Reproductive effort and survival in breeding females (n = 20).

Univariate Cox analyses: hazard ratio point estimates and 95% confidence intervals (CI) and p-values (2-tailed) from Wald tests are reported. Null hypothesis (no effect): hazard ratio = 1. Ratios 1 negative effects of a given parameter in units of the respective variable on survival. Except age at pairing, all parameters refer to a defined period of time (the first two years after delivery of the first litter) in order to standardize the data.alactation effort defined as: number of sucklings * their respective lifespan before weaning at approx. 90 days [10].#Note that the units of some variables differ between the descriptive (mean ± SD) and the inferential illustration in the cox model. This transformation was necessary to better display the hazard ration point estimates.