Comparison of broiler live performance, carcass characteristics, and fatty acid composition of thigh meat when fed diets supplemented with neutralized sunflower soapstock or soybean oil 1

SUMMARY Two experiments were conducted to determine the influence of adding neutralized sunflower soapstock (NSS) or soybean oil (SO) to the broiler diet. In experiment 1, one hundred five 15-d-old Ross 308 broiler chickens were used to evaluate the AMEn of NSS by the difference method. In experiment 2, a completely randomized design was used to evaluate the effects of fat source and level on broiler live performance, carcass characteristics, and fatty acid composition of thigh meat. A 2 × 3 factorial arrangement with 2 types of fat (NSS and SO) at 3 levels of inclusion (2, 4, and 6%) was used with 5 replicates per treatment using total of 750 birds. The average AMEn of the NSS was determined as 8,530 kcal/kg. Performance of birds was unaffected by the dietary fat sources. Increasing the fat level from 2 to 6% improved the overall BW gain (P < 0.0001) and FCR (P < 0.001) of broilers, whereas feed intake was unaffected by different fat levels. Hot carcass yield and rib cage weight were higher for SO-fed birds than NSS-fed birds (P < 0.05). Wings and rib cage weights were higher in birds fed the 6% fat diet (P < 0.05). Leg quarter yield decreased with increased levels of fat inclusion (P < 0.01), whereas breast yield increased (P < 0.05). Dietary fat type modified fatty acids of thigh meat, resulting in significantly higher content of C14:0, C16:0, C16:1, C18:1, sum of saturated fatty acids, and sum of monounsaturated fatty acids in birds fed NSS diets, whereas C18:2, C18:3, C20:0, and sum of polyunsaturated fatty acid contents decreased with NSS inclusion (P < 0.05). Saturated fatty acids and monounsaturated fatty acids significantly decreased and polyunsaturated fatty acids increased when dietary fat level increased (P < 0.0001). In conclusion, NSS can be included in broiler diets without any major differences in live performance by modifying the fatty acid profile of meat.