Reproduction of Pseudomys novaehollandiae (Muridae) in the laboratory

Abstract

Oestrous cycle, gestation, parturition, litter size, lactation and sexual maturity were studied in a captive colony of the Australian murid P. novaehollandiae. The pattern of reproduction is similar to that of other murids, although oestrous cycle (6.0 ± 1.26 days) and gestation period (31.5 ± 0.96 days) are longer than those in the laboratory rat and mouse. Changes in the external appearance of the vagina were too inconsistent to identify stages of the oestrous cycle, but were of use in determining the stage of pregnancy or lactation. Parturition took place during the light phase of the day-length regime, with post-partum oestrus during the following dark phase. Weight changes in pregnant and lactating females were considered. The average litter size was 4.0 ± 1.03 with a range of one to six. Oestrus was inhibited during lactation and recurred about 24 days after parturition. Sexual maturity was earlier in females (13 weeks) than in males (20 weeks).