activated protein
synthesis and significantly increased collagen content of
intramuscular connective tissue [30] and this indicated that both
Spirulina and Ropadiar diets improved the protein retention in
musculature. The serum antioxidant activities were enhanced
in Spirulina diets due to the presence of phycobiliproteins such
as C-phycocyanin (CP) and allophycocyanin [5] while in
Ropadiar diets due to both Carvacrol and thymol have
excellent antioxidant properties [31]. Both Spirulina and
Ropadiar diets reduced the mortality of experimentally
infected O. niloticus and these results may be attributed to the
inhibition of growth of different microorganisms by Carvacrol
and thymol [32] through disintegration of the membrane of the
bacteria, leading to the release of membrane-associated
material from the cells to the external medium. Moreover,
terpenoids and phenylpropanoids can penetrate the membrane
of the bacteria and reach the inner parts of the cell because of
their lipophilicity [33] and also their aromaticity [34] which is
responsible for their antibacterial activity. While the results of
Jade Spirulina® in immune enhancing properties may be due to
the fact that antibodies produced through the feeding [35].