The effects of feeding with zinc enriched yeast (Saccharomyces cerevisiae) on growth and carcass quality of rainbow trout(Oncorhynchus mykiss)
Subject Areas : Veterinary Clinical Pathology
1 - Assistant Professor, Department of Veterinary Medicine, Maku Branch, Islamic Azad University, Maku, Iran.
Keywords: Growth factors, Rainbow trout, Saccharomyces cerevisiae, Zinc,
Abstract :
The United Nations’ sustainable development goals recognize food security and nutrition as a priority of the global development program, and fish plays an important role in providing global food. Therefore, this study aimed to investigate the possibility of using enriched yeast to improve the growth indicators and quality of rainbow trout carcasses. In this research, rainbow trout samples were fed with four different levels of yeast enriched with zinc: concentrations of 0, 1 × 106, 1 × 107, and 1 × 108 CFU/g for 75 days in three replicates. For the first 60 days, the fish were fed with yeast enriched with zinc, and for the remaining 15 days, they were fed only with the food of the control group. The growth factors, carcass quality, and zinc levels in serum, muscle, and liver of fish were measured. The results showed that the fish fed with zinc-enriched yeast at a concentration of 1 × 107 CFU/g had the highest final weight (106.67 ± 8.4 g) and final length (20.45 ± 2.28 cm). Additionally, the growth rate, specific growth rate, and condition factor in fish fed with different concentrations of zinc-enriched yeast were significantly higher than in the control group (p<0.05). The amount of muscle fat was lower in the control group, but they had more liver fat than the other groups. The amount of zinc in the serum was significantly higher than the amount in the liver and muscle tissues. In conclusion, supplementing the diet of rainbow trout with enriched yeast with zinc can significantly improve growth indicators and carcass quality.
