FORMALIN DENGAN BERBAGAI PELARUT TIDAK EFEKTIF UNTUK MENCEGAH PERKEMBANGAN TELUR ASCARIS LUMBRICOIDES

Abstract

Formalin is a preservative for faeces containing parasites. The formalin that frequently used
is formalin10% in distilled water, but it could also be dissolved in a 0.85% NaCl or sodium
phosphate buffer. The 0.85% NaCl serves to maintain the osmosic pressure of cell, while the
buffer solution serves to maintain the stability of pH of the solution. Purpose this research is
to determine whether there are differences in the ability of 10% formalin dissolved in
distilled water, 0.85% NaCl and sodium phosphate buffer in terms of maintaining the
morphology of cell and prevent the development of Ascaris lumbricoides eggs. This is an
experiment research using the randomized posttest control group design. This research using
three treatments, there are faeces added with formalin 10% in distilled water; 0.85% NaCl or
sodium phosphate buffer; and control without adding the formalin 10%. Each treatment
consists of 9 replication. Control and treatment groups are observed microscopically every
day. Based on the research. There is no difference in eggs cell morphology and development
of Ascaris lumbricoides eggs in all treatments. According to Kruskal Wallis and Mann
Withney test, P count > 0.05 which means there is no significant difference in time needed by
Ascaris lumbricoides eggs to become infective in every treatment. Formalin 10% in various
solvents is not effective as faeces preservatives, in particular to prevent the development of
Ascaris lumbricoides eggs due to they have already developed in average of 10 days.