Effects of Various Levels of Dietary Selenium and Arsenic on Chickens

Various levels of selenium and arsenic additions were made to several types of chicken diets to study their effects on growth and reproduction criteria. Three experiments were conducted. The first study involved day-old chicks and terminated at 64 weeks of age. These yearling hens were then used for the second experiments which terminated when the hens were 104 weeks old. The third study was initiated with 20 week old pullets and terminated when they were 52 weeks old. Feeding purified diets resulted in slower chick growth and lower mature body weights of hens. Selenium additions of 2.0 ppm resulted in hens weighing slightly less throughout the production periods. Those fed 8 ppm weighed even less. This weight difference due to 8 ppm Se was not evident when 15 ppm As was added to a corn-soy diet or with 8 ppm As added to the purified diets. Lower levels of selenium additions (0.1, 0.2 and 2.0 ppm) were not detrimental to egg production. In one experiment a significant (