Abstract Learning ability, which allows individuals to adjust their behaviour changing environmental conditions, has a considerable positive impact on individual fitness. However, in addition benefits, learning also incurs cost, means that investment and maintaining learned skills can lead trade-offs impacting other biological functions. Here, we tested whether trade-off exists between reproduc...

Mycotoxin zearalenone is a phytoestrogenic substance that can disrupt the functioning of organs reproductive system cows. At same time, hyperestrogenic state occurs, which
 leads to overeating, multiple unsuccessful inseminations and infertility cows.
 The purpose research investigate effect single application drugs based on aromatase inhibitors main biochemical hormonal parameters bl...

During adaptation to different habitat types, both morphological and behavioral traits can undergo divergent selection. Males often fight for status in dominance hierarchies and rank positions predict reproductive success. Ecotypes with reduced fighting abilities should have low reproductive success when migrating into habitats that harbor ecotypes with superior fighting abilities. Livebearing ...