Crambe cake impairs lamb performance and fatty acid profile of meat

The replacement of diet soybean meal protein with crambe cake protein (0%, 22%, 44% and 66%) was investigated to evaluate the effect on lamb performance and meat quality, as well as the extent to which erucic acid was incorporated into the meat. The inclusion of increasing levels of crambe cake resulted in poorer lamb performance, as demonstrated by a linear decrease in final liveweight and carcass weight. There was also an increase in plasma blood concentrations of aspartate transaminase and alanine transaminase, indicating hepatic injury. Reduced ether extract concentration of meat was observed, leading to higher shear-force values and a linear decrease in meat luminosity. The fatty acid profile of meat was drastically modified, presenting a reduction in total saturated and polyunsaturated fatty acid concentrations, particularly in the concentration of α-linoleic acid. Additionally, the total monounsaturated fatty acid concentration in meat decreased, while the concentration of erucic acid increased from 0.11% of total fatty acids in Longissimus lumborum samples from lambs fed diets with no inclusion of crambe cake, to 3.70%, 5.82% and 8.04% of total fatty acids in those from lambs fed diets where 22%, 44% and 66%, respectively, of the soybean meal protein was replaced with crambe cake protein. Therefore, the concentration of erucic acid in fatty acid profile of meat was higher than concentration deemed safe for human consumption.