Effect of feeding with different sources of zinc supplements on reproductive indices of male rainbow trout broodstock (Oncorhynchus mykiss)

Document Type : Research Paper

Authors

1 Ph.D. Student of Aquaculture, Faculty of Marine Science and Technology, University of Hormozgan, Bandar Abbas, Iran

2 Associate Professor in Department of Fisheries, Faculty of Marine Science and Technology, University of Hormozgan, Bandar Abbas, Iran

3 Assistant Professor in Fisheries Research Institute of Iran, Shahid Motahari Clod-water Fish Genetics and Breeding Research Center, Yasouj, Iran

4 Associate Professor in Department of Fisheries, Faculty of Natural Resources, University of Kurdistan , Sanandaj, Iran

5 Assistant Professor in Department of Fisheries, Faculty of Marine Science and Technology, University of Hormozgan, Bandar Abbas, Iran

Abstract

In this study, the effect of feeding with different sources of zinc supplements on reproductive indices of male rainbow trout was investigated. Feeding treatments for 16 weeks of research period included: (1) male broodstock fed with diet containing 40mg/kg of inorganic zinc, (2) male broodstock fed with diet containing 40mg/kg of zinc nanoparticles, (3) male broodstock fed with diet containing 40mg/kg of organic zinc and (4) male broodstock fed with zinc-free diet (control). Breeding and fertilization were performed for different treatments using the control of female oocytes. The highest percentage of fertilization eyed eggs and hatched eggs were observed in rainbow trout broodstock fed with diet containing 40mg/kg of inorganic zinc. Sperm concentration, volume, and motility duration, as well as hematocrit percentage, were higher in all treatments supplemented with zinc compared to control. Offspring survival up to 1g of weight was significantly higher in fish fed with diet containing inorganic zinc than other treatments (P<0.05). The results of this study showed that zinc supplements would play an important role in improving the capability and functional performance of male rainbow trout.

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