The effects of 1/1000 field recommended concentration of the organophosphorus
compounds; edifenphos and glyphosate on the immune response and protein contents
were investigated after different time intervals. The cell mediated immune
response assessed by proliferative response of splenocytes to mitogens;
phytohemagglutinin (PHA) and concanavalin A (Con A) for T cell and
lipopolysaccharide (LPS) for B cell decreased significantly in tems of the level
of stimulation index in the treated fish and reached maximal depression after 4
weeks. Humoral immunity assessed as splenic antibody plaque forming cells (PFC)
measured after 5 days in vitro immunization to sheep erythrocytes (SRBC's) were
suppressed in a concentration dependent pattern by the two compounds. The
estimated ED50 for the PFC/10(6) cells of edifenphos and glyphosate were 1.48 x
10(-2) uM and 1.65 x 10(-2) uM respectively. The data also showed that serum
antibody titres in the treated fish were decreased in a time dependent manner.
The total protein content of serum treated with the two pesticides was decreased
after different time periods compared with control. The blood serum of treated
and untreated Tilapia nilotica were analyzed electrophoretically for protein
components and the percentage of proteins in each fraction was determined.