MINIMIZING THE EFFECTS OF DIETARY ANIMAL FAT ON PRODUCT QUALITY IN BROILER CHICKS AND MUSKOVY DUCKS BY REGARDING THE RELATION OF LINOLEIC-ACID TO ENERGY

In two experiments, 12 male broiler chicks and 40 Muskovy ducks were f ed with diets supplement by bone fat at fairly constant relations of l inoleic acid to apparent metabolizable energy (AME). The effects on ca rcass, meat and fat tissue quality were investigated. In both, broiler s and ducks bone fat had no significant effect on carcass weight as we ll as on the percentage of breast, thigh and abdominal fat. Also meat quality, as assessed by cooking loss in breast and thigh as well as br east shear values, was not affected by bone fat. The broiler had a rel ation of linoleic acid (g) to AME (MJ) of 2.21 and 2.73 without and wi th bone fat, respectively. In the diets of the Muskovy ducks the respe ctive values were 1.37 and 1.23. As in poultry feed intake is closely related to dietary energy concentration, the use of bone fat presumabl y led to a higher linoleic acid intake in the broilers and to a lower one in the ducks; Fat tissue characteristics as described by melting p oint, oxidative stability and pattern of fatty acids, reflect the diff erences in the presumable intake of linoleic acid. Consequently, bone fat resulted in a higher content of polyenic acids and a lower oxidati ve stability in the broilers according to the difference in the relati on of linoleic acid to AME. In the ducks, only small effects on fatty acid pattern of abdominal fat occurred because of the only slight diff erences in the relation of linoleic acid to AME. These results indicat e that diets can be evaluated more precisely with respect to the effec ts on product quality in broilers and ducks using the relation of lino leic acid to AME than using only fat content and fatty acid pattern of feed, respectively.