Table 2. Water quality characteristics of inland saline water pond during culture of Macrobrachium cephalus and M.rosenbergii Parameter Year (2002) March April May June July Aug. Sept. Oct. Salinity (ppt) 1 1 12 1 1 1 1 12 8 1 1 12 Temperature (0C) 29.7 27.3 29.4 29.3 32.0 30.5 32.7 25.5 Dissolved Oxygen (mg/L) 8.7 7.9 9.2 8.8 7.1 10.1 8.9 9 Free carbon dioxide (mg/L) 0.6 1 .3 0 0.6 3.6 3.6 1 . 1 2.5 Total alkalinity (mg/L) 40 32.5 27.5 100 240 240 235 320 Total hardness (mg/L) 7600 9800 9300 4500 3600 3700 3700 1560 Calcium (mg/L) 725 601 570 601 561 641 601 400.8 Nitrate (mg/L) 0.2 0.4 0.2 0.4 1 .1 1 .2 1 .0 0.8 Phosphate (mg/L) 0.2 0.4 0.8 0.6 0.2 0.1 0.2 0.1 Ammonia (mg/L) 0.3 0.5 0.4 0.2 0.1 1 .0 0.8 0.5 Table 3. Specific growth rate, survival and yield of Macrobrachium rosenbergii in inland saline water of 8 ppt salinity under mixed culture with M.cepah/us for 198 days it affects P monodon. Excess calcium also was not observed to retard the growth of M. rosenbergii in this case. Although the maximum growth of M. rosenbergii was reported at <53 mg/L of CaCO3 Parameter Species hardness (Brown et al. 1991 ), Bartlett and EnkerM.rosenbergii M. cepha/us lin (1983) found that growth was not adversely affected by hardness levels between 940 and 1,046 mg/L CaCO3 at relatively low alkalinity. The present study suggests that inland saline water of 8-1 1 ppt salinity that is deficient in potassium has good potential for use in the culture M. rosenbergii. In the present trial, the survival of prawns was not very high but total biomass production including that of M. cephalus was good. The success Number stocked 2000 4000 Initial length (cm) 2.570 ± 0.072 Initial weight (g) Survival (%) 0.800 ± 0.125 23 0.184 ± 0.013 80 Final length (cm) Final weight (g) Total Yield (kg) 1 9.72 ± 0.630 85.58 ± 7.082 40 22.65 ± 0.845 209.885 ± 29.887 671 .61 of culture of M. rosenbergii in inland saline water at Bharatpur (area 5,044 km2 ), Rajasthan with 70 percent of the ground water of low to moderate salinity (Kalra and Sharma 1999) is conducive to commercial shrin1p fanning in the region. We Yield (kg/ha) Specific Growth Rate 160 2.36 2686.44 3.55 initially at 10 percent of body weight for 30 days and at two percent thereafter. Water depth was maintained by filling with saline water as required. No water exchange was undertaken during the culture period. Pond water quality was analyzed for salinity, dissolved oxygen, free carbon dioxide, total alkalinity, total hardness, nitrate, phosphate and ammonia (APHA 1980) every month (Table 2). Shrimp weights were obtained by sample netting at monthly intervals to adjust feeding rates. The crop was harvested after 198 days. Total survival, length and weight of the animals were recorded (Table 3). Postlarval M. rosenbergii attained an average weight of 85.58±7.082 (Figure 2). Total survival and specific growth rate were 23 percent and 2.36, respectively, which were similar to survival and growth in fresh and brackish water. Total yield of M. rosenbergii was 40.0 kg, while 671.6 kg of M. cephalus were harvested. Potassium deficiency in inland saline water did not affect survival and growth of M. rosenbergii as 12 MARCH 2007 need to further study the cumulative effect of salinity, potassium and calcium in inland saline water on the growth and survival of M. rosenbergii with the goal of achieving higher production levels. Notes 1Aquaculture Research Laboratory of CIFE, Matsya Bhawan, Rani Road, Ambamata, Udaipur-313 001, Rajasthan, India email : atulsalinewater@yahoo.co.in Acknowledgment The authors are thankful to Dr. S.C .Mukhe1jee, Director, CIFE, Mumbai for providing the facilities to undertake this work funded under a National Agricultural Technology Project of ICAR (Grant No. PAL/AED/026) and to Dr. N. P. Sahu, Senior Scientist, CIFE Mumbai for reviewing the manuscript.
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