Effects of ascorbic acid and lighting schedule on tibiotarsus strength and bone characteristics in broilers

Abstract

Abstract. This study was conducted to determine the effects of two lighting programs (continuous program; 24 h lighting or intermittent; 12 h daylight followed by three cycles of 1 h lighting and 3 h dark program during the night period) and three different ascorbic acid (AA) supplementations (0, 200 and 400 mg/l, added to water) on some serum parameters, ash content and mechanical properties of tibiotarsus. For this purpose one-day-old male commercial (Ross PM3) broiler chicks (n=600) were divided into 6 treatment groups (2×3) with random replicates (4 replicates per treatment). At the end of 6 weeks, intermittent lighting program negatively influenced serum alkaline phosphatase (ALP) and calcium (Ca) levels (P<0.001) while continuous lighting program had positive influence on bone ash, Ca and phosphorus (P) content (P<0.001). The AA addition decreased serum inorganic phosphorus (Pi) level and positively affected bone chemical characteristics (P<0.001). On the mid-section of the bone, although intermittent lighting had positive effect on bone mechanical parameters (P<0.001), no remarkable effect was observed by AA supplementation. The results of the present study suggest that interaction of intermittent lighting and AA supplementation (200 mg/ l) may have positive effect on chemical composition and mechanical characteristics of bone in broilers.