Comprehensive use of cow dung is more cost-effective than raising and selling cattle

    Wang Shuizhang of Zhengzhou, Henan Province, built an ecological park. In this ecological park, Wang Shuizhang not only raised chickens but also did aquaculture, and planted fruit trees and vegetables, obtaining multiple kinds of income. All of this can be attributed to a common agricultural waste—cow dung.

    Wang Shuizhang is a beef cattle farmer and raises 1,000 cattle. In the past, cow dung and cow urine were everywhere in the farm, and the stench filled the air. With cow dung all over the ground impossible to deal with and polluting the environment, Wang Shuizhang collected all the cow dung and urine and built a biogas digester. With the biogas digester, the biogas produced could be used for cooking. Once the biogas was put to use, it could also generate electricity, so cooking and using electricity cost no money.

    The biogas produced from fermented cow dung was put to use, but the remaining biogas slurry and biogas residue were too much in quantity. Wang Shuizhang racked his brains again, diluted the biogas residue and biogas slurry, and began raising loaches, which are tolerant of sewage and low oxygen. Through exploration, he mastered the appropriate ratio for using biogas residue and biogas slurry. The loaches he raised grew 20% faster than those under ordinary farming methods. The loaches he raises now are in short supply. Not only is there no worry about selling them domestically, but they are also exported to South Korea, Japan and other places. Moreover, the loach itself is a aquatic product with relatively high economic value and a relatively high price. Raising one mu of loach can earn at least 20,000 yuan.

    In loach farming, the old water is replaced at intervals, and new water diluted with biogas residue and biogas slurry is added in a certain proportion to ensure the content of nutrients in the water. Wang Shuizhang did not waste the old water that was replaced. He used it to raise bighead carp and silver carp. Moreover, without feeding any feed at all, the fish still grew big and good. Now Wang Shuizhang had one more source of extra income. In addition, the water in the fish pond could be reused. Using it to irrigate the land saved both water and fertilizer. After cow dung is fermented, its full comprehensive utilization can produce benefits more than 20 times that of cattle farming.