Zearalenone toxicosis on reproduction as estrogen receptor selective modulator and alleviation of zearalenone biodegradative agent in pregnant sows

Background Zearalenone (ZEA) is a resorcylic acid lactone derivative derived from various Fusarium species that are widely found in food and feeds. The molecular structure of ZEA resembles that of the mammalian hormone 17 beta-oestradiol, thus zearalenone and its metabolites are known to compete with endogenous hormones for estrogen receptors binding sites and to activate transcription of oestrogen-responsive genes. However, the effect of long-term low-dose ZEA exposure on the reproductive response to Bacillus subtilis ANSB01G culture for first-parity gilts has not yet been investigated. This study was conducted to investigate the toxic effects of ZEA as an estrogen receptor selective modulator and the alleviating effects of Bacillus subtilis ANSB01G cultures as ZEA biodegraders in pregnant sows during their first parity. Results A total of 80 first-parity gilts (Yorkshire x Landrace) were randomly assigned to four dietary treatments during gestation: CO (positive control); MO (negative control, 246 mu g ZEA/kg diet); COA (CO + B. subtilis ANSB01G culture with 2 x 10(9) CFU/kg diet); MOA (MO + B. subtilis ANSB01G culture with 2 x 10(9) CFU/kg diet). There were 20 replications per treatment with one gilt per replicate. Feeding low-dose ZEA naturally contaminated diets disordered most of reproductive hormones secretion and affected estrogen receptor-alpha and estrogen receptor-beta concentrations in serum and specific organs and led to moderate histopathological changes of gilts, but did not cause significant detrimental effects on reproductive performance. The addition of Bacillus subtilis ANSB01G culture to the diet can effectively relieve the competence of ZEA to estrogen receptor and the disturbance of reproductive hormones secretion, and then ameliorate toxicosis of ZEA in gilts. Conclusions Collectively, our study investigated the effects of feeding low-dose ZEA on reproduction in pregnant sows during their first parity. Feeding low-dose ZEA could modulate estrogen receptor-alpha and -beta concentrations in specific organs, cause disturbance of reproductive hormones and vulva swelling, and damage organ histopathology and up-regulate apoptosis in sow models. Diet with Bacillus subtilis ANSB01G alleviated negative effects of the ZEA on gilts to some extent.

Automated summary

In this study, the effects of low-dose ZEA feeding on reproduction in pregnant sows during their first parity were investigated. Feeding low-dose ZEA alters the concentrations of estrogen receptor-alpha and -beta in specific organs, disrupts reproductive hormones secretion and vulva swelling, and causes mild organ histopathological damage and increased apoptosis in sow models. The addition of Bacillus subtilis ANSB01G culture to the diet can alleviate the negative effects of ZEA on gilts to some extent.