Effect of Supplementation of Drinking Water with Different Levels of Boron on Performance and Immune Organ Parameters of Broilers

Abstract

This study was performed to investigate changes in growth performance, immune organs weight and microstructure of broilers fed different levels of boron (0, 100, 200 and 400 mg/L) in drinking water for 6 weeks. A total of 240 newly-hatched Gushi chickens [body weight (BW)=34±2 kg; male: female=1:1] were equally divided into 4 treatments with 5 pens each (n=12 per pen). The birds were weighed after fasting for 12 h every two weeks until the end of experiment. The thymus, bursa and spleen samples were collected every two weeks and fixed in 4% paraformaldehyde phosphate buffer at room temperature (25°C). Results showed that BW and average daily gain significantly reduced by addition of 200 and 400 mg/L boron to drinking water compared to control group (P200 mg/L) could significantly inhibit the growth of immune organs and even exhibit toxic effects.