The first trial in 1994–1995 had duration of 85 days, while the duration for the second
trial of 1995–1996 was 83 days. The GIFT and Egypt 88 strains began to die at 11 jC, and
the Sudan 78 strain at 9.8 jC. GIFT strain experienced total mortality at 8.4 jC, and this
parameter was 7.4 jC for Egypt 88 and Sudan 78 strains (Tables 1 and 2; Figs. 1 and 2).
These data indicate that lower lethal temperature of GIFT strain was higher (P < 0.05) than
the other two strains. The results for cold tolerance for the 2 years were virtually identical
even though the rankings of the sizes of the fish for the 2 years were different.