摘要This study aimed to examine the impact of dietary carbohydrate to lipid(CHO/L)ratio on the growth,reproductive,and offspring performance of broodstock yellow catfish,and to elucidate the metabolic differences between mothers and offspring using lipidomics.Five isonitrogenous and isoenergetic diets with varying CHO/L ratios(0.65,1.44,2.11,3.13,and 5.36)were fed to five groups of female broodfish with three replicates per group and 35 female broodfish per replocate in a pond-cage culture system.After an eight-week feeding trial,the dietary CHO/L ratio had a significant impact on the growth and reproductive performance of female yellow catfish.The weight gain ratio(WGR)and specific growth rate(SGR)in the CHO/L0.65 and CHO/L2.11 groups were significantly higher than those in the CHO/L5.36 group(P＜0.05).The fertilization and hatching rates were the highest when the dietary CHO/L ratio was 0.65 and 2.11,respectively.When the dietary CHO/L ratio was 3.13 and 5.36,the plasma contents of testosterone(T)was significantly lower than those of other groups(P=0.013),and the plasma vitel-logenin(VTG)content was the lowest when the CHO/L ratio was 5.36.The plasma contents of estradiol(E2)significantly decreased with increasing dietary CHO/L ratio(PL=0.012).Lipidomic analysis revealed that the ovary primarily consisted of five subclasses in terms of lipid composition,namely triglyceride,fatty acyl,sterol,glycerophospholipid,and sphingolipid;however,sphingolipids were not detected in the larvae.The relative expression levels of the ovarian lipid metabolism-related genes sterol regulatory element binding protein 1(srebp1),acetyl-CoA carboxylase(acc),delta(12)-oleate desaturase(fad2),and elongation of very long chain fatty acids protein 5(elvol5)significantly increased with increasing dietary CHO/L ratio(P＜0.05).The relative expression levels of lipid metabolism-related genes srebp 1,perox-isome proliferator activated receptor α(pparα),carnitine palmitoyl transferase 1 isoform(cpt),adipose triglyceride lipase(atgl),fad2,and elvol5 in offspring larvae were initially increased and then decreased with increasing dietary CHO/L ratios until reaching a maximum at a ratio of 2.11(P＜0.05).In conclusion,based on the broken-line regression of the dietary CHO/L ratio and egg diameter,the optimal dietary CHO/L ratio was 1.91 for broodfish yellow catfish.A high CHO/L ratio diet results in increased lipogenesis and hepatic lipid accumulation in maternal organisms,leading to impaired reproductive performance and reduced offspring quality.