Research Article: Study on histophysiological effects of dietary soy extract on gonads in Yellowfin Seabream, Acanthopargus latus

The present study has performed to investigate the effects of different levels of soy phytoestrogens on gonad histological structure and E۲ and P۴ sex hormone levels in Yellowfin Seabream (Acanthopagrus Latus).  A total of ۶۰ Yellowfin Seabream with an average weight of ۷۳.۷۰ ± ۹.۵۳ kg were divided into four groups: one control group that were feeding with standard diet without any extract and three treatment groups that received different doses of diet containing soy extract (۲.۵, ۵ and ۷.۵ percent) in three replicates. Fish were fed at the rate of ۳% of body weight twice a day for ۱۴ days. Samples were taken in days of ۰, ۷, ۱۰ and ۱۴. Gonad sampling was done for histological studies and for evaluation of E۲ and P۴ levels, blood samples were collected from tail vein. The results showed that different doses of soy extract have various effects on gonads and in total, considering that A. latus is a protandrous hermaphroditic fish, by increasing the dose and days of exposure to soybean extract, the ovary returned to the previtellogenic state and also the appearance of testicular tissue in gonad was observed. Also, the measurement of E۲ and P۴ hormone levels showed that generally, decrease in  plasma E۲  levels  and increase  in  plasma P۴  levels was  seen  after feeding meal diets containing ۲.۵%, ۵% and  ۷.۵%  soy extract  in yellowfin seabream (P>۰.۰۵), which supported the findings that soybean phytoestrogens lead to endocrine disruption by different mechanisms, as shown in previous studies.

کلیدواژه ها:

Phytoestrogen ، Soy ، gonad ، Yellowfin Seabream