Abstract
This study was carried out to evaluate the effect of replacing antibiotics by organic acid mixture on growth performances and blood metabolites in growing pigs. Twenty-five crossbred pigs (Large White${\times}$Landrace) at the age of 79 days were fed five different diets by supplementing organic acid mixture and chlortetracycline. The experimental diets were consisted of diets without antibiotics supplementation (control), diets added 100mg/kg of chlortetracycline to control diet (T1), diets added 100mg/kg of chlortetracycline and 0.1% of $Acidomix^{(R)}$ (comprising formic acid 25%, sorbic acid 10%, fumaric acid 10%) to control diet (T2), diets added 0.1% of $Acidomix^{(R)}$ to control diet (T3), and diets added 0.3% of $Acidomix^{(R)}$ to control diet (T4). The changes in feed conversion ratio, average daily gain and blood metabolites were investigated. Twenty-five pigs were allotted to five treatments with five replications of each and the experiment was conducted on the basis of complete randomized design for 6 weeks. Average daily gain was significantly (p<0.05) different between T4 and control diets. All treatments including diets added $Acidomix^{(R)}$ and chlortetracycline were slightly higher than control diets. The feed intakes did not show a significant difference between the control and other treatments, and did not give change in feed intake by the addition of $Acidomix^{(R)}$. No differences on feed conversion ratio among treatments were observed but T4 and T3 treatments showed lower value than other treatments. The concentrations of blood urea nitrogen, total cholesterol and triglyceride were significantly (p<0.05) different among treatments, but their values were within the normal range representing that effects on blood profile by organic acid or antibiotics supplementation were not found. The results from this study indicated that adding chlortetracycline or organic acid mixtures to diets showed tendency to improve average daily gain and feed conversion ratio in growing pigs. These results showed that antibiotics could be replaced by organic acid mixture in growing pig diets, leading to stimulated growth and improved feed conversion ratio.
본 시험은 돼지사료에 첨가하여 사용하던 항생제를 대체하기 위한 유기산제의 효과를 평가하기 위하여 생후 79일령, $32{\sim}33kg$ 범위의 일대 잡종(Large White${\times}$Landrace) 돼지 25두에 항생제 무첨가사료(대조구)와 대조구 사료에 각각 Chlortetracycline(CTC) 100mg/kg을 첨가한 사료(T1), CTC 100mg/kg과 $Acidomix^{(R)}$ (formic acid 25%, sorbic acid 10%, fumaric acid 10%)를 0.1% 첨가한 사료(T2), $Acidomix^{(R)}$를 0.1% 첨가한 사료(T3), $Acidomix^{(R)}$를 0.3% 첨가한 사료(T4)의 5개 처리로 구분하여 급여한 다음 생산성과 혈액성상의 변화를 조사하였다. 시험 기간 동안 육성전기 돼지의 일당증체량은 생육이 진행됨에 따라 지속적으로 증가하였고 평균 일당증체 량은 T4구 > T2구 > T1구> T3구 > 대조구 순으로 낮아졌다. 특히 T4구가 대조구에 비하여 유의하게 높았고(p<0.05) 다음으로 CTC 또는 $Acidomix^{(R)}$를 첨가한 모든 처리구가 대조구에 비하여 높았다. 사료요구율의 경우에도 생육이 진행됨에 따라 높아졌고 평군 사료요구 율은 T4구 < T3구 < T2구 < T1구 < 대조구의 순서로 높아져 T4구와 T3구의 사료요구율이 낮았으나 통계적으로 유의한 차이는 나타내지 않았다. 사료 섭취량은 대조구 및 처리구 간에서 큰 차이를 보이지 않았다. 혈액내의 요소태 질소(BUN), cholesterol, triglyceride, total lipid함량은 유의한 차이가 인정되었으나 비교적 정상 수치에 근접한 결과로 개체간의 차이로 판단되며 유기산 또는 항생제의 급여가 혈액성상에는 그다지 큰 영향을 미치지 않았다. 이상의 결과를 볼 때, 유기산제의 첨가가 대조구 혹은 항생제 첨가구 보다 육성전기 돼지에 있어서 일당증체량을 증가시키고 사료요구율은 낮아져 유기산제에 의한 돼지의 성장촉진 및 사료요구율의 개선효과가 나타남으로써 항생제의 대체 가능성을 시사하였다.