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1988年龚关在10亩成鱼池中套养鳜鱼种350尾,规格12～18cm,重28公斤。年底收鳜鱼260尾,重127公斤,平均亩净产9.9公斤。成鱼亩净产870公斤,比1987年增产87.5公斤。在此基础上,1989年套养鳜鱼种增至500尾,规格则降至7.5～11.4cm,重15公斤。年终收鳜鱼410尾,重153.5公斤,亩净产13.85公斤。成鱼亩净产901.5公斤。两年套养结果表明,成鱼池套养鳜鱼具有增产增收效果,主要经验如下: 1.合理套养1988年池塘干池起捕中发现,池中仍然有少量野杂鱼,但是夏季套养下池的小草鱼种几乎没有了,而当时出池鳜鱼87%条重超过0.5公斤。分析原因主要是投放鳜鱼种尾数少规格大,池中野杂鱼多,其饵料充足生长快,鳜鱼个体越大摄食对象也大一些,夏季套养的小草鱼种(9～12cm)相对野杂鱼又要易捕食些,从而降低了鳜鱼对野杂鱼的利用率。针对上述情况,1989年套养的鳜鱼在数量、规格上作了相应变动,草鱼套养规格则都在12cm以上。结果年底起鱼时草鱼种出塘率达76%(18cm),鳜鱼条重多在0.35公斤以下,只有14%达0.5公斤,从而提高了其对野杂鱼的利用。2.设食场诱野杂鱼集中
In 1988 Gong Guan in 10 acres of adult fish pond raised 350 species of mandarin fish, size 12 ~ 18cm, weight 28 kg. At the end of 260 catfish, weighing 127 kilograms, the average net yield of 9.9 kilograms. The net production of adult fish mu 870 kg, 87.5 kg more than in 1987. On this basis, the number of nursery larvae raised to 500 in 1989, while the specifications dropped to 7.5 to 11.4 cm and 15 kg. The end of the year received 410 tuna, weighing 153.5 kilograms, 13.85 kilograms of net net output. Into a fish net profit of 901.5 kilograms. Two years of nursery results show that into the fish pond nursery stock raising yield, the main experience are as follows: 1. Rational nursed back to the pond in 1988, found in the dry pond, the pool is still a small amount of wild trash, but the summer nursery Small grass carp species in the pool is almost gone, but at that time out of the pool catfish 87% weight more than 0.5 kg. The main reason for the analysis is that the number of mandarin fish put into small size is large, the number of wild fish in the pond is large, and its bait is enough to grow fast. The larger the mandarin fish, the larger the males are, the smaller (9-12cm) Trash and easy to prey on some, thereby reducing the utilization rate of wild fish on wild catfish. In response to the above situation, the number of captive mandarin fish raised in 1989 and the specifications have been changed accordingly. Grass carp cultivation specifications are all above 12 cm. Results At the end of the year, grass carp species reached 76% (18cm) and the percentage of skipjack tuna exceeded 0.35kg and only 14% reached 0.5kg, thus increasing its utilization of wild trash fish. 2. Set food traps wild fish concentration