Hygienic, quantitative and qualitative monitoring of Salmo trutta caspius fingerling in Shahid Bahonar culturing and propagation complex in Mazandaran until their releasing to the Caspian Sea
Subject Areas : New Technologies in Aquaculture Development
Keywords: Caspian Sea, Keywords: Fingerlings, Releasing, Brown trout,
Abstract :
Abstract[1] This study has been conducted for duration of two years (2003-2004) with the aim of hygienic, quantitative and qualitative monitoring of fingerling fish (Salmo trutta caspius). A total of 118 brood stock fishes (Brown trout) were caught from opening place of Tonekabon River with an average weight of 2.35 kg. 79 of adult fishes were kept in fresh water fish farm to reach sexual maturity for duration of two months. During breeding time (along with other adults that were already kept from previous years), a total of 197 fishes were bred and the results were as follow: The average weight (kg) and length (cm) of propagated females were 2.33±0.92 and 56.4±1.54 respectively. But in males the average weight (kg) and length (cm) of propagated fishes were 2.35±13 and 60±0.86 respectively. At this time the males ratio number to females were 2:2 and the number of egg yield during propagation was 568989 (each matured female was holding 2888 of eggs). The average percentage of fertilization, eggs eyes survival and percentage of hatching survival were 97±0.86, 95±1.39 and 90±1.22 respectively. The total number of and percentage of larvae earned from obtainable eggs were 486523 and 85.5% respectively. The average larvae weight (after post hatching), larvae (mix feeding) and fry fishes (active feeding) were 96±10, 130±12, and 200±7 milligrams respectively. Therefore, food conversion in different weights were 96-130 mg :0.87, 130.200 mg:0.95, 200-400 mg:1,400-2000 mg:1.1,and for conversion of 1.4 need more than 5 grams respectively. The biometric factors on fingerlings are related to those fingerlings which their propagation happened during 2001 and 2002. Maximum and minimum weight, length and fat coefficient of one year class were 21.95 and 1 gram, 12.6 and 5.2 cm, 1.22 and 1.01 respectively. Maximum and minimum weight and length of two years class were 80 grams and 5 grams, 19and 3.8cm respectively. From parasitological point of view about 756 fingerlings with the weight of 1.95-20 grams were under consideration. In this connection the percentage of parasitic infestation such as gyrodactylus, myxobolus and scyphidia were 54, 14.2 and 13.8 respectively. The resistance of those fingerlings and direct exposure to 12.5 ppt (Caspian Sea water) for one-year and two-year classes were 53 and 100 percent. The physicochemical parameters in this survey for main entrance water to fish farm, stream and Tonecabon river water were determined as follows: TDS, EC, PH, DO, PO43-, NH4+, CO32-, BOD5, Ca 2+ and Mg 2+. * Corresponding Author; Email: aliasgharsaeedi@yahoo.com
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