A study was carried out to investigate the effects of dietary supplementation of an organic acids mixture and two methionine supplements on intestinal morphology, protein and nucleic acids content, microbial population and performance of broiler chickens. Six hundred unsexed day-old Ross 308 broiler chicks were used in a factorial arrangement (3 × 2) based on a completely randomised design by four replicates with 25 chicks in each. Experimental diets consisted of: 0% organic acid mixture + DL-methionine (Treatment 1), 0% organic acid mixture + Alimet (Treatment 2), 0.5% organic acid mixture + DL-methionine (Treatment 3), 0.5% organic acid mixture + Alimet (Treatment 4), 1% organic acid mixture + DL-methionine (Treatment 5) and 1% organic acid mixture + Alimet (Treatment 6). A significant increase in jejunum mucosal DNA content was found by using 1% of organic acid mixture compared with those by other levels of organic acids at 21 days of age (P < 0.05). Also Treatments 5 and 6 had a higher mucosal DNA content than other treatments (P < 0.05) in a similar period. While at grower stage, the results have shown that protein content, protein/DNA and protein/RNA ratio by 0.5 and 1% of organic acids mixture significantly increased compared with those in the 0% level (P < 0.05). The addition of 1% level of organic acid mixture significantly increased villus height compared with 0 and 0.5% level of organic acid mixture at 21 days of age (P < 0.05). Highest and lowest villus heights were obtained by Treatments 1 and 6 (P < 0.05). Crypt depth increased by 0.5 and 1% of organic acid at 21 and 42 days of age (P < 0.05). Villus surface was significantly increased by 1% of organic acid mixture compared with that by 0% level at 21 days of age. The use of organic acid levels especially 1% resulted in an increase in lactic acid bacteria and decreased Enterobacteriaceae counts in the ileum of broiler chicken (P < 0.05). Better bodyweight and feed conversion ratio were obtained (P < 0.05) by 0.5 and 1% of organic acids mixture, although no response was found in feed intake and mortality in this respect (P > 0.05). The results of this study have shown improved reactions on intestinal morphometrical parameters and microflora atmosphors, by using 1% organic acid mixture. In contrast no differences were found between Alimet and DL-methionine in all tested parameters.

This study was carried out to investigate the effects of dietary supplementation of hydroalcoholic extract of Heracleum Persicum fruit (HPE) on performance, immune responses, small intestine morphology, haematological parameters and carcass characteristics of broiler chickens. A total of 300 day-old Ross 308 broiler chicks were used in a completely randomized design with five treatments and five replicates of 12 chicks each. The treatments were comprised of a corn-soybean meal base diet supplemented with five levels of HPE at 0(control), 100, 200, 300 and 400 mg/kg diet. Average daily feed intake (ADFI) was increased by 100 mg/kg of HPE comparing to control group during 11-24 d (p < 0.05). HPE at the levels of 200, 300 and 400 mg/kg, decreased (p < 0.05) serum cholesterol comparing to control group and showed a linear response to different levels of HPE (p = 0.0007). Also, LDL was decreased by 300 mg/kg of HPE (p < 0.05). The villus height to crypt depth ratio (VH/CD) was increased by 400 mg/kg of HPE, comparing to control group at 42 d (p < 0.05). Also, this ratio showed a linear response to different levels of HPE (p = 0.007). The results of this study indicated that HPE improves performance and intestine morphometrical and haematological parameters of broiler chickens. ARTICLE HISTORY