Oestrous Cycle | Menstrual Cycle |
Occurs in non-primates. | Occurs in primates only. |
There is estrus/heat production at the time of ovulation and copulation occurs only during that period. | There is no heat period and copulation occurs during any time of the cycle. |
The broken endometrium is reabsorbed. | The broken endometrium is passed out during menstruation. |
Examples- cow, sheep, rat, deer, dog, tiger, etc | Examples: monkeys, apes and human beings |