author(s)
R Hamsavalli, Dr. J Jaculine Pereira, Dr. K Karal Marx and Dr. R Jeya Shakila

abstract
In Lepidocephalichthys thermalis the cDNA was synthesized from the ovary tissues and polymerase chain reaction were carried out for gonadotropin releasing hormone II, gonadotropin releasing hormone III, luteinizing hormone and follicle stimulating hormone genes; the PCR products sizes of the four genes were 270-bp, 250-bp, 290-bp and 260-bp respectively. The expressions of the four genes were compared at different stages of oogenesis and in the initial phase perinucleolus stage follicle, only gonadotropin releasing hormone II & III genes were expressed. In cortical alveolus stage, lipid droplet stage and mid vitellogenic stage except luteinizing hormone gene all other genes were expressed. In post vitellogenic stage follicle except follicle stimulating hormone genes all other genes were present. When the expressions of the four genes were compared at different photoperiods, it showed that the expression of genes were very less during 9:00 AM, moderate during 10:00 AM and was high during 12:00 noon.