We analysed the environmental impact of different feeds
of known composition generically. That is, generic impacts
were calculated by using an average FCR and a typical feed
composition not specifically related to any of the farms
surveyed. Unfortunately, the data from our surveys did not
enable us to account for the different feed brands used by
individual farmers. When feed compositions and origin of
feed ingredients were compared, however, we found
different environmental impacts per ton striped catfish
(Table 6). The influence of specific data is unclear, but we
suspect it results in interesting differences (Pelletier et al.
2009), especially as the farm comparison in this study
identified FCR as the factor causing higher impacts on
seven of the 28 farms. We therefore advise carrying out an
LCA with at least three different feed-mills, each using
different feed ingredients and repeating surveys on farms
using this feed.