男女 is used only for humans.

公母 is normally used on animals.

雄雌 is more academic.

公母 is usually used with terms closer to everyday life:

公鸡 / 母鸡 gōngjī / mǔjī for cock / hen

For biological terminology, usually 雄 / 雌 would be used:

雄蕊 / 雌蕊 xióngruǐ / cīruǐ for stamen / carpel

男女 is used only for humans.

公母 is normally used on animals.

雄雌 is more academic.

公母 is usually used with terms closer to everyday life:

公鸡 / 母鸡 gōngjī / mǔjī for cock / hen

For biological terminology, usually 雄 / 雌 would be used:

雄蕊 / 雌蕊 xióngruǐ / cīruǐ for stamen / carpel

Here are more characters for "male" or "female":

郎猫＝公猫

米猫＝母猫

儿马＝公马

骒马＝母马

草驴＝母驴

叫驴＝公驴

牡＝公的

牝＝母的

男女 is used only for human being. 公母 is normally used on animals. 雄雌 is more academical.

公母 is usually used with terms closer to everyday life: 公鸡/母鸡 cock/hen

In biological terminologies, usually 雄雌 would be used: 雄蕊/雌蕊 stamen/carpel

男女 is used only for humans. 

公母 is normally used on animals. 

雄雌 is more academic.

公母 is usually used with terms closer to everyday life:

公鸡 / 母鸡 gōngjī / mǔjī for cock / hen

For biological terminology, usually 雄 / 雌 would be used:

雄蕊 / 雌蕊 xióngruǐ / cīruǐ for stamen / carpel