The amino acid spectrum was studied in two Cuban fish species - Gambus
ia puncticulata and G. bucheri from Cuba. Of nine essential amino acid
s (EAA) identified in total, statistically significant differences bet
ween the species were found only in the quantitative value of methioni
ne, but nearly significant differences were observed in arginine and i
soleucine. Between eight nonessential amino acids (NEAA), very signifi
cant differences were found only in alanine. The hierarchy subsequence
of the quantitative values of amino acid apectrum is, of course, coin
cident in both species. In wild populations of G. puncticulata from va
rious types of aquatic ecosystems, coincident values of leucine, lysin
e, valine, phenile, tyrosine and histidine were found. As to the local
ities, statistically significant differences were found in isoleucine,
arginine, threonine and methionine. In the other AA registered in bot
h fish species, significant differences also occurred. Significant dif
ferences in the quantitative values of AA between G. puncticulata wild
populations with natural food available and those in G. puncticulata
captive population reared for a long time under experimental condition
s (and fed on artificial synthetized food) were found in threonine and
serine only.