西藏日喀则地区不同品种全株玉米青贮的营养价值评定

Evaluation on Nutritional Values of Different Corn Varieties Whole Silage in Xigaze

本试验旨在通过对西藏日喀则地区不同品种全株玉米青贮的营养价值评定,为西藏地区青贮玉米品种的选择提供参考。试验选取5个常见的玉米品种(鲁单258、鲁单267、中玉335、荣玉1609、荣玉1610)种植于西藏,蜡熟期收割制作裹包青贮,发酵120天后评定其营养成分、能量价值和发酵品质。结果表明:不同品种玉米青贮的营养成分含量和能量价值存在显著差异,荣玉1610的粗蛋白和总可消化养分含量最高,荣玉1609的淀粉含量和泌乳净能最高;在发酵品质方面,荣玉1609青贮的pH值最低,而乳酸含量、发酵系数和费氏评分显著高于其他品种玉米青贮。通过隶属函数分析,5个品种全株玉米青贮的综合营养价值由高到低分别为:荣玉1609>荣玉1610>鲁单267>中玉335>鲁单258。综上所述,荣玉1609的全株玉米青贮品质最优,其次为荣玉1610,但日喀则地区青贮玉米品种的选择,需要进一步结合其生物产量进行综合评定。

This study evaluated the nutritional values of different corn varieties whole silage in Tibet,and was aimed at providing references for the selection of silage corn varieties.Five common corn varieties(Ludan 258,Ludan 267,Zhongyu 335,Rongyu 1609 and Rongyu 1610)were selected to plant in Tibet.Bale silage was made at the dough stage and their nutritive values,energy prediction and fermentation quality were evaluated after 120 days for fermentation.The results indicated that the nutritional ingredient contents and energy values had significant differences among different corn varieties.Rongyu 1610 had the greatest contents of crude protein and total digestible nutrients.Rongyu 1609 had the highest starch content and net energy for lactating cow.For the fermentation quality,Rongyu 1609 had the lowest pH value,but its lactic acid content,fermentation coefficient and fleig scores were significantly higher than the others.By further analyzing the membership function,the values of comprehensive nutrition ranged from high to low was Rongyu 1609,Rongyu 1610,Ludan 267,Zhongyu 335 and Ludan 258.In conclusion,the corn silage of Rongyu 1609 was the best in quality,followed by Rongyu 1610.Moreover,the selection of silage corn varieties in Xigaze area needed to be combined with the biomass yield for comprehensive evaluation.