Đánh giá hiệu quả của mô hình nuôi tôm thẻ chân trắng (<i>Litopenaeus vannamei</i>) bán thâm canh cải tiến tại Quảng Ngãi

Abstract

     Semi-intensive culture of white-leg shrimp was carried out in Duc Chanh commune, Mo Duc district, Quang Ngai province. Model treatment included three grow-out ponds 2.000 m²/pond. Shrimps were nursed in 35 days before transferring into grow-out ponds. The inlet water was settled and treated with chlorine. Probiotics were provided into ponds every five days during culture period, shrimps were partially harvested. Control treatment comprised three 2000 m²/ponds, shrimps were directly cultured in grow-out ponds without nursing phase; inlet water was not treated; water quality in ponds were managed by using chemicals, drugs, and sometime probiotics, shrimps were fully harvested once time. The result showed that water quality in model ponds were managed in suitable range for the growth and development of shrimp, whereas fluctuated values of DO, TAN and NO₂^-N were recorded in control ponds. Shrimps in model ponds reached market size of 21.24 ± 1.41 g/individual after 65-75 days, being significantly higher than 19.41 ± 0.61 g/individual obtained from control ponds after 98-110 days (P<0,05). Survival, productivity and profit gained in model ponds were 84.58 ± 4.46%, 13.42 ± 0.85 ton/ha and 574.15 ± 147.69 million dong/ha, respectively. These values were higher than that of control ponds with 68.13 ± 18.81%, 10.42 ± 1.97 ton/ha and 306.29 ± 333.85 million dong/ha, respectively. The result semi-intensive shrimp culture with nursing phase and probiotic supplementation improved the water quality and productive efficiency in white-leg shrimp farming.

Key words: White-leg shrimp, semi-intensive, probiotics, nursing phase