시료내 라이신 : 에너지 비율이 이유 자돈의 성장 및 영양소 소화율에 미치는 영향 DE RATIO ON THE GROWTH PERFORMANCE AND NUTRIENT DIGESTIBILITY IN WEANED PIGS = EFFECTS OF LYSINE

국문 초록 (Abstract)

본 연구는 현대의 빠르게 성장하는 이유자돈에서 사료내 Lys : DE 비율이 이유자돈의 성장 및 영양소 소화율에 미치는 영향을 알아보기 위하여 실시되었다. 평균체중 5.70±0.14의 이유자돈 (Yorkshire×Landrace×Duroc) 100두를 공시하였고, 제 1기 (0∼14일) 동안, 두 수준의 에너지 (3,400과 3,600 ㎉ DE/㎏)와 두 수준의 Lys : DE 비율 (4.4와 4.9 g/Mcal), 제 2기 (15∼28일) 동안, 두 수준의 에너지 (3,300과 3,500 ㎉ DE/㎏)와 두 수준의 Lys : DE 비율 (4.4와 4.9 g/Mcal)이 되도록, 2×2 요인법으로 설계하였으며 4처리 5반복 반복당 5두의 이유자돈이 공시되었다. 시험 전기간 (0∼28일)동안, 일당중체량 (ADG)은 저 에너지-고 Lys : DE구가 저 에너지-저 Lys : DE구 보다 높았으며, 사료요구율 (FCR)은 고 에너지-고 Lys : DE구가 저 에너지-고 Lys : DE구를 제외한 나머지 처리구들 보다 낮은 경향을 보여 주었으나 유의한 수준은 아니였다. 사료내 Lys : DE 비율이 높아짐에 따라 ADG가 높아지는 경향을 보여 주었으나 유의하지는 않았다 (P>0.05). 그러나 FCR은 Lys : DE 비율이 높아짐에 따라 유의하게 개선되었으며 (P<0.05). 에너지 수준에 따른 차이는 관찰되지 않았다. 제 1기 동안 영양소 소화율은 사료내 에너지수준에 따라 영향받지 않았다. 건물소화율과 총에너지 소화율은 Lys : DE 비율이 증가함에 따라 유의하게 개선되었다 (P<005). 제 2기 동안 조지방을 제외한 영양소 소화율은 사료내 에너지 수준간에 따라 영향받지 않았다. 사료내 Lys : DE 비율에 따른 영양소 소화율에 있어 유의한 차이는 관찰되지 않았다. 제 1기 동안 필수 및 비필수 아미노산 소화율에 있어서는, 처리에 따른 유의한 차이가 관찰되지 않았다. 그러나 제 2기 동안 총필수 아미노산과 총 아미노산 소화율이 사료내 Lys : DE 비율이 증가함에 따라 유의하게 개선되었다 (P<0.05). 본 실험결과는 이유자돈이 4.4 g Iysine/Mcal DE 수준보다 4.9 g Iysine/Mcal DE 수준의 사료를 효과적으로 이용할 수 있음을 제시해 주었다.

다국어 초록 (Multilingual Abstract)

This study was carried out to evaluate the effect of lysine:energy ratio (Lys : DE) on growth performance and nutrient digestibility of weaned pigs. A total of 100 pigs (Yorkshire × Landrace × Duroc) averaging 5.7±0.14 ㎏ of initial body weight were employed. Two levels of dietary energy (3,400 and 3,600 ㎉ DE/㎏) with two levels of Lys : DE ratio (4.4 and 4.9 g/Mcal) for phase I period (0 to 14 d) and two levels of energy (3,300 and 3,500 ㎉ DE/㎏) with two levels of Lys : DE ratio (4.4 and 4.9 g/Mca1) for phase II period (15 to 28 d) were involved in a two × two factorial arrangement, respectively. Each treatment had five replicates with five pigs per replicate. During phase I period (0 to 14 d), no difference between groups in ADFI, and feed conversion rate (FCR) was significant. However, FCR was significantly improved with increased Lys : DE ratio (P<0.05). During phase II period (15 to 28 d), ADG, ADFI and FCR were not significantly (P<0.05) different among groups. There was no interaction between dietary energy concentration and Lys : DE ratio in growth performances of weaned pigs. FCR, however, was improved with increased energy level and Lys : DE ratio (P<0.05). During the overall period (0 to 28 d), there was no interaction between dietary energy concentration and Lys : DE ratio in growth performances of weaned pigs. However, there was a tendency for higher ADG with higher Lys : DE ratio. FCR was significantly improved with increased Lys : DE ratio (P<0.05), but was not affected by dietary energy concentration.
During phase I period (0 to 14 d), no differences in nutrients digestibilities were observed between dietary energy levels. Between dietary Lys : DE ratios, dry matter (DM) and gross energy (GE) digestibilities were significantly (P<0.05) improved with higher Lys : DE ratio. During phase II period (15 to 28 d), no differences in nutrients digestibilities except energy levels. Between dietary Lys : DE ratios, no significant differences in nutrients digestibilities was observed. In regard to amino acids digestibilities, during phase I period (0 to 14 d), average values of essential amino acids (EAA), non-essential amino acids (NEAA) and total amino acids digestibilities were not significantly influenced by dietary energy levels and Lys : DE ratios. During phase II period ( 15 to 28 d), pigs fed high Lys : DE ratio diets showed significantly (P<0.05) higher total EAA and total amino acids digestibilities. The digestibilities of threonine, methionine, phenylalnine and serine were significantly improved as the dietary Lys : DE ratio increased.
In conclusion, the results of the current experiment indicate that fast-growing weaned pigs might be able to use more effectively diets contatining 4.9 g lysine/Mcal DE compared to diets containing 4.4 g lysine/Mcal DE.