| Abstrakt: |
The nutritional status of broodstock is an important determinant of egg quality and fry viability in fish species. This study investigated the effects of different broodstock diets on egg productivity and quality in rainbow trout (Oncorhynchus mykiss). Rainbow trout broodstocks (average initial weight 731.25±0.39 g) were fed one of three diets for 75 days: two commercial rainbow trout diets with different protein and fat contents (C and F1 groups), and a semi-wet diet composed of a mixture of trout fry feed and fresh horse mackerel (F2 group). At the end of the study, the C group showed the highest specific growth rate and feeding day growth coefficient values. There were no significant differences in absolute and relative egg production between the dietary groups (p>0.05). However, diet did impact egg nutritional composition and color. The C group eggs had higher levels of omeg-3 and omeg-9 fatty acids, while omeg-6 fatty acids were highest in the F1 group eggs. Total amino acid content, including aromatic, branched-chain and essential amino acids, was highest in the F2 group eggs. The C group eggs also displayed greater chroma, yellowness, and redness compared to the F1 and F2 eggs (p<0.05). In summary, while egg output was similar between rainbow trout broodstock dietary groups, the amino acid profiles and lipid profiles of the eggs differed by diet. Specifically, the Ʃomega-3 PUFA, DHA and Ʃomega-3/Ʃomega-6 ratios in feeds impacted measures of egg quality like color and nutritional value. These findings highlight the importance of broodstock nutrition in determining the composition and quality of rainbow trout eggs. [ABSTRACT FROM AUTHOR] |
