我场是“北京黑猪”育种中心场之一。过去,由于我们对饲料生产重视不够,90多亩饲料地大部分都种了玉米、高粱、甘薯等粮食作物,很少种青饲料。青饲料主要靠从外面购买,因供应没有保证,大小猪经常吃不上青料,引起大猪便秘,仔猪拉稀,哺乳期母猪不下奶,猪群发病率高。经过无产阶级文化大革命,我 My field is “Beijing black pig” breeding center field. In the past, due to the fact that we did not pay enough attention to feed production, most of the 90 mu of feedstuff was planted with food crops such as corn, sorghum and sweet potato, and few green fodder. Green feed mainly by buying from the outside, because there is no guarantee of supply, large and small pigs often eat green material, causing large pigs constipation, piglets diarrhea, lactating sows under the milk, the high incidence of herds. After the Great Proletarian Cultural Revolution, I