不同甜高粱品种生产与奶牛饲喂特性比较

试验使用饲用甜高粱Sorghum dochna辽甜1号、辽甜3号2个品种，在遵化试区试验点分2步同时进行，一是进行适应性及生物学产量测定，二是生物学产量测定以及奶牛饲喂效果对比试验，以期筛选出适合冀东地区奶牛优质牧草。结果表明，甜高粱在冀东地区种植生长性能良好，适宜种植密度6.00万～6.75万株/hm2，辽甜1号、3号干草产量分别可达到29.98～33.70和31.51～35.45 t/hm2。用不同青粗饲料牧草组合和相同精料补充料，等量干物质采食量饲喂奶牛试验，日产标准乳分别高于以玉米Zea mays秸青贮为主的对照组2.64和2.49 kg,乳中干物质、乳蛋白、乳脂肪含量无差异。辽甜1号、3号生物学产量高，适合奶牛青饲和制作青贮，是奶牛很好的青粗饲料。

Comparison of productivity and feeding characteristics of two sweet sorghums cultivars

Two sweet sorghum cultivars, Sorghum dochna cv. Liaotian No.1 and No.3, were used to test the features of adaptability and dairy cow feeding for high quality forage screening. The results showed that the two cultivars grown well in the east of Hebei Province and could be used as green roughage and silage. The suitable growth density was 60.0 to 67.5 thousand plants/hm2. The fresh matter yields of Liaotian No.1 and No.3 reached 29.98 to 33.7 t/hm2 and 31.51 to 35.45 t/hm2 respectively. The sweet milk yields of dairy cows fed with Liaotian No.1 and No.3 as the basic diet were 2.64 kg and 2.49 kg higher than that of maize silage (contents of dry matter, lactoproteid and milk fat were same). Liaotian No.1 and No.3 were excellent green roughage because it was easy to be utilized by green feeding and silage making, and its yield was high.