effects of medicinal plant, prebiotic, probiotic and antibiotic on intestinal morphology and nutrient digestibility of broilers chickens

this study was carried out to investigate the effects of medicinal plants, prebiotic and probiotic as alternatives to antibiotics on the growth performance, intestinal morphology and ileal digestibility of nutrients in broilers. a total of 288 one- day-old broiler chicks (cobb 500) were randomly assigned to 6 treatments and 4 replicates with 12 chicks per each replicate in a completely randomize design for 6 weeks. treatments include diet 1 was a negative control containing no antibiotics or growth promoters (nc). diet 2 was the positive control consisting of nc plus virginiamycin (antibiotic). diet 3 was nc and digestarom (blend of medicinal plants). diet 4 was nc to which protexin (probiotic) was added. diet 5 was nc plus immunowall (prebiotic). diet 6 was nc plus a combination of immunowall and protexin. the mortality rate and survival percentage were determined daily. body weight gain, feed intake and feed conversion ratio (fcr) were measured weekly. nutrients digestibility was determined in d 42.  in order to evaluate intestinal morphology, at d 38 day of age, one bird from each replicate was killed by cervical dislocation. body weight gain, feed intake, mortality rate, nutrient digestibility and crypt depths of the duodenum and jejunum and villus height/crypt depth ratio of the three intestinal segment were unaffected by dietary supplementation of experimental treatments. chicks supplemented with antibiotic had shorter villus height and crypt depth in the jejunum than birds fed probiotic and prebiotic. the results demonstrated that addition of the prebiotic to the feed as well as antibiotic had a significant effect on fcr at 42 days of age.