earticle

영어

This study was conducted to determine the effects of dietary protein level and supplementation of protease on growth performance, nutrient digestibility, gut microflora, intestinal morphology and fecal noxious gas emission in weanling pigs. A total of 240 weaned pigs (Landrace×Yorkshire×Duroc, 5.82±0.3 kg) were used during 4 weeks in 2 phases (days 0-14, phase 1; and days 15-28, phase 2) feeding program based on age and initial body weight. Pigs were allocated to 2×2 factorial arrangement, including 2 protein levels (HP, high protein; LP, low protein) and 2 protease levels (with or without protease). The average daily gain in the LP treatment (357 g/d) was increased rather than the HP treatment (339 g/d). A greater avarage daily gain was observed in dietary suppiemented protease treatment (358 vs 339 g/d). Average feed intake was greater in the LP treatment (544 g/d) rather than the HP treatment (530 g/d). A greater average daily feed intake was observed in dietary supplemented protease treatment (552 vs 523 g/d). Dry matter and crude protein digestibility were increased in dietary supplemented protease treatment (82.62% and 76.08%, respectively) rather than non-supplemented treatment (81.74% and 75.13%, respectively). Ileal Lactobacillus spp. count increased in dietary supplemented protease treatment (7.42 vs 7.32 log10CFU/g). Emission of H2S was decreased in the LP treatment (4.41 ppm) rather than HP treatment (4.78 ppm). Emission of NH3 was decreased in dietary supplemented protease treatment (10.43 ppm vs 11.76 ppm). In conclusion, the decrease of dietary protein level and supplementation of protease had beneficial effects on growth performance, nutrient digestibility, gut microflora, and noxious gas emission in weanling pigs.

한국어

본 연구는 사료 내 단백질 수준 및 protease 첨가가 이 유자돈의 사양성적, 영양소 소화율, 장 내 미생물, 소장 형 태학적 변화 및 분 중 유해가스 발생에 미치는 영향을 알 아보기 위해 실시되었다. 총 240두의 이유자돈 (Landrace×Yorkshire×Duroc, 5.82±0.3kg)을 공시였으며, 4 주 간 2단계(days 0-14, phase 1; and days 15-28, phase 2) 로 나누어 사양실험을 진행하였다. 처리구는 사료 내 단백 질 두 수준과(phase 1, HP: CP 21% / LP: CP 19%; phase 2, HP: CP 19% / LP: CP 17%) protease 첨가 유무에 따 른 2×2 요인설계법에 준하였다. 연구 결과, 일당증체량은 LP 처리구(357g/d)가 HP처리구(339g/d)에 비하여 증가하 였고(p<0.05), 사료 내 protease 첨가한 처리구(358g/d)가 비첨가구(339g/d)에 비하여 증가하였다(p<0.05). 일당사료 섭취량은 LP 처리구(554g/d)가 HP(530g/d) 처리구에 비 하여 증가하였고(p<0.05), 사료 내 protease 첨가한 처리구 (552g/d)가 비첨가구(523g/d)에 비하여 증가하였다 (p<0.05). 사료 내 protease 첨가구의 건물소화율과 조단백 질 소화율(각각 82.62%, 76.08%)이 비첨가구(각각 81.74%, 75.13%)에 비해 증가되었고(p<0.05), 사료 내 protease 첨 가구의 Ileum Lactobacillus spp. 수치(7.42log10CFU/g)가 비 첨가구(7.32log10CFU/g)에 비하여 증가되었다(p<0.05). 또 한 LP 처리구의 암모니아 발생량(4.41ppm)이 HP처리구(4.78ppm)에 비하여 감소하였고(p<0.05), 사료 내 protease 첨가한 처리구의 황화수소 발생량(10.43ppm)이 비첨가구 (11.76ppm)에 비하여 감소하였다(p<0.05). 본 연구결과로 미루어 볼 때, 이유자돈 사료 내 단백질 함량 감소 및 protease 첨가 시 자돈의 성장, 영양소 소화 율 및 분 중 유해가스 발생량 저감에 도움이 되는 것으로 판단되며 이로 인해 사료비 절감 및 환경 개선의 효과를 얻을 수 있을 것으로 사료된다.