Besides the food and feed use the oil from rapeseed
(Brassica napus) is also the basis for European
biodiesel production. Therefore rapeseed meal and
rapeseed cake are increasingly available as protein
and energy feed components. Whereas the meal
from ‘‘00-rapeseed’’ causes no problems in the feeding
of ruminants, there is a maximum of 10 %
rapeseed meal and 5 % rapeseed cake in the feed for
hen strains laying white eggs (Spiekers et al. 2012;
Jeroch and Da¨nicke 2012). For some brown-egg laying
hen strains (Honkatukia et al. 2005), the inability to
metabolize trimethylamin (TMA) originating from
the bacterial degradation of rapeseed sinapine in
the large intestine results in ‘‘fishy taint’’ eggs, and
therefore rapeseed feeds are seen critically (Butler
and Fenwick 1984). Meanwhile the Lohmann Tierzucht
Company identified the gene which is
responsible for the inability of some hens to metabolize
TMA and these hens were eliminated from
breeding. So, Lohmann Tierzucht announced that all
commercial laying hens of Lohmann and H&N origin
hatching from January 2007 onwards are free of the
genetic defect and may receive diets containing rape
seed products (Pottgu¨ter 2006).