Effect of dietary levels of a modified meat meal on performance and small intestinal morphology of broiler chickens

A locally produced meat meal in Ardabil province in Iran is mixed with 150 g wheat bran, 100 g feather meal and 150 g zeolite per kg. Experimentally, this leads to an improvement in physical texture and preservation characteristics. In this experiment, six hundred 3-week-old Cobb 500 broiler chicks of both sexes were assigned randomly to 24 floor pens with 25 chicks in each pen. Dietary modified meat meal at six inclusions levels of 0 (control diet containing 50 g/kg fish meal), 20, 35, 50, 65 or 80 g/kg, created the treatments of a completely randomized design to survey analysis the performance traits. For histological data, a completely randomized design with a 2 x 6 factorial arrangement was used. The experimental factors were bird sex at 2 levels and dietary modified meat meal at the corresponding levels noted above. The experiment was carried out at 21 to 42 days of age. Dietary modified meat meal did not affect on birds' feed intake and body weight gain, but feed conversion ratio improved in the birds fed diet with 20 g modified meat meal/kg in comparison to the control. Compared to the control, the birds fed 20, 35 and 50 g of modified meat meal/kg diet had a significantly lower villus height, crypt depth and crypt depth to villi height ratio, increased goblet cell number and higher epithelium thickness in duodenum. However, these values significantly altered after feeding of 65 and 80 g of modified meat meal/kg diet and showed an almost similar value to control. The same condition observed in jejunum section, with the exception of the goblet cell number that was not affected by dietary alteration. Ileal histological morphology was not influenced by dietary manipulation. The only significant effect of sex was the higher jejunal epithelial thickness in females compared with males. The results of this study demonstrate that the inclusion of modified meat meal up to 80 g/kg of broiler diets resulted in comparable small intestinal morphometric characteristics to a common commercial fish meal based diet. It seems that the processed meat meal can be used as a suitable alternative to dietary fish meal in broiler chickens diets.