46-9 Sat Jan 2 Maternal diet affects utilization of endogenous lipids by red drum embryos and early larvae Hou, Z*; Fuiman, LA; University of Texas at Austin, Marine Science Institute, Port Aransas, TX; University of Texas at Austin, Marine Science Institute, Port Aransas, TX zhenxin.hou@utexas.edu
Embryonic and early larval development and metabolism are fueled entirely by maternally derived nutritional resources (yolk and oil) before the onset of exogenous feeding. Composition of those resources depends, in part, on maternal diet. To examine the effects of maternal diet on the utilization of endogenous lipids and fatty acids, we fed red drum (Sciaenops ocellatus) broodstock four different diets. We sampled embryos and unfed larvae every 12 hours from 12 hours post-fertilization (hpf) until starvation (96-120 hpf) (n = 5 spawns). Differences in maternal diets did not affect egg total lipid content but resulted in distinctive egg fatty acid compositions (at 12 hpf). Rates of utilization of the oil globule between 36 and 84 hpf were significantly affected by the maternal diet, resulting in a significantly different mean oil globule size at the first feeding stage (84 hpf). Consumption rates for 14 fatty acids were significantly different among diet treatments and were proportional to their initial concentration (measured at 12 hpf). As a result, differences in fatty acid compositions associated with maternal diet diminished over time, but fatty acid profiles remained different even at later stages. In addition, egg lipid content was positively correlated with larval standard length 84 hpf (R2 = 0.40). This study suggests that maternal diet could affect energy metabolism and larval tissue composition through its effect on yolk composition. These effects could have consequences for the survival and critical physiological functions of fish larvae during the critical period of transition to exogenous feeding.