The combined effect of vitamin E, arachidonic acid,Haemtococcus pluvialis, nucleotides and yeast extract on growth and ovarian development of crayfish (Cherax quadricarinatus) by the orthogonal array design

The red claw (RC) crayfish (Cherax quadricarinatus) is one of the most important farmed freshwater crustacean species for its high palatability, market value and consumer preference. Understanding the role of diets in maturation can help to overcome some of the challenges to reproduction. Optimal effect of dietary vitamin E (VE) supplementation, Arachidonic acid (ARA), Haemtococcus pluvialis (H.P) nucleotide (NT) and yeast extract (YE) on the growth and ovarian development of RC crayfish is determined in the present study. The range analysis of a L16 (45) orthogonal array design arranged five factors varied at four levels (VE of 40, 160, 240 and 320 mg/kg; NT of 2, 4, 6 and 8 g/kg; H.P of 2, 4, 6 and 8 g/kg; ARA of 5, 10, 15 and 20 g/kg; and YE of 2.5, 5, 10 and 15 g/kg) revealed that the highest weight gain (WG), feed conversion ratio (FCR) and gonadosomatic index (GSI) of the crayfish occurred at VE of 240 mg/kg, NT of 8 g/kg, H.P 4 g/kg, ARA of 5 g/kg and YE of 10 g/kg, and the maximum hepatosomatic index was observed at VE of 40 mg/kg, NT of 4 g/kg, H.P of 4 g/kg, ARA of 10 g/kg and YE of 5 g/kg. Furthermore, analysis of variance demonstrated that all the five factors had significant effects on WG, GSI and FCR. In contrast, any of these factors did not have a significant influence on the hepatosomatic index and SR. These results proposed that dietary contains VE of 240 mg/kg, NT of 8 g/kg, H.P of 4 g/kg, ARA of 5 g/kg and YE of 10 g/kg might be the optimal combinations for the growth and ovarian development of RC crayfish.