Zeitschrift für Aquakulturforschung und -entwicklung

Abstrakt

Effect of Mineral Deposition on Shrimp Litopenaeus vannamei in High Alkaline Water of Pennar River, Andhra Pradesh of Southeast Coast of India

Alagarsamy Sakthivel,Periyasamy Selvakumar,Ayyaru Gopalakrishnan*

The Litopenaeus vannamei is one of the most important economical shell fish in throughout the world. Mineral deposition is a continuous problem in Litopenaeus vannamei culture pond in world wild. The current study to compares the water quality parameters, shrimp growth biomass, and mortality rates during harvest between three ponds. Experimental setup was selected three different ponds (brackish water pond, bore well pond, and bore well resevoir pond) were seeded with the same density of the Litopenaeus vannamei at Pennar River Andhra Pradesh, south India. The primary differences between the ponds were as the water source; one pond was filled from the estuary, estuarine-water was fed to the pond, the second one was taken from bore wells with high alkalinity, and there’d one filled from bore well resevoir pond. Temperature in three ponds was varied and it reached up to 29.6°C after 125 days of culture. Dissolved oxygen (DO) levels were varied within the acceptable range although levels in the alkaline pond were as near the lower limit in the last 90 days before harvest. Salinity levels were varied in three ponds, above optimal levels and increased over the 120 days. Alkalinity in the estuarine water was typically <100 ppm and whereas (275-399 ppm) in the alkaline pond. In the alkaline pond, beginning on 75th day the mineral deposits was observed all parts of shrimp over the body and it’s including the eye and the inner gill chambers after harvest, 42% of the shrimp showed this coating. The initial stages of the mineral deposits on shrimps showed pale yellow colour. Elemental analysis identified the major constituents was present in the sample as Manganese, Sodium, Chlorine, Magnesium, Aluminium, Silica, Iron and Calcium. Survival rates of shrimps in the estuarine-waterfed pond was 92% with a total pond biomass at harvest was 1.65 tons ha-1 compared to survival rates of 79% in the alkaline pond and a biomass at harvest was 1.020 tons ha-1. When quality water may be used, its alkalinity should be monitored and diluted with water from other sources.