The relationship between iodine in the drinking water and variously processed soybean meal in the diet on the performance of broiler chickens

Abstract

This study has investigated the relationship between iodine when added to the drinking water and variously processed soybean meals on body weight and feed conversion in broiler chicks. Two experiments were conducted with a total 440 one day-old commercial broiler chicks each reared in battery cages. The chicks were fed diets containing 21.58 percent protein and 3212 kcal metabolizable energy (ME) per kg of feed. The results demonstrated that six-week body weight and feed conversion were significantly affected by the test diets. Birds fed diets containing ground raw soybean meal processed for 30 minutes at 100 C or 121 C had suppressed body weights and yielded poor feed conversion. The birds appeared to adjust partially to the raw soybean meal after the third week.Urease activity in the diets was directly related to the cooking time and not necessarily to the cooking temperature. Body weight and feed conversion improved when the urease activity in the diet was low. The addition of 2 ppm of iodine to the drinking water yielded a consistently positive response in both body weight and feed conversion. Birds fed the processed ground raw soybean meal produced the largest growth response with the use of iodine in the drinking water. ...