KAFKAS UNIVERSITESI VETERINER FAKULTESI DERGISI, cilt.21, sa.5, ss.729-737, 2015 (SCI-Expanded)
The effect of clinoptilolite alone or in combination with phytase on the performance, carcass characteristics, intestinal histomorphology, and tibia ash and Ca, P levels were determined in male broiler chickens. Total of 192 one-day-old male broiler chicks (Ross 308) were randomly assigned to 4 different treatments with 8 replicates containing 6 birds each. Treatment 1 (T1) was served as control fed a diet without clinoptilolite and/or phytase, Treatment 2 (T2) was supplemented with 2% clinoptilolite. Treatment 3 (T3) and Treatment 4 (T4) were (formulated Ca; 0.87, 0.80 and 0.75%, available P; 0.30, 0.28 and 0.26% for starter, grower, and finisher periods respectively) supplemented 0.01% phytase and 2% clinoptilolite + 0.01% phytase, respectively. The results showed that combined use of clinoptilolite and phytase (T4) in broiler diets decreased (P = 0.044) body weight gain at 1-14 d. Dietary treatments had no effect on body weight gain, feed intake (FI) and feed conversion ratio (FCR) during the entire experimental period. Supplementation with phytase (T3) significantly (P = 0.006) decreased crypt depth in duodenum on d 21. Tibia ash and phosphorus level were decreased due to combined use of clinoptilolite and phytase (T4) in comparison to those fed control (T1) and clinoptilolite (T2) diets on d 21. At 42 days of age, tibia ash, Ca, P levels and Ca/P ratio was not changed by the treatments. It is concluded that there might be a positive effect of 2% clinoptilolite on the performance of male broilers after starting period.