Effects of a glyphosate-based herbicide on the oestrous cycle of rats

Abstract

Objective: To determine the effects of a glyphosate-based herbicide on the oestrous cycle of rats.

Methods: Fifteen adult Wistar rats were randomly divided into three groups. Group A served as the control group, while groups B and C received 250 and 500 mg/kg of glyphosate-based herbicide orally for five oestrous cycles, respectively. Stages of oestrous cycle, oestrous cycle index, length of cycle, oestrous cycle ratio, serum estradiol and progesterone levels were determined.

Results: The proestrus and oestrus stages of the glyphosate-based herbicide groups increased significantly (P<0.05), although proestrus in group C was not significantly different from the control group. There was a significant decrease in the metestrus and diestrus of the glyphosate-based herbicide groups (P<0.05). The oestrous cycle index of the glyphosate-based herbicide treated groups was altered; this was characterized by an increase in the oestrous index and a decrease in the metestrus and diestrus indexes. The proestrus index of group B increased, while that of group C decreased. The length of the cycle of the glyphosate-based herbicide groups significantly decreased from the 1st and 3rd week till the end of the study in groups B and C, respectively (P<0.05). There was a significant increase in the oestrous cycle ratio of the glyphosate-based herbicide groups compared to the control group (P<0.05). Though the estradiol and progesterone levels of the glyphosate-based herbicide groups increased and decreased, respectively, they were not significantly different from the control group.

Conclusions: Glyphosate-based herbicide at the doses of 250 and 500 mg/kg can alter the pattern of the oestrous cycle in rats.

Keywords

Estrogen / Glyphosate-based herbicide / Oestrous cycle / Oestrus / Progesterone

Conflict of interest statement

The authors declare that they have no conflict of interest.

Funding

The study received no extramural funding.

Authors’ contributions

Hafsat Yazeed Idris and Adewale Ayodeji Adeyeye conceived and designed the study. Hafsat Yazeed Idris, Adewale Ayodeji Adeyeye and Emmanuel Busayo Ibitoye participated in the data processing. Hafsat Yazeed Idris wrote the initial draft, while Adewale Ayodeji Adeyeye, Emmanuel Busayo Ibitoye and Millicent Ladi Umaru critically reviewed and edited the final draft.

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