Abstract:

The effect of raining and drying method on the quality of alfalfa hay was studied. The results showed that after raining the water soluble carbohydrate (WSC) content and RFV (relative feed value) of alfalfa hay decreased, while the content of neutral detergent fiber (NDF) increased. The content of crude protein (CP), acid detergent lignin (ADL) and the acid detergent fiber (ADF) were not significantly different between raining and non-raining treatments. Under oven and sun drying method, CP and WSC content of alfalfa hay increased, the relative feed value also increased, while the ADF content decreased. The drying method had no significant effect on NDF and ADL content of alfalfa hay. The interaction effect of raining and drying method significantly affected the nutrient content and RFV of alfalfa hay. The CP, WSC and RFV of non-raining×oven drying treatment was the highest among all the treatments, and the NDF, ADF and ADL content of non-raining×oven drying treatment was the lowest. Overall, the quality and relative feed value of non-raining alfalfa was higher than raining alfalfa, and the quality of alfalfa under the oven dry method was the best, sun drying the second, shade drying the last.

Key words: Raining, Drying method, Alfalfa, Hay, Nutrient content, Relative feed value

摘要：

在紫花苜蓿（Medicago sativa L.）收获调制期间，极易遭遇雨淋，雨淋及干燥方式对紫花苜蓿干草品质的影响较大。本研究以未雨淋和雨淋紫花苜蓿为对象，分别对其进行烘干、晒干和阴干处理，并分析紫花苜蓿干草的营养品质。结果表明：雨淋后紫花苜蓿的中性洗涤纤维含量显著升高，水溶性碳水化合物含量显著降低，相对饲用价值降低；雨淋对紫花苜蓿干草粗蛋白、木质素和酸性洗涤纤维含量没有显著影响。经烘干和晒干处理的紫花苜蓿干草粗蛋白、水溶性碳水化合物含量及相对饲用价值显著高于阴干处理，酸性洗涤纤维含量则是烘干和晒干处理显著低于阴干处理；干燥方式对紫花苜蓿干草中性洗涤纤维和木质素含量没有显著影响。雨淋和干燥方式的交互作用显著影响了紫花苜蓿干草的营养成分和相对饲用价值，未雨淋×烘干处理下的粗蛋白、水溶性碳水化合物含量及相对饲用价值最高，中性和酸性洗涤纤维及木质素含量最低。总之，未雨淋紫花苜蓿的品质和相对饲用价值高于雨淋后的紫花苜蓿。干燥方式以烘干最能保存紫花苜蓿的品质，其次是晒干，效果最差的干燥方式为阴干。遭受雨淋后，采用烘干和晒干的方式能较好的保存紫花苜蓿干草营养成分。

关键词: 雨淋, 干燥方式, 紫花苜蓿, 干草, 营养成分, 相对饲用价值