The results from the present trial indicate that the inclusion of raw Ulva meal at levels of
up to 10 % in practical diets did not cause adverse effects on the growth performance,
nutrient utilization, digestibility and muscle fatty acid composition of rainbow trout.
Similarly, Valente et al. (2006) observed that 10 % dietary raw Ulva meal had no significant
effect on growth performance of European sea bass and Gu¨roy et al. (2007)
reported that dietary Ulva rigida meal inclusion at 10 % had no negative effects on the
growth of tilapia. Other studies have shown that a 5 % inclusion of dietary Ulva can have a
positive influence on the growth performance of black sea bream Acanthopagrus schlegeli
(Nakagawa et al. 1993) and snakehead Channa striatus (Hassan and Hashim 1995). In the
present study, the inclusion of autoclaved Ulva meal, at both inclusion levels, led to
significant reductions in body protein levels. This was not the case when using raw Ulva
meal. No other body composition parameters (i.e., moisture, ash and lipid) were affected
by the dietary treatments.