Effect of synthetic and algal astaxanthin on the reproduction efficiency of female rainbow trout (Oncorhynchus mykiss)
Subject Areas : New Technologies in Aquaculture Development
Keywords: egg quality, Keywords: Rainbow trout, Astaxanthin, Haematococcus pluvialis, Reproduction efficiency,
Abstract :
Abstract This research was conducted in a trout farm in Kohkiloyeh and Boyer-Ahmad Province. The main object of this study was comparing of two sources of astaxanthin (synthetic or algae, Haematococcus pluvialis) in feed on reproduction efficiency of rainbow trout. So, algal astaxanthin (Haematococcus pluvialis) in the three levels of 2.67, 3.55 and 8gr/kg food (T1,T2, T3) and synthetic source in three levels of 40, 80 and 120mg/kg food in diet (T4, T5, T6) examined on 140 trout broods (3-4 years) for 4 months, before the spawning season. Therefore, it was considered 7 groups consisting 6 treatments of two different astaxanthin sources and a control (without astaxanthin). Reproduction efficiency analyzed through reproduction indices such as egg diameter, fecundity, fertilization, survival, hatching and eyed egg rates. Significant difference between treatments in terms of fecundity, eyed eggs rate and the number of eggs per gram was observed (p<0.05). Although in some factors such as egg diameter and fertilization rate, no significant differences was observed. By increasing level of astaxanthin in both sources of algal and synthetic, hatching and eyed egg rates increased from 40mg/l to 120mg/l, but the effect of alga source on these indices was more perfect. Considering the results, the best result related to treatment of 8gr/kg alga (T3). Observations during this research indicated no disease and mortality and also proper coloration and freshness of fishes. Overall the results asserted that the application of astaxanthin improves reproduction performance of rainbow trout. It also concluded that natural astaxanthin (Haematococcus pluvialis) for the reason that contains supplementary nutritious, is extraordinary preferable than synthetic astaxanthin to improve reproductions indices and egg quality of female rainbow trout.
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