• feed utilization;
  • growth;
  • methionine;
  • plant protein;
  • shrimp


An eight-week feeding experiment was conducted to investigate the effects of dietary crystalline methionine (CMet) or oligo-methionine (OMet) on growth performance and feed utilization of white shrimp, Litopenaeus vannamei. A practical diet was used as control diet. The other four diets replacing 30% and 60% fish meal by plant meal were formulated. To balance the methionine content, 1 g kg−1 CMet (SPP30-CMet) or OMet (SPP30-OMet) was added in 30% fish meal replacing diets, and 2 g kg−1 CMet (SPP60-CMet) or OMet (SPP60-OMet) was added in 60% fish meal replacing diets. Results showed that methionine source significantly affected growth, body compositions and hepatosomatic indices (HSI) of white shrimp (< 0.05). Shrimps in SPP60-CMet treatment showed significantly lower weight gain, body crude protein content and higher HSI than those in the control (< 0.05). However, no significant difference in these indices was observed between the control and OMet supplemented treatments (> 0.05). Shrimps in SPP30-OMet treatment showed significantly higher feed efficiency ratio and protein efficiency ratio than those in SPP30-CMet treatment (< 0.05). This study indicated that compared with the CMet, dietary OMet resulted in better growth and feed efficiency of L. vannamei fed with plant protein-enriched diets.