% pubman genre = article
@article{item_3479332,
title = {{Bonobo mothers have elevated urinary cortisol levels during early but not mid or late lactation}},
author = {Nurmi, Niina and Sonnweber, R and Sch{\"u}lke,, O and Moscovice, Liza R. and Deschner, Tobias and Hohmann, Gottfried},
language = {eng},
issn = {0032-8332},
doi = {10.1007/s10329-022-01044-7},
publisher = {Japan Monkey Centre},
address = {Inuyama, Aichi, Japan},
year = {2023},
date = {2023},
abstract = {{In mammals, the costs of reproduction are biased towards females. Lactation is particularly energetically expensive, and{\textless}br{\textgreater}behavioral and physiological data indicate that maternal effort during lactation induces energetic stress. Another source of{\textless}br{\textgreater}stress in females is male aggression directed towards them when they are cycling. Evaluating the costs of reproduction in{\textless}br{\textgreater}wild and mobile animals can be a challenging task, and requires detailed information on state-dependent parameters such as{\textless}br{\textgreater}hormone levels. Glucocorticoid (GC) levels are indicative of nutritional and social stress, and are widely used to assess the{\textless}br{\textgreater}costs of reproduction. We investigated variation in urinary levels of cortisol, the main GC in female bonobos (Pan paniscus),{\textless}br{\textgreater}between and within reproductive stages. Female chimpanzees (Pan troglodytes), the closest living relative of the bonobos,{\textless}br{\textgreater}are often exposed to intense aggression from males, which causes a significant rise in their cortisol levels during the phase{\textless}br{\textgreater}of their maximum fecundity. In bonobos, males compete for access to fertile females, but aggressive male mating strategies{\textless}br{\textgreater}are absent in this species. Therefore, we expected that GC levels of cycling female bonobos would be lower than those of{\textless}br{\textgreater}lactating females. Due to the long period of offspring care in bonobos, we expected that GC levels would remain elevated{\textless}br{\textgreater}into the late stage of lactation, when immatures gain body weight but may still be nursed and carried by their mothers. We{\textless}br{\textgreater}found elevated urinary GC levels only during the early stage of lactation. The GC levels of cycling females did not differ{\textless}br{\textgreater}from those in the mid or late lactation stage. Behavioral strategies of female bonobos may allow them to compensate for the{\textless}br{\textgreater}elevated energetic demands of lactation and prolonged maternal care.}},
journal = {{Primates}},
volume = {64},
pages = {215--225},
}