The effect of different levels of synthetic and algal astaxanthin (Heamatococcus pluvialis) on some biochemical parameters of blood serum in Rainbow trout broodstock Oncorhynchus mykiss (Walbaum, 1792)

The main objective of this study was to evaluate some health indices in rainbow trout (O. mykiss) broodstock via enhancing their food quality by adding two sources of astaxanthin (synthetic and algae) in feed.. 7 groups consisting of 6 treatments of two different astaxanthin levels and sources and a control (without astaxanthin) were considered. So, algal astaxanthin (Haematococcus pluvialis) in the three levels of 2.67, 3.55 and 8 gr/kg food (T1,T2, T3) and synthetic source in three levels of 40, 80 and 120mg/kg food in diet (T4, T5, T6) were examined on trout broods (3-4 years) for 120 days before the spawning season. Significant difference was observed among the treatments in terms of health-related blood factors. The broods which were fed with algal astaxanthin had lower blood sugar. Changes in albumin revealed that with the increase in astaxanthin the albumin level was increased first and then decreased. While the change in serum globulin treatments containing synthetic astaxanthin was not regular, it was so in algal astaxanthin. Overall, the results asserted that the application of astaxanthin improves health indices of rainbow trout broodstock. It also concluded that algal astaxanthin (Haematococcus pluvialis) for the reason that it contains supplementary nutritious, is extraordinary preferable than synthetic astaxanthin to improve health indices of rainbow trout broodstock.