Table 1.

Criteria for classification of gonadal phases

Gonad	Phase	The most represented germ cells observed in the gonads	Approximate timings of collection in 2016 to 2017
Ovary	Early	Oocytes with cytoplasmic polarization (<125 μm in diameter)	October, 2016
	Middle	Oocytes with accumulation of yolk and other components (126-200 μm in diameter)	December, 2016
	Late	Oocytes with accumulation of yolk and other components (201-275 μm in diameter)	February, 2017
	Premature/ mature	Oocytes with ‘U’-like germinal vesicles and GVBD (>276 μm in diameter)	April, 2017
Testis	Early	Spermatogonia	February, 2017
	Middle	Spermatogonia and primary spermatocytes	March, 2017
	Late	Secondary spermatocytes and spermatids	April, 2017
	Mature	Sperm	June, 2017