Effects of inclusion of full-fat sunflower kernels and hulls in diets for growing broiler chickens

Two experiments were conducted to determine the effect of feeding full-fat sunflower kernels (FFSK; 0, 50, 100 and 150 g kg−1) and sunflower hulls (SH; 0, 17, 33 and 50 g kg−1) in diets for broiler chickens. In both experiments, 224 one-day old birds were distributed randomly to 28 lots of eight animals each. In the first experiment, the addition of up to 150 g kg−1 FFSK yielded a significant reduction (12 and 10% respectively; P < 0.05) in weight gain and feed consumption. No significant differences were detected in relation with feed to gain ratio and relative weight of gizzard, pancreas and abdominal fat. There was, however, a significant increase (15, 13, 15 and 16% respectively; P < 0.05) in relative liver weight and relative length of duodenum, jejunum, ileum and caeca in chicks fed with increased concentrations of FFSK in the diets, compared with those fed the wheat-soybean diet. Ileal digestibility of protein, trypsin and amylase digesta activities were not affected. Digestibility of fat and digesta lipase activity were reduced and increased respectively (8 and 60%; P < 0.05) in those birds fed the highest level of addition of FFSK. In the second experiment, different concentrations of SH (0, 17, 33 and 50 g kg−1) were used. The performance, relative weight of gizzard, liver, pancreas and abdominal fat, relative length of duodenum, jejunum and caeca were not significantly affected by the addition of SH. The results indicated that the growth data and fat digestibility of the birds were adversely affected by the addition of full-fat sunflower kernels of up to 50 g kg−1. However, the SH at levels of up to 50 g kg−1 had no adverse effect on the general performance of broiler chickens.