2014 Volume 30 Issue 4 Pages 119-129
The objectives of this study were to evaluate and compare the environmental impacts and feed costs of two beef-fattening experiments using linseed oil soap fatty acids (LS) by the life cycle assessment (LCA) method. Crossbred heifers between Japanese Black sires and Holstein dams were used for two fattening experiments. In the first experiment, three treatments were compared; total mixed rations (TMR) were supplied from 19 to 27 months of age (Control; C1 group), 2.9% LS on TMR from 19 to 27 months of age (L1 group), and 2.9% LS on TMR from 18 to 27 months of age (L1e group). In the second experiment, all heifers were fed from 19 to 27 months of age and the three treatments were designed; Conventional TMR (C2 group), 2.7% LS on TMR (L2 group), and 2.7% linseed and rape seed oil soap (LRS) on TMR (LR2 group). The amounts of emitted pollutants and energy consumption from fossil fuel combustion and volatilization inside the system boundary (including feed preparation, feed transportation, barn, animal, and composting) were calculated based on data from each group. Environmental impacts of global warming, acidification, eutrophication, and energy consumption were estimated. The functional unit was 1.0 kg of average daily gain. The results showed that contributions to environmental impacts of global warming, acidification, and eutrophication in LS or LRS groups were smaller than non-supplemented groups (Control). This was due to the effects of methane mitigation and reduction of amounts of feed consumption caused by LS or LRS supplementation. Environmental impacts of the L1e group were smaller than the L1 group in all impact categories. In general, there was the trade-off between feed costs and mitigation effects of environmental impacts, and the LR2 group showed the lowest increase in feed costs and the highest reduction of environmental impacts in this study.
