우리나라에서 사육되고 있는 젖소 육성우의 분뇨배설량을 구명하기 위하여 육성우 6두를 공시하여 축산연구소 낙농우사에서 봄, 여름, 가을, 겨울 등 4계절에 걸쳐 각각 10일간 시험을 수행하였으며, 그 결과는 다음과 같다. 1. 건물섭취량은 평균 6.7kg으로 봄, 여름, 가을 및 겨울이 각각 4.6, 8.3, 7.1, 6.8kg으로 봄이 가장 낮은 섭취량을 보였으며, 음수량은 평균 $19.3{ell}$로, 여름이 $21.8{ell}$로 가장 많았고 봄과 겨울이 $18.3{ell}$로 낮았으나 계절별 유의차는 보이지 않았다. 2. 분뇨배설량을 계절별로 조사한 결과, 봄 13.7kg, 여름 23.8kg, 가을 25.0kg, 겨울 20.2kg으로 봄이 가장 낮았으며(p<0.05), 전체 평균 분뇨배설량은 20.3kg이였고, 체중대비 분뇨의 비율은 5.6%였다. 3. 체중과 분뇨배설량간($R^2=0.7816$), 체중과 사료섭취량간($R^2=0.7296$)의 상관관계가 비교적 높았으나, 음수량과 분뇨배설량, 사료섭취량과 분뇨배설량간의 상관관계는 비교적 낮았다. 4. 분뇨의 수분 및 pH를 분석해 본 결과, 분의 뇨의 평균 수분 함량은 각각 83.5, 94.6%였으며, pH는 각각 7.4, 7.6 수준이었다. 5. 분뇨중 오염물질 농도는 분의 $BOD_5,;COD_{Mn}$, SS, T-N 및 T-P는 각각 18,048, 50,114, 119,833, 2,519, $427mg/{ell}$였고, 뇨는 각각 5,434, 6,550, 825, 3,616, $28mg/{ell}$였다. 6. 분뇨중 비료성분은 분의 N, $P_2O_5,;K_2O$가 각각 0.25, 0.10, 0.14%였고, 뇨는 각각 0.36, 0.006, 0.31%였다.
This study was conducted to determine the volume of Holstein heifers manure excreted and its characteristics. The average dry matter intake of heifers was 6.7 kg/head/day. The intake rate was lowest in spring among four seasons. The average dry matter intake rate during spring, summer, fall, and winter was 4.6, 8.3, 7.1, and 6.8 kg/head/day, respectively. The average water intake of heifers was $19.3{ell}/head/day$. The wale. consumption was highest value ($21.8{ell}/head/day$) in summer and lowest values ($18.3{ell}/head/day$) in spring and winter. Values were found not to be statiscally different for the four seasons. The average manure production of heifers (average live weight was 363.1 kg) was 20.3 kg/head/day and it was 5.6% of live animal weight. The manure production during spring, summer, fall, and winter was 13.7, 23.5, 25.0, and 20.2 kg/head/day, respectively. Production during spring was lower than the other seasons (p<0.05). A higher correlation between live weight and manure production ($R^2=0.7816$) and between live weight and feed intake ($R^2=0.7296$) was observed for heifers. Correlations between manure production and water intake and between manure production and feed intake were found to be relatively low for heifers. The moisture content of feces was 83.5% and that of urine 94.6%. The pH of feces and urine were in the ranges of 7.4 and 7.5, respectively. The $BOD_5$, COD, SS, T-N, T-P concentrations of the heifer feces were 18,048, 50,114, 119,833, 2,519, and $427mg/{ell}$, respectively. Heifer urine showed lower levels of $BOD_5(5,434mg/{ell})$, COD$(6,550mg/{ell})$, SS$(825mg/{ell})$, T-N$(3,616mg/{ell})$, and $T-P(28mg/{ell})$ than feces. The fertilizer nutrient concentrations of heifer feces was 0.25% N, 0.1% $P_2O_5$ and 0.14% $K_2O$. Urine was found to contain 0.36% N, 0.006% of $P_2O_5$ and 0.31% $K_2O$.
