Comparison survey of growth and survival rate of White leg shrimp in monoculture and polyculture system with Mullet in Gowatr earth pond- Chabahar, Iran

This investigation was conducted to survey the growth and survival rate, weight average, FCR, and harvestable white leg shrimp biomass during 107 days culture in mono and poly culture earth pond system with mullet fish. Nine 600 m2 earth ponds were prepared and stocked with 20 shrimp post larvae in each pond (mean weight 0.007 ±0.001 g) for three treatments (each with three replication). After 40 days, the mullet fish fingerlings collected from the Oman Sea (with mean weight 35 g) released to earth ponds with a density of zero (T1 as control), 2 (T2), 4 (T2) per 100m2. During the culture period, water temperature, dissolved oxygen, pH and salinity were measured. One way ANOVA results showed that there were significant differences between growth rate, shrimp biomass, FCR and abiotic parameters (P<0.05), but not for survival rate (P>0.05). The highest shrimp biomass was harvested from T3 (with 212 kg and a mean weight of 18.4 g individual shrimp) and the lowest (with 187 kg with a mean weight of 16.23 g individual shrimp) was from T1. However, there were no statistically significant difference in survivorship between treatments, but the highest survival percentage was observed in T3 (95.96%) and the lowest in T2 (94.5%). Duncan's test in FCR average showed no significance difference between T1 (the lowest FCR, 1.2 ±0.1) and T2 (P>0.05), but there was a significant difference between these two treatments and T3 (the highest FCR, 1.27 ±0.2) (P<0.05). The conclusion expressed that polyculture of white leg shrimp and mullet fingerlings in earth pond not only performed more shrimp production compare to mono shrimp culture system.