저수준의 Lysine 사료에서 L-leucine 첨가수준이 비육후기 Duroc 품종 돼지의 성장 및 육질특성에 미치는 영향

Abstract

본 연구에서는 비육후기 Duroc 품종 돼지를 대상으로 저수준의 lysine 사료에 합성 L-leucine 첨가수준이 생산성, 도체 및 육질 특성에 미치는 영향을 평가하였다. 시험동물은 평균 74±1kg의 Duroc 품종 54두를 각 처리 당 6반복, 반복 당 3두씩 공시하였다. 시험사료는 lysine 0.45%의 기초사료에 합성 L-leucine을 각각 0% (CON), 1.5% (LEU 1.5) 및 3.0% (LEU 3.0) 첨가한 후 30일간 급여하였다.일당증체량, 사료섭취량 및 사료요구율은 처리구간에 유의적인 차이를 보이지 않았다. 도체특성에 있어서는 도체율 및 등지방두께는 처리구 간 유의적인 차이를 보이지 않았으나, 등심단면적은 L-leucine의 첨가수준이 높아짐에 따라 증가하는 경향을 나타내었다. 근내지방도는 L-leucine 첨가구가 대조구에 비하여 유의적으로 높았다(P<0.05). 육질 특성에서 조지방 함량이 유의적인 차이는 없었지만 L-leucine 첨가에 따라 증가하는 경향을 나타내었으며, CIE L*는 유의적으로 증가하였다(P<0.05). The objective of this study was to investigate effects of supplementation levels of L-leucine in low-lysine diets on growth performance and meat quality parameters in finishing Duroc pigs. A total of fifty-four pigs with an average initial weight of 74±1kg were allotted to one of three dietary treatments. Each treatment had six replications of three pigs per replicate. The treatment diets included 1)a corn-soybean meal basal diet containing lysine as low as 0.45% (CON), 2) basal diet plus 1.5% L-leucine (LEU 1.5), and 3) basal diet plus 3.0% L-leucine (LEU 3.0). No difference was found in ADG, ADFI and Feed/Gain among treatments. In carcass parameters, dressing precent and back-fat thickness were not affected by L-leucine levels, however, longissimus dorsi area tended to increase by supplementation of L-leucine. Marbling score was significantly higher (P<0.05) in LEU 1.5 and LEU 3.0 than in CON. In meat quality parameters, CIE L* of meat color significantly increased (P<0.05) and crude fat tended to increase by supplementation of L-leucine. However, there was no difference in water holding capacity, cooking loss and shear force value. This study suggests that dietary supplementation of L-leucine in low-lysine diets at the end of finishing period can produce high marbled pork which is preferred by Korean consumers.