Bài báo khoa học

Shrimp farming applying Copefloc technology (Copepoda - biofloc) is an improved technology of biofloc by combining the farming of zooplankton biomass as food for shrimp while reducing feed costs and limiting environmental fluctuations. country. The study was carried out in the shrimp farming area of Dien Kim commune, Dien Chau district, Nghe An with 2 treatments (NT), each treatment was repeated 3 times. In which, NT1 raised shrimp using copefloc technology, and NT2 (control) raised shrimp with little water change, using industrial feed entirely. The results showed that: temperature, pH, clarity, dissolved oxygen (DO), salinity, in the two treatments were not much different, the fluctuations of the above factors were within the allowable limit for shrimp farming. white foot card; alkalinity in copefloc ponds is more stable; total ammonia nitrogen (TAN) and NO2- were much lower than the control treatment and the difference was statistically significant. The number of algae in ponds applying Copefloc technology (71 species) was higher than that in conventional technology ponds (62 species), in which Bicillariophyta (Silicon algae) predominates. The composition of zooplankton species in Copefloc technology ponds has a richer number of species (45 species) than in control ponds (41 species), in which the copepod group accounted for the largest proportion. The biofloc composition of shrimp ponds using copefloc technology through parameters of FVI (floc volume), TSS (total suspended solids) and VSS (volatile suspended solids) were much higher than those of treated ponds. control, the above indicators were statistically significant difference between the two rearing treatments