Die Bodenkultur - Journal for Land Management, Food and Environment
S. Bickel, W. Wetscherek and R. Leitgeb:
Influence of fat source on the performance of broilers, and on relevant carcass characteristics for consumers
1st Report: Influence of rapeseed oil and animal fat on growing and slaughtering performance of broilers
Rapeseed oil and animal fat were compared in broiler diets consisting of 59,4 % corn, 30 % soybean meal, 3 % corn gluten, 3,7 % mineral and vitamin premix and 3,9 % added fat. In the four experimental groups 3,9 % animal fat were gradually substituted by rapeseed oil in steps of 1,3 %. Each experimental group consisted of 45 day old broiler chicks which were arranged in 3 replicates (3 pens) with 15 chicks each.
The inclusion of rapeseed oil reduced the body weight gain of the broilers. Feed conversion was between 1,85 and 1,88. Body weight at slaughter was 1873, 1750, 1720 and 1730 g for groups with 0, 1,3, 2,6 and 3,9 % of rapeseed oil, respectively. The lower daily weight gain of the groups with more than 1,3 % rapeseed oil is a result of a lowered feed consumption. The relative carcass yield was not influenced by the different dietary fat sources.
The fatty acid composition of the carcass was significantly influenced by the dietary fat. The saturated fatty acides decreased and the unsaturated fatty acides increased by the substitution of animal fat by rape seed oil.
It is concluded that the substitution of animal fat by rapeseed oil in broiler diets reduces growth performance. On the other hand, the content of polyunsaturated fatty acids of meat protions is changed in a direction desirable for the consumers.
Key words: broiler, fattening performance, carcass, rapeseed oil, fatty acids.