INVESTIGATION OF LITOPENAEUS VANNAMEI CULTURE IN BRACKISH WATERS OF BAFGH, YAZD PROVINCE

This survey is part of the investigation on feasibility of introduction of Litopenaeus vannamei Boone, 1931 in shrimp culture industry of Iran. The objective was evaluation of the adaptation of the white leg shrimp, L. vannamei to brackish ground waters of the Bafgh area in Yazd province. Around 120000 shrimp postlarvae (PL7 & 15) were stocked in four 0.15ha earthen ponds (17 & 23 ind/m2) in July 2005 and the culture period took about four months. Physicochemical and biological factors were studied during the culture. Shrimps were fed with commercial feed of the L.vannamei. Results showed low survival (19.2%) and growth (2-2.5g mean body weight). Based on the assessments, the limnological factors were most unfavorable elements causing the low growth in the shrimp. Concentration of K, Ca, Mg and Na Fe (II & III), different heavy metals, nitrogenous compounds, water hardness and the season and thermal periods are probably the most essential factors affecting production yield of the shrimp because of underground origin of the water. Also, the structure of ponds and drainages, presence of invasive water plants and insects may have affected the survival and growth of the shrimp as well.