包头地区紫花苜蓿最适收获期研究

Study on the optimum harvest period of alfalfa in Baotou

本文对不同收获期(不同茬次、不同花期)苜蓿干草调制过程中营养物质的含量和损失率进行了研究。结果表明:随着生育期的推迟,苜蓿鲜草的营养品质逐渐降低;天气晴朗的条件下,苜蓿干草叶片含量损失率为30.55%~38.26%,粗蛋白质(CP)损失率为22.73%~25.32%,中性洗涤纤维(NDF)、酸性洗涤纤维(ADF)损失率为25.28%~36.22%,相对饲喂价值(RFV)损失率为25.58%~36.83%,调制的干草品质较好;苜蓿干燥期间遭遇雨淋,苜蓿干草叶片含量损失率为47.04%~49.69%,CP损失率为55.66%~63.89%,NDF、ADF损失率为50%左右,RFV的损失率为50%以上,调制的干草品质相对较差。通过对营养物质含量及损失情况综合分析,筛选出包头地区苜蓿的适宜收获时期分别为第一茬初花期、第二茬现蕾期、第三茬初花期。

In order to provide the theoretical basis for high quality alfalfa hay production in Baotou,the nutrient contents and nutrients loss rate in the process of alfalfa hay in different harvest periods(different stubbles,different flowering periods)were studied to screen the optimum harvest period.The results showed that:with the delay of growth period,the nutritional quality fresh alfalfa gradually decreased;Under sunny weather,the loss rate of alfalfa hay leaves was 30.55%~38.26%,crude protein(CP)loss rate was 22.73%~25.32%,neutral detergent fibre(NDF)and acid detergent fiber(ADF)loss rate was 25.28%~36.22%,and relative feed value(RFV)loss rate was 25.58%~36.83%,the quality of the prepared hay was better;Alfalfa suffered from rain during the drying process,the loss rate of alfalfa hay leaves was about 47.04%~49.69%,CP loss rate was about 55.66%~63.89%,NDF and ADF loss rate was about 50%,and RFV loss rate was more than 50%,the quality of the prepared hay was relatively poor.Comprehensive consideration with nutrient contents of different harvest periods,the optimum harvest period of alfalfa in Baotou were initial flowering period of the first stubble,budding period of the second stubble and initial flowering period of the third stubble.