COX-1 and COX-2 expression in ovaries of control and fish oil-fed hens. (A & B) The hens treated with 100 mg/kg (n=6) and 175 mg/kg (n=8) fish oil had significantly lower COX-1 protein and mRNA expression compared to ovaries of control hens (n=8; P<0.01). (C & D) A significant reduction in expression of COX-2 protein and mRNA was seen in ovaries of hens treated with 100 mg/kg fish oil (n=6) compared to control hens (n=8; P<0.05). The ovaries of hens fed 175 mg/kg fish oil (n=8) had the lowest COX-2 protein expression among groups which was significantly lower than control hens (n=8; P<0.01). There was a significant decrease in COX-2 mRNA expression in ovaries of chickens treated with 175 mg/kg (n=8) fish oil in comparison to control hens (n=8; P<0.05). *, P<0.05; **, P<0.01. Bars indicate standard error.