Intestinal DNA concentration and protein synthesis in response to low quality diets in two strains of Leghorn layers
Performance, protein synthesis and mucosal DNA in small intestine of Leghorn hens may be affected by low quality feedstuff. An experiment was conducted in completely randomized design (CRD) in 2 × 2 factorial arrangement. Main factors included diets containing 20 and 40 % barley and black and blue strains of leghorn. Layer performance was recorded weekly up to eight weeks. Egg production (%), egg mass and egg number were significantly higher in black strain leghorn on 20% barley diet than blue strain with 40% barley diet (P<0.05). Treatments blue × 40% barley and black × 20% barley showed lowest and highest egg production percentage, egg mass and egg number, respectively (P<0.05). The lowest protein synthesis in small intestine was shown in blue × 40% barley treatment group. Small intestine mucosal DNA quantity in blue strain was significantly higher than that in black strain (P<0.05). In contrast, protein synthesis in blue strain was lower than that in black strain (P<0.05). It was concluded that lower performance in blue × 40% treatment group could be related to lower protein synthesis in small intestine in blue strain, and this may be due to the high barley (40%) contained in diet.
Key words: Performance, protein synthesis, mucosal DNA, small intestine.