An experiment was conducted during 7 months to test. the effect of triploidy on growth, sexual maturation, carcass and chemical analysis of O. niloticus. Triploid O. niloticus had heavier and longer bodies than diploids from 3 to 7 months of age, and the differences were not significant only for body length. This trend was also observed for condition factor,. daily gain and specific growth rate. Feed conversion ratios were better for triploids at some studied ages.
In triploid of both sexes, the values of Gonado-somatic indices (GSI) were smaller than diploids with significant differences between the two ploidy groups. But Hepato-somatic indices, (HSI) of triploid O. niloticus males were larger than that of diploid with significant differences between the two groups. However HSI of triploid females were smaller than that of diploid females but the differences were insignificant.
Carcass traits of O. niloticus had the higher percentages of dressing, viscera, by-products and lower percentages of flesh as compared with that obtained from the diploid.
Chemical analysis of flesh indicated that protein, fat and ash percentages in triploid flesh were higher than in diploids, while the opposite trend was obtained with respect to moisture percentages.
Triploid by-products had the higher percentages of fat and ash and lower percentage of crude protein and moisture with significant differences for moisture only.
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