Abstract
This study was conducted to examine the effect of Hwangto, Illite, and any other disease resistant materials as dietary supplements on the growth performance and immunity for growing period with 30 Hanwoo male calves weaned 75days in age. Feeding trial was conducted with 6 treatments(five heads/treatment), which were T1(Control), T2(Control + 2% Hwangto), T3(Control + 2% Illite), T4(Control + 0.04% Oligosacharides), T5(Control + 2% Charcoal powder) and T6(Control + 0.1% Chromium picolinate) for 120 days from three to seven months in age. The results obtained are summarized as follows; During the experimental period, average daily gains were 0.82 to 0.92kg, and were high in the order of T3, T6, T4, T5, T2 and T1. Especially the growth rate of calves for growing period was higher in Illite, chromium-picolinate and oligo- sacharides feeding groups than in any other groups. Average daily intakes and intake ratio to body weight of concentrates for 120days were 3.91 to 4.15kg(average 4.03kg) and 3.10 to 3.31% (average 3.21%), respectively. TDN intakes per kilogram gains were 3.20 to 3.57kg(average 3.35kg) and were smaller in the order of T5, T3, T6, T4, T2 and T1, respectively. Density of IgG in serum of calves measured by the IgG SDID Kit was 10.2 to 11.6mg/$m\ell$, and especially increase rate of IgG for experimental period was high in T3 and T5 by 6.9 and 2.8%, respectively. But incidence of disease was not found to be different by treatments. According to the above results it may be concluded that Illite is a sort of clay minerals increased the growth rate, feed efficiency and immunity of early weaned calves for growing period, but was not in unprocessed Hwangto.
한우 수송아지에 대한 육성기 항병력 증진물질 투여 효과를 구명하기 위하여 75일령에 이유된 한우수송아지 30두를 대상으로 사료내 항병력 증진물질 첨가 종류에 따라 6개 처리(T1: 관행사육, T2: 황토 2%첨가, T3: Illite 2% 첨가, T4: Oligosacharides 0.04% 첨가, T5: Charcoal powder 2% 첨가, T6: Chromium picolinate 0.1% 첨가)를 두어 3개월령부터 7개월령까지 120일간 사양시험을 실시한 결과, 처리구별 일당 증체량은 T3, T6, T4, T5, T2 및 T1이 각각 0.92, 0.90, 0.90, 0.88, 0.83 및 0.82kg으로 Illite 및 크롬은 이유직후 송아지의 성장발육에 영향을 미쳤으나 가공되지 않은 황토급여는 성장발육에 뚜렷한 효과가 없었다. 육성기 120일간 1일 평균 농후사료 섭취량 및 체중대비 섭취비율은 각각 3.91${\sim}$4.15kg, 평균 4.03kg 및 3.1${\sim}$3.31%, 평균 3.21%였고, 1kg 증체에 소요된 TDN 량은 3.20${\sim}$3.57kg, 평균 3.35kg으로 T5, T3, T6, T4, T2 및 T1 순으로 우수하였다. 송아지의 혈청 내 IgG 농도는 처리구별로 10.2${\sim}$11.6mg/$m\ell$ 내에서 변화하여 정상 축에서 볼 수 있는 범위 내에 있었지만, T3 및 T5는 개시시에 비해 각각 6.9 및 2.8% 증가하였으며, 질병발생은 처리구별로 뚜렷한 차이가 없었다. 이상과 같은 결과들로 볼 때, 점토광물인 Illite는 다른 항병력 증진물질과 마찬가지로 어린 송아지의 발육 및 사료이용성을 증진시키지만 가공되지 않은 황토의 급여는 발육 및 사료이용성에 뚜렷한 차이가 없는 것으로 나타났다.
