락타마제 억제제.
적용 대상: 그람양성균(G+), 그람음성균(G-), 일부 혐기성 세균에 효과적입니다.
용도: Widely used for respiratory, digestive, and soft tissue infections due to decisive action and low side effects, like swine streptococcal disease and avian colibacillosis (E. coli infections in poultry).
Precautions: Be cautious with animals allergic to penicillins; don’t mix with fast-acting bacteria-suppressing drugs to avoid weakening their effect.
아미노글리코사이드계
작용 기전: Target the 30S ribosomal subunit to block protein production and damage cell membranes; these are dose-dependent bacteria-killers.
Common Drugs: Streptomycin, gentamicin, amikacin, and others.
What They Target: They work against aerobic G-bacilli (e.g., E. coli, Salmonella) and some G+ bacteria (e.g., Staphylococcus); they do not affect anaerobes.
용도: Treat serious G- infections in pigs and poultry, like piglet yellow and white diarrhea and avian septicemia.
Precautions: Risk of ear and kidney damage; monitor kidney function and avoid long-term use.
마크롤라이드계
작용 기전: Target the 50S ribosomal subunit to stop protein production; usually fast-acting bacteria-suppressors but can kill at high doses.
Common Drugs:
First generation: Erythromycin, tylosin (less commonly used).
Second generation: Roxithromycin, clarithromycin, azithromycin.
Third generation: Telithromycin, quinupristin (less resistance).
First generation: Erythromycin, tylosin (less commonly used).
Second generation: Roxithromycin, clarithromycin, azithromycin.
Third generation: Telithromycin, quinupristin (less resistance).
What They Target: Effective against G+ bacteria, some G- bacteria, and atypical pathogens (e.g., Mycoplasma, Chlamydia).
Uses: Treat swine mycoplasma pneumonia and avian chronic respiratory disease (CRD).
주의사항: Resistance is increasing; choose drugs based on susceptibility tests.
테트라사이클린계
작용 기전: Target the 30S ribosomal subunit to block protein production.
Common Drugs: Tetracycline, doxycycline, minocycline.
What They Target: Broad-spectrum, effective against G+, G- bacteria, and Mycoplasma.
용도: Treat avian cholera, swine respiratory disease, and bovine pasteurellosis.
Precautions: Resistance is common; don’t use dairy products (reduces absorption).
플루오로퀴놀론계
작용 기전: Block bacterial DNA enzymes, stopping DNA replication.
Common Drugs: Enrofloxacin, ciprofloxacin, levofloxacin.
What They Target: Effective against G+ cocci, G- bacteria, Mycoplasma, and anaerobes.
용도: Treat avian colibacillosis (E. coli infections in poultry) and swine respiratory infections.
Precautions: Use cautiously in young animals; may affect cartilage growth.
글리실사이클린계
Representative Drug: Tigecycline.
작용 기전: Like tetracyclines, they block protein production.
What They Target: Effective against multidrug-resistant bacteria (e.g., MRSA, enterococci) and anaerobes.
용도: Treat complex skin, soft tissue, and abdominal infections.
Precautions: Don’t use alone; save as a last-resort drug to limit resistance.
글리코펩타이드계
Common Drugs: Vancomycin, teicoplanin.
작용 기전: Block cell wall formation; effective against G+ bacteria.
용도: Treat resistant G+ infections, like MRSA-related swine skin infections.
Precautions: Monitor kidney function and hearing; don’t use for more than 14 days.
니트로이미다졸계
Common Drugs: Metronidazole, tinidazole.
작용 기전: Damage bacterial DNA; broad-spectrum antibacterial action.
What They Target: Effective against anaerobes, spirochetes, and Mycoplasma.
용도: Treat swine intestinal anaerobic infections and avian necrotic enteritis.
Precautions: Avoid alcohol during treatment to prevent severe reactions similar to those from mixing alcohol with certain drugs.
항균제 사용 시 주의사항
- Choose Wisely: Pick the right drug based on the type of bacteria, susceptibility tests, and animal species.
- Combination Therapy: Check how drugs work together or against each other to avoid combinations that don’t work.
- Dosage and Duration: Stick to recommended doses and treatment lengths to prevent resistance from overuse or underuse.
- Withdrawal Period: Follow withdrawal period rules (time before animals can be used for food) to avoid drug residues in food.
- Preventing Resistance: Rotate drug types regularly to reduce resistant bacteria.
결론
Antibacterial and anti-mycoplasma drugs are vital for preventing and treating diseases in livestock and poultry, but they should be used carefully and based on science. Veterinarians should pick the best drug plan by examining clinical signs, lab tests, and drug properties to boost treatment success, lower resistance risks, and protect animal and public health.
