To determine the response of Pacific white shrimp Litopenaeus vannamei to different levels of dietary
choline, juvenile white shrimp (1.75 ± 0.09 g) were fed six semi-purified diets supplemented with 0 (control), 2000, 4000, 6000, 8000, and 12,000 mg/kg
choline chloride for eight weeks. Growth performance, whole-body composition, serum characteristics and hepatopancreatic
antioxidant indexes were evaluated. Meanwhile, serum metabolome and hepatopancreas transcriptome were performed to examine the overall difference in metabolite and gene expression. The
weight gain, survival, specific growth rate, condition factor and hepatosomatic index were not affected by dietary
choline levels. The shrimp fed 6000 mg/kg dietary
choline chloride gained the maximal whole-body crude
protein, which was significantly higher than that of shrimp fed with 12,000 mg/kg dietary
choline. Serum total
cholesterol of shrimp fed 6000 mg/kg dietary
choline was higher than that in shrimp fed 4000 mg/kg
choline. Dietary
choline significantly decreased
malondialdehyde content,
superoxide dismutase, and
glutathione peroxidase activities in shrimp hepatopancreas. Compared with the shrimp fed 6000 mg/kg dietary
choline chloride, the
glycerophospholipid metabolism pathway was significantly enriched in the shrimp fed 0 mg/kg dietary
choline chloride, and the
choline content and
bile salt-activated
lipase-like expression were upregulated. The expression of trypsin-1-like in protein digestion and absorption pathway was significantly downregulated in the shrimp fed 12,000 mg/kg dietary
choline chloride.
Apolipoprotein D might be a potential
biomarker in shrimp, and dietary
choline played an important role in lipid metabolism, especially in the reduction of oxidative damage in L. vannamei. Based on the results of
weight gain and degree of oxidative damage, 1082 mg/kg dietary
choline could meet the growth requirement of L. vannamei, but 2822 mg/kg dietary
choline was needed to reduce peroxidation damage.