Sixteen mature
Bagrus bayad
of both sexes (8 males and 8 females) were used to evaluate a trial for spawning
induction using GnRHa combined with domperidone during spawning season. The experiment was carried out during
May 2014. Fish were divided into 4 groups. Group 1 was control males and females
Bagrus bayad
, group 2 was
females
Bagrus bayad
treated with dopamine antagonist (domperidone) alone, group 3 was females
Bagrus bayad
treated with domperidone and gonadotropin releasing hormone analogue (GnRHa), and group 4 was males
Bagrus
bayad
treated with GnRHa and domperidone. GnRHa was used in the present study by dose of 20 ug/kg and dose
of domperidone was 5 mg/kg. Results showed that no evidence for spawning induction. Histological examination
showed structural changes in ovary of group 2 and group 3 in comparison to control ovary but there was no obvious
change between structure of ovary of group 2 and group 3. In addition to, histological examination showed structural
changes in the testis of group 4 in comparison to control testis. In both sex, histological examination did not identify
any evidence of spawning. In conclusion, domperidone and/or GnRHa induced histological changes in the ovary and
testis of
Bagrus bayad
but did not induce spawning. Further studies are needed with higher doses of GnRHa and/or
carrying out the experiment during mid or late spawning season of
Bagrus bayad
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