The oestrous cycle in the Norwegian lemming Lemmus lemmus (L.)

Abstract

In vaginal smears of Norwegian lemmings swelling of leucocytes was prevented by quickly drying the effluent using a hairdryer. The mean length of the oestrous cycle in captive lemmings was 5.6 days. About half of the animals rarely cycled and some spent the 2 weeks test-period in constant oestrus or dioestrus. It is suggested that the Norwegian lemming, like many microtines, is an induced ovulator, but that the system is flexible and modulated by social and other external stimuli.

Keywords

• Mammalia
• Rodentia
• data collection
• ecology
• controlled condition