Abstract

We evaluated the impact of a combined vitamin E (vit E), a mixture of nucleotide (mixed-NT), Haematococcus pluvialis (H. pluvialis) , arachidonic acid (AA), and yeast extract powder (YEP) supplementations on the relative mRNA expression of reproduction and antioxidant-related genes in red claw crayfish Cherax quadricarinatus using an orthogonal design (L16 4 5 ) plus control diet for 70 days feeding trial. Five factors with four levels: A, vit E 40, 160, 240, and 320 mg/kg diet ; B, mixed-NT 2, 4, 6, and 8 g/kg diet ; C, H. pluvialis 2, 4, 6, and 8 g/kg diet ; D, AA 5, 10, 15, and 20 g/kg diet ; E, YEP 2.5, 5, 10, and 15 g/kg diet were studied. The relative mRNA expression of reproduction-related genes (vitellogenin ( vtg ) and fatty acid-binding protein ( fabp )), and antioxidant-related genes (heat shock protein 70 ( hsp70 ), glutathione peroxidase ( gpx ), glutathione S-transferase ( gst ), mitochondrial manganese superoxide dismutase ( mmnsod ), and ferritin ) in hemocyte, hepatopancreas, and ovary tissues were measured. There was a major depression in gene expression levels throughout the experimental diet at high vit E 320 mg/kg level with other factors. Expression of antioxidant enzyme genes significantly increased in treatments of T9, T10, T11, and T12, while significantly decreasing in treatment of T13 and other treatment groups with high vit E 320 mg/kg levels with the other factors. Gene expression of vtg and fabp demonstrated similar patterns to those of antioxidant genes. These results provide evidence that combined supplementations of vit E, mixed-NT, H. pluvialis , AA, and YEP with vit E 240 mg/kg , mixed-NT 8 g/kg , H. pluvialis 4 g/kg , AA 5 g/kg , and YEP 10 g/kg may present a novel strategy for improving reproduction performance and antioxidant activities in RC-crayfish, C. quadricarinatus by the positive impact on the