Effects of Fenitrothion on Life History Parameters of the RotiferBrachionus calyciflorus

Abstract

The effects of fenitrothion on life history parameters, the production of resting eggs and hatching of resting eggs of the rotifer Brachionus calyciforus were studied on the individual and population level. Neonates (<4 h-old) were individually cultured in six concentrations (0

Assessing the impacts of dimethoate on rotifers′ reproduction through the pre-exposure history

“…This changing pattern displayed characteristics of hormesis, featured by conversion from low-dose stimulation to high-dose inhibition. A database of studies in which hormesis has been observed shows that egg and offspring reproduction for low-dose enhancement and that the responses are most often observed including fenitrothion (Lv et al, 2010), aldrin (Huang et al, 2007), chlordecone (Zha et al, 2007) on rotifer, lindane (Brown et al, 2003), naphthalene and 1.2-dimethylnaphthalene on copepod (Saiz et al, 2009), chlorpyrifos (Zalizniak and Nugegoda, 2006) and triazophos (Li and Tan, 2011) on daphnia. It implied that dimethoate enhanced the reproductive output of rotifers at low concentrations due to hormesis which possibly occurs when a species is under some moderately low stress.…”

Expression variations of two retinoid signaling pathway receptors in the rotifer Brachionus calyciflorus exposed to three endocrine disruptors

“…Among the compounds tested in this study, fenitrothion was the only one that did not induce significant change the relative mRNA levels of RXR and RAR. Ferrando et al (1996) and Lv et al (2010) highlighted fenitrothion effects on B. calyciflorus reproduction such as a decrease of the intrinsic rate of natural increase, the net reproductive rate, and the lifetime reproduction. These disturbances could be the consequence of indirect or direct effects of fenitrothion on the endocrine system of B. calyciflorus.…”

“…Our results showed no effect of fenitrothion on RXR and RAR mRNA levels suggesting that retinoid signaling pathways seem not involved in the EDC effects caused by fenitrothion. Several hypotheses could explain these results, starting with the fact that the effects of fenitrothion on B. calyciflorus reproduction observed in Ferrando et al (1996) and Lv et al (2010) were measured after several days of exposure, while our study focused on studying changes in the RXR and RAR mRNA levels, from the first 24 h of exposure. Consequently, we can assume that, if endocrine disruption effects of fenitrothion are directly mediated through retinoid pathways, they could occur after 24 h of exposure of B. calyciflorus.…”

“…In fact, Preston et al (2000) demonstrated that exposures to flutamide (non-steroidal anti-androgen) at 1 and 10 μg L −1 decreased the fertilization rate and the resting egg production of Brachionus calyciflorus females. In the same way, Ferrando et al (1996) highlighted that the organophosphorus pesticide fenitrothion decreased the intrinsic rate of natural increase, generation time, net reproductive rate, and life expectancy of B. calyciflorus; while Lv et al (2010) observed that fenitrothion caused an increase in the duration of the juvenile period, reproductive period, and lifetime reproduction in the same organism. Recently, Gismondi et al (2019) underlined an increase of the number of oocytes in B. calyciflorus neonate females which mothers has been exposed to the cyproterone acetate, an anti-androgen and progestogen synthetic steroid.…”

Sumithion usage in aquaculture: benefit or forfeit?

“…3). Lv et al (2010) reported a significant reduction in the number of resting eggs in rotifer, Brachionus calyciflorus following exposure to sumithion. In a study, Leboulanger et al (2011a) found that sumithion adversely affects the young stages of Thermocyclops decipiens and Diaphanosoma excisum.…”