Monocrotophos Impairs the Fertility of Male Rats

Abstract

Monocrotophos, an organophosphorous pesticide which is used extensively in Sri Lanka, was investigated for its effects on male reproductive function, using , rats. lVlonocrotophos. was administered oratly (3.5 mg kg-' and 1.7-5 mg kg-'.1 for three alternative days and these rats were subjected t6 serial mating (approximately at weekly intervals) from day 3 following treatment. Monocrotophos inhibited fertilit\, (in terms of uterine implants and implantation index) frqin day 3 post-treatment and the fertility was restored by day 28 post-treatment. The antifertility effect was accompanied by reduced sperm content in the ejaculates (in terms cf vaginal sperm count index) and in the cauda epididymis, impairment of motility of cauda epididymal sperm and an elevation of pre-implantation loss. In contrast, monocrotophos had no significant effect on libido, quantal pregnancy, fertility index, food and water intake, body weight, selected haematological parameter (RBC, WBC, PCV and ESR), systolic blood pressure or heart rate. It is concluded that moiocrotophos is detrimental to male fertility. This effect stems mainl1'from oligozoospermia and increased pre-implantation losses.