RESUMO
The aim of the present study was to investigate the in vivo anti-metastatic activity of the red pigments of red yolk eggs laid by the ducks dieting on Potamogeton cripus L on the mammary carcinoma (4T1). The pigments were extracted with petroleum ether and acetone (2:1, v/v). BALB/c mice were divided into three groups (n=6), fed with the extracts at 150 mg/kg body weight (BW)/day (DEYE-H) or at 50 mg/kg BW/day (DEYE-L) and identical buffer without the extract (control group). The extracts were administered for 34 days. The treatment significantly inhibited the growth of orthotopical 4T1 tumour (DEYE-H vs control, 1:2; DEYE-L vs control, 2:3) and reduced the metastasis of tumour in the lungs (DEYE-H vs control, 4:7; DEYE-L vs control, 5:7), without statistical difference of body weight among the three groups.