Effect of citric acid and microbial phytase on serum enzyme activities and plasma minerals retention in broiler chicks

An experiment was conducted to study the effect of microbial phytase supplementation and citric acid in broiler chicks fed corn-soybean meal base diets on enzyme activities and some blood parameters of serum and plasma minerals concentration in Ross 308 strain broilers. The data was analysed using a randomized complete block design with factorial arrangement of 3x3, three levels of citric acids (0, 3 and 6%) and three levels of phytase (0, 500 and 1000 enzyme unit per kg). There were three replicates for each treatment that total to 270 chicks for the whole experiment. The results indicated that addition of citric acid to diets caused significant decrease in alkaline phosphatase (P<0.05), lactate dehydrogenase (P<0.01) activities, cholesterol (P<0.05) and plasma phosphorus (P) (P<0.01) and Fe (P<0.05) concentrations. Microbial phytase caused significant decrease (P<0.01) in serum enzyme activities and plasma Fe concentration and significantly increased (P<0.01) aspartate aminotransferase activity, triglyceride and plasma P concentration. Microbial phytase and citric acid could modify some serum enzyme activities and increase the availability and use of minerals for growth and performance improvement of broilers. It is therefore necessary to re-evaluate mineral requirements of broiler chickens when a diet is supplemented with phytase and citric acid.