CAJ | 학술논문

本试验旨在研究饲粮中性洗涤纤维( NDF)水平对泌乳高峰期奶牛生产性能、营养物质表观消化率及血清指标的影响。选用8头泌乳天数为(50±15) d的泌乳高峰期荷斯坦奶牛,按照4×4拉丁方设计,4个处理分别饲喂NDF水平为25.05%、28.05%、31.22%和34.19%的4种饲粮；共进行4期试验,每期21 d,其中预试期14 d,正试期7 d。结果表明：1)随饲粮NDF水平的升高,奶牛干物质采食量、产奶量、乳糖产量、乳蛋白产量和氮利用效率线性降低( P<0.05)；乳脂率和乳尿素氮浓度线性增加( P<0.05)；饲料转化效率和乳脂产量呈线性增加的趋势( P=0.05)；乳蛋白率呈线性降低的趋势( P=0.08)；但4%标准乳产量、乳糖率变化不显著( P>0.05)。2)随饲粮NDF水平的升高,NDF和酸性洗涤纤维( ADF)的表观消化率线性增加( P<0.05)。3)随饲粮NDF水平的升高,血清葡萄糖、胰岛素浓度线性降低( P<0.05)；血清非酯化脂肪酸、β-羟丁酸及尿素氮浓度线性增加(P<0.05)；血清甘油三酯(P=0.06)和皮质醇(P=0.07)浓度呈线性增加的趋势；但血清总胆固醇浓度无显著变化( P>0.05)。综合得出,饲粮中25.05%和34.19%NDF对泌乳高峰期奶牛生产性能和能氮利用都有不利影响,28.05%NDF比31.22%NDF的饲粮能氮利用更为合理,生产性能更佳,建议泌乳高峰期奶牛饲粮NDF水平为28.05%。
본시험지재연구사량중성세조섬유( NDF)수평대비유고봉기내우생산성능、영양물질표관소화솔급혈청지표적영향。선용8두비유천수위(50±15) d적비유고봉기하사탄내우,안조4×4랍정방설계,4개처리분별사위NDF수평위25.05%、28.05%、31.22%화34.19%적4충사량；공진행4기시험,매기21 d,기중예시기14 d,정시기7 d。결과표명：1)수사량NDF수평적승고,내우간물질채식량、산내량、유당산량、유단백산량화담이용효솔선성강저( P<0.05)；유지솔화유뇨소담농도선성증가( P<0.05)；사료전화효솔화유지산량정선성증가적추세( P=0.05)；유단백솔정선성강저적추세( P=0.08)；단4%표준유산량、유당솔변화불현저( P>0.05)。2)수사량NDF수평적승고,NDF화산성세조섬유( ADF)적표관소화솔선성증가( P<0.05)。3)수사량NDF수평적승고,혈청포도당、이도소농도선성강저( P<0.05)；혈청비지화지방산、β-간정산급뇨소담농도선성증가(P<0.05)；혈청감유삼지(P=0.06)화피질순(P=0.07)농도정선성증가적추세；단혈청총담고순농도무현저변화( P>0.05)。종합득출,사량중25.05%화34.19%NDF대비유고봉기내우생산성능화능담이용도유불리영향,28.05%NDF비31.22%NDF적사량능담이용경위합리,생산성능경가,건의비유고봉기내우사량NDF수평위28.05%。
This experiment was conducted to investigate the effects of neutral detergent fiber ( NDF) levels in diet on milk performance, nutrient apparent digestibility and serum indices of dairy cows during peak lactation period. Eight Holstein dairy cows [(50±15) days in milk] were selected in a 4×4 Latin square design. The NDF level in diets was 25.05%, 28.05%, 31.22% and 34.19%, respectively. The experiment had 4 periods with 21 days per period, and each period had 14 days for pre-test and 7 days for formal test. The results showed as follows:1) with the increase of NDF level in diet, the dry matter intake, milk yield, lactose yield, milk protein yield and nitrogen efficiency decreased linearly ( P<0.05); milk fat percentage and milk urea ni-trogen concentration increased linearly ( P<0.05);feed efficiency and milk fat yield tended to increase linearly ( P=0.05); milk protein percentage tended to decrease linearly ( P=0.08);while 4% fat corrected milk yield and lactose percentage were not significantly influenced ( P>0.05) . 2) With the increase of NDF level in diet, the apparent digestibility of NDF and acid detergent fiber increased linearly ( P<0.05) . 3) With the increase of NDF level in diet, serum glucose and insulin concentrations reduced linearly ( P<0.05); serum non-esterified fatty acids, β-hydroxybutyrate and urea nitrogen concentrations increased linearly ( P<0.05); serum triglycer-ide ( P=0.06) and cortisol concentrations ( P=0.07) tended to increase linearly, but total cholesterol concen-tration was not significantly influenced ( P>0.05) . In conclusion, both the 25.05% NDF and 34.19% NDF in diet have negative influence on energy-nitrogen utilization and milk performance, while the 28.05% NDF level can be more reasonable for nitrogen utilization and better milk performance than 31.22% NDF. It is suggested that the supplemental level of NDF be 28.05% for dairy cows in the peak lactation period.