The effect of acidified soapstocks on feed conversion and broiler skin pigmentation

The effect of different soapstocks (corn, sunflower, canola, and soybean) on productive performance and skin broiler pigmentation was investigated. Soapstock was added to reach 1.0% polyunsaturated fatty acids in the diet. The addition of soybean soapstock significantly improved live body weight gain of the birds from 1 to 7 wk of age. A live body weight gain of 1,736 g/bird was calculated for broilers fed with the soybean soapstock diet. Feed conversion was significantly higher for broilers fed with the soybean soapstock diet, and no negative effect was observed. Compared to broilers fed with Pixtafil (100.0% pigmentation), those fed soybean soapstock (when added as a supplement of 1.0% polyunsaturated fatty acids in the diet) reached 48.0% pigmentation, and those fed corn soapstock reached only 7.3%. When the diets were complemented with Pixtafil to reach 100% of calculated pigmentation, the soybean soapstock diet reached 100.8% pigmentation compared to a canola soapstock diet that reached 72.0% pigmentation. Acidified soybean soapstock could be a source of polyunsaturated fatty acids and of xantophyl pigments in broiler feeding.