2021.12.03 - 2039 viewed
This study was conducted to evaluate the effects of culture form and density on survival, growth, yield and economic efficiency of commercial clams in the waters of Van Don, Quang Ninh. Tuna with an initial length of 18.36 mm/head and an average weight of 4.12 g/head were used as initial research materials. Two farming methods were arranged: cage culture (basket) hanging on rafts (including experiments TN1, TN2, TN3 and TN4) and cage culture placed on tidal flats (including experiments TN5, TN6, TN7 and TN8). for each culture, there were 4 formulas for stocking density of 25 fish/cage (100 fish/m2) (TN1, TN5), 35 fish/cage (140 fish/m2) (TN2, TN6); 45 fish/cage (180 fish/m2) (TN3, TN7); and 55 animals/cage (220 animals/m2) (TN4, TN8), each experimental treatment was repeated 3 times. After 12 months of experimental culture, the results showed that the density and form of rearing had an effect on growth, survival rate and commercial yield. Tumor growth ranged from 28.76 to 41.74g, length ranged from 51.17 to 72.69 mm, survival rate fluctuated from 57.4 to 78.3%, the highest growth was in the formula with density of 25 fish/cage, the difference between treatments was statistically significant (p ≤ 0.05). The average yield of commercial pods increased with the increase of stocking density, ranging from 21.7 to 38.3 tons/ha, the difference was statistically significant (p ≤ 0.05). However, economic accounting shows that the economic efficiency is highest in TN2 when raising cages in the form of hanging cages on rafts and stocking at a density of 35 fish/cage (140 fish/m2). In this formula, average growth in weight and length was obtained at 38.91g and 68.47 mm, survival rate was 76.4%, yield was 32.9 tons/ha, and profit was obtained. reached VND 0.883 billion and the profit margin reached 28.1%. From the research results, it can be recommended that farmers stock with a density of 35 fish/cage.
| File: | BaiBao_KHTN_Thang11_2021.pdf | Tải về |
