The effects of sorghum tannin and protein level on the performance of laying hens maintained in two temperature environments.

A study was conducted to investigate the effect of sorghum grain tannins on the performance of laying hens. A total of 144 White Leghorn hens were arrayed according to egg production during a 10-day preexperimental period into eight groups consisting of four nutritional treatments in each of two constant temperature environments (22 and 28 C). The nutritional treatments consisted of low (RS610) and high (Savanna) tannin sorghum grains compared isonitrogenously within a protein level at two protein levels (11.5 and 14.5%) in sorghum-soybean meal diets. These diets were fed for an experimental period of 6 weeks. Egg production and feed efficiency were reduced and weight loss was increased by 11.5% protein as compared with 14.5% protein. Tannin significantly reduced egg production and feed efficiency at both protein levels while egg specific gravity and shell thickness were adversely affected only at the lower level of protein. Egg weight and weight loss of hens were not affected by tannin. Except for weight loss, all parameters were slightly reduced by the higher temperature. At the end of the experiment, all hens were placed on a commercial laying ration for a 31-day period. Recovery from the treatment effects was evidenced by the similar egg production, body weight, egg weight, and shell characteristics among the previous treatments at the end of this period.