EN
The observations were done on 45 broilers at the age of 2—4 months. Using the method of perfused intestinal loop vivo, the absorption of vitamin C from jejunum and coecum at the presence of volatile fatty acids: acetic, propionic and butyric and separately butyric was determined. Ascorbic acid was determined by the method of Roe-Kuethner. It was found that the three basal volatile fatty acids and butyric acid alone decreased absorption of vitamin C and that this decrease depended upon the concentration of volatile fatty acids. Increased concentration of the acids lowered the rate of vitamin C absorption. Volatile fatty acids at a concentration of 50 mM/L lowered absorption of vitamic C in jejunum up to 80,8% (from 2.6 to 2.1 mg/L/cm²/60 min.) and in coecum up to 87.8% (from 4.1 to 3.6 mg/L/cm²/60 min.). Higher concentrations of volatile fatty acids as 130 mM/L lowered absorption of vitamic C more intensively up to 65.4% in jejunum (from 2.6 to 1.7 mg/L/cm²/60 min.) and in coecum up to 68.3% (from 4.1 to 2.8 mg/L/cm²/60 min.). The most active appeared to be propionic acid then butyric and acetic acid. Food of a high content of carbohydrates produces volatile fatty acids in the alimentary tract of poultry decreasing absorption of vitamin C. Therefore enrichment of food with vitamin C or application of vitamin C in poultry is necessary.