Crop rotation as a better sanitary practice for the sustainable management of Litopenaeus vannamei culture

Abstract

In the present study, finfishes (Mugil cephalus and Chanos chanos) were cultured between crops of Litopenaeus vannamei shrimps for crop rotation and the reduction in the incidence of shrimp diseases was observed. The fish seeds of 5-7 g individual weight were collected from the wild and required numbers were sorted out and stocked in the ponds at the rate of 7000 and 8000 numbers of Mugil cephalus and Chanos chanos, respectively in 1.3 ha. For shrimp culture, the seeds were purchased from a reputed hatchery and were stocked at a density of 7.7 shrimps m -2. In the control pond, the shrimps were stocked at the same density. The first crop was a fish culture experiment for 6 months followed by a shrimp culture experiment for 4 1/2 months in one pond and the other pond was used as control and two shrimp culture experiments were carried out. During the culture period, the water quality parameters such as, temperature, salinity, pH, transparency, dissolved oxygen, ammonia, nitrite, nitrate, phosphate, silicate and the microbial load were analyzed. While comparing the performance of shrimps in the experiment pond and control pond, experimental shrimp pond yield was interesting with 695.3 kg of more production, similarly survival rate was 25% higher, Average Body Weight (ABW) was 2.9 g higher and Average Daily Growth (ADG) was 0.16 g higher for 90 days of culture. The results of the study have clearly established the advantages of crop rotation with fish than continuous culture of shrimps in the same system.