Abstract: Fatty acid composition and content were analyzed in juvenile(0+ age) American shad Alosa sapidissima cultured in a 0.17 hm2 and 1.5 m depth shaded pond during different growth stages(July-November) by biochemical analysis methods to understand the lipid nutrition status and the changes in fatty acid composition. The moisture of American shad was shown to be significantly decreased with the growth(P<0.05), the total lipid contents being increased significantly from 12.93% in July to 35.05% in November with the growth(P<0.05). There were 8 saturated fatty acids(SFA), 7 mono-unsaturated fatty acids(MUFA), and 11 polyunsaturated fatty acids(PUFA) in the dry samples of American shad in different growth stages(July-November). The maximal C18:1 n9 c(27.11%-36.87%) was observed in 0+ age American shad juvenile(July-November), and the percent content of C16:0(19.63%-25.33%) and C18:0(6.42%-7.46%) was decreased significantly with the growth of the fish. The C18:2 n6 c content(16.87%-22.95%) was increased first and then decreased with the growth, with the maximum(22.95%) in September, indicating that fatty acid composition of 0+ age juvenile is closely related to the composition of the diet. However, low levels of C16:0 and C18:0 in the diet led to a sustained decline in the levels of C16:0 and C18:0 in the 0+ age juveniles. The diet containing low C18:1 n9 c(23.93%-24.04%) did not cause the decrease in C18:1 n9 c content in the juvenile. On the contrary, the C18:1 n9 c content in the juveniles was increased significantly from 27.11% in August to 36.87% in November, showing a negative correlation;high C18:2 n6 c content(45.52%-46.88%) in the diet did not result in enrichment of C18:2 n6 c (16.87%-22.95%). Lower levels of DHA(1.57%-1.79%) in diet resulted in a significant decline in the DHA in the juveniles, from 4.00% in August to 1.62% in November. The diet containing low ∑n-3 PUFA/∑n-6 PUFA ratio(0.13-0.14) also significantly affected the variation in ∑n-3 PUFA/∑n-6 PUFA ratio in fish, with the ratio from 0.29 in
2019, Vol. 34 
