한국 토종닭의 암수 분리사육과 혼합사육에 따른 스트레스 반응과 생산능력 비교 = Comparison of Stress Response and Production Performance between Separate and Mixed rearing of Male and Female Korean Native Chicken

국문 초록 (Abstract)

닭은 사육 기간동안 많은 외부적 환경 스트레스에 노출되어 있으며, 사육 밀도 및 사육 형태에 따른 스트레스 반응 정도가 매우 다르다. 최근 가축 복지 및 친환경 사육 방식이 요구되면서 사육 형태에 있어 암수 혼합사육이 증가되고 있는 추세이나 암수 분리사육과 혼합사육 간의 스트레스 반응과 생산성에 미치는 영향에 대해서는 거의 알려진 바가 없다. 따라서 본 연구에서는 한국 토종닭을 이용하여 암수 분리사육과 혼합사육에 따른 스트레스 반응과 생산능력을 비교 분석하고자 하였다.
스트레스 반응 정도를 분석하기 위하여 혼합사육 이전인 37주령 때와 혼합사육 후 2주가 경과한 39주령 때 케이지별 무작위로 암수 85수를 선정하고 동일 개체로부터 혈액을 채취하여 H/L ratio, HSP 및 세포 내 DNA 손상율을 분석하였다. H/L ratio는 혼합사육하였을 경우 분리사육을 할 때보다 3배 정도 유의하게 상승한 것으로 나타났다(P<0.01). 동일한 환경에서 암수 간의 차이는 없는 것으로 나타났다. HSPs(Heat shock protein)중 HSP-70, HSP-90α 및 HSP-90β의 발현율을 확인한 결과 모든 HSPs의 유전자 발현율이 암수 혼합사육 이전에 비해 혼합사육 이후 2.5∼3.4배 정도 유의하게 상승한 것으로 나타났다(P<0.01). 특히 암컷이 수컷에 비해 혼합사육에 따른 HSPs 발현율 증가가 컸으며, 동일 환경에서 암수 간의 차이는 없는 것으로 나타났다. 세포 내 DNA 손상율은 혼합사육하였을 경우 분리사육을 할 때보다 손상율이 높은 양상을 나타내었으며(P<0.01), 동일한 환경에서 암수 간의 차이는 없는 것으로 나타났다.
암수 혼합사육과 분리사육간 산육능력의 비교에서 두 처리구 간 30주령 및 40주령 체중과 동기간의 증체량에서 차이를 보이지 않았다. 36주령부터 43주령까지의 생존율에서도 두 처리구 간의 차이는 없는 것으로 나타났다. 36주령부터 43주령까지의 산란능력 분석 결과, 암수 분리사육 한 개체들이 혼합사육한 개체들에 비해 일계 산란율과 산란 지수가 높았고 난중은 차이가 없는 것으로 나타났다.
이상의 결과들을 종합하면, 한국 토종닭에 있어 암수 혼합사육이 암컷과 수컷 모두에게 매우 큰 스트레스 요인으로 작용하는 것으로 판단된다. 암수 혼합사육과 분리사육간 산육능력 및 생존율의 차이는 없는 것을 보이나, 암수 혼합사육이 분리사육에 비해 산란능력의 저하를 초래할 수 있는 것으로 보인다.

목차 (Table of Contents)

• Ⅰ. 서론 ············································································· 1
• Ⅱ. 연구사 ········································································· 3
• 1. 사육형태 ······································································· 3
• 2. 암수 분리 및 혼합사육과 스트레스 관련 연구 ············································ 5
• 3. 암수 분리 및 혼합사육과 생산능력 관련 연구 ············································ 7
• Ⅲ. 한국 토종닭의 암수 혼합사육에 의한 스트레스 반응 ···························· 9
• 1. 서론 ································································································ 9
• 2. 재료 및 방법 ·················································································· 10
• 1) 공시동물 및 사육 방법 ··································································· 10
• 2) Heat Shock Proteins 유전자 발현율 분석 ·········································· 10
• 3) Heterophil : Lymphocyte의 비율 분석 ················································ 13
• 4) 세포 내 DNA 손상율 분석 ··························································· 13
• 5) 통계분석 ················································································· 13
• 3. 결과 및 고찰 ··············································································· 14
• 1) Heat Shock Proteins 유전자 발현율 분석 ··········································· 14
• 2) Heterophil : Lymphocyte의 비율 분석 ················································ 16
• 3) 세포 내 DNA 손상율 분석 ····························································· 19
• Ⅳ. 한국 토종닭의 암수 분리사육과 혼합사육이 생산능력에 미치는 영향 ·········· 22
• 1. 서론 ························································································ 22
• 2. 재료 및 방법 ············································································· 23
• 1) 공시동물 및 사육 방법 ·································································· 23
• 2) 생산능력 조사 항목 ···································································· 23
• 3) 통계분석 ················································································· 23
• 3. 결과 및 고찰 ··············································································· 24
• 1) 산육능력 ··················································································· 24
• 2) 생존율 ······················································································ 27
• 2) 산란능력 ····················································································· 29
• Ⅴ. 결 론 ················································································ 32
• Ⅵ. 참고문헌 ·················································································· 34
• Ⅶ. 국문초록 ············································································· 45
• Ⅷ. Abstract ·········································································· 47