Effects of Varius Levels of Lipid, Kind of Oils and n3/n6 ratio on Growth, Survival and Body Composition of Narrow Clawed Crayfish, Astacus leptodactylus

• Main Authors: Vali Pur, A`li Reza, Musavi, A`bbas, Nosrati, Majid, Sayyad Burani, Mohammad, Omidvar, Sadeq, Qorbani, Saheb A`li, A`bedini, A`li, Daday Qandi, A`zamat, A`bbasi, Keyvan, Zahmat Kesh, A`sgar, Matin Far, Abbas
• Format: Publication
• Language: Persian
• Published: Tehran (Iran) Fisheries Research Institute of Iran 2008
• Subjects: ACEITE DE SOJA; ACUICULTURA; AGUA DULCE; ALIMENTACION; ALIMENTATION; AQUACULTURE; ASTACUS LEPTODACTYLUS; BESOIN NUTRITIONNEL; Bndar Anzali ( Iran ); CANGREJO DE RIO; CRAYFISH; CRECIMIENTO; CREVETTE; CROISSANCE; DECAPODA; EAU DOUCE; ECREVISSE; FEEDING; FRESHWATER; GAMBAS Y CAMARONES; Gilan ( Province ); GROWTH; HUILE DE SOJA; Inland Waters Aquaculture Institute; IRAN ISLAMIC REPUBLIC; IRAN REPUBLICA ISLAMICA; IRAN REPUBLIQUE ISLAMIQUE; LIPIDE; LIPIDOS; LIPIDS; NECESIDADES DE NUTRIENTES; NUTRITIONAL REQUIREMENTS; PRAWNS AND SHRIMPS; Sefid Rud Fisheries Research Station; SOYBEAN OIL

The research are conducted to assess the effect of 25 pure dietary of nitrogenous with different levels of lipid (4,7,10,13 and 16 %) and various proportion of Kilka oil in ratio of Soya bean oil ( n3/n6 EFA)(K0/S100, K30/S70, K50/S50, K70/S30 and K100/S0). The test followed a Randomized complete block design to 5×5 factorial experiment. Growth indices, molting, survival and the body composition of the test organism Astacus leptodactylus in size of 1-2 g ( 0+), and further than 9 g (1+) have been evaluated. Each treatment organized with 3 replicates and totally 75 rearing tanks involved. The period of each test being planned 8 weeks and the test organism housed in fiber-glass tanks of 100 l capacity with flowing water and aeration in tanks are supplied. Our results showed in culture the different weight of test crayfish whose need of lipid and essential fatty acid approximately were in equal. With increment of lipid level and increasing ratio of Kilka oil in proportion to Soya bean oil in experimental diets the indices of growth of juvenile crayfish including yearling crayfish concerning body weight, food conversion ratio, also molting and survival rate being improved. In a diet with nearly 10-13 % lipid and 100 % Kilka oil with rich in n3 fatty acids maximum improvement of vital factors being achieved that in comparison with a diet of 4 % lipid and 100 % Soya bean oil full in n6 fatty acids the difference in treatments were significant (p0.05). The results relevant to the biochemical variation in the body showed in juvenile crayfish with scaling-up of lipid and ratio of n3/n6 in diet the protein amount and the lipid in the test organism carcass also being enhanced, this phenomenon in a diet with 16 % lipid and 100 % Kilka oil reached to its peak. It is also in yearling crayfish with increment lipid level in diet protein level, lipid and carcass energy increased, meanwhile the ash level reduced. The highest protein level, lipid and ash of carcass have been observed in yearling crayfish linked with diet of 13,16 and 7 % of lipid and lowest occurred in a diet 4, 4 and 16 % lipid level, respectively, that their difference were significant (p0.05). With considering the ratio of n3/n6 EFA the highest level of protein, lipid and the least ash in yearling crayfish were relevant to the diets of K100/S0, K70/S30 and K100/S0, respectively.