Female aspic vipers (Vipera aspis) are ‘‘capital breeders,’’ and delay reproduction until they have amassed large energy reserves. Data from an eight-year mark– recapture study on free-ranging vipers suggest that potential costs of reproduction were high for these animals, in terms of survival as well as growth and energy storage. Females that reproduced experienced higher mortality rates than ...

The purpose of this study was to analyze the reproductive cycle of the oyster Crassostrea gasar (= C. brasiliana) in the field and the laboratory. The reproductive cycle of the animals was evaluated in the field at Sambaqui Beach, Florianópolis, SC (27° 29'18″ S and 48° 32'12″ W) from May 2008 through November 2009. In July, the animals were in the resting stage. The early growth stage began in...

The organs of the adult reproductive system can undergo extensive remodelling, experiencing rapid changes in tissue mass and function. Much of this matrix remodelling is attributed to the action of matrix metalloproteinases. Matrix metalloproteinase family members are expressed in a highly-regulated manner in many reproductive processes, including menstruation, ovulation, implantation, and uter...

Predator–prey interactions play major and direct roles in the structuring of zooplankton communities. Asplanchna usually predates ciliates, rotifers, cladocerans and sometimes even copepods, its predation may drive not only the ecological, but also the evolutionary dynamics of prey populations. In the present study, the life-table demography and the population growth of Asplanchna brightwelli w...

Disposition has been shown to significantly affect feed intake and growth rates of beef cattle. However, little research has evaluated the effects of poor disposition, and methods to improve this trait, on reproductive function of beef females. Thus, two experiments were conducted to determine the effects of disposition and acclimation to human handling on reproductive function of mature cows a...

Estrogen receptors* ERα/NR3A1; ERβ/NR3A2 Endogenous: 17β-estradiol Regulation of cell growth and proliferation in multiple tissues (e.g., female reproductive tissues, bone, and CNS) Cancer, cardiovascular, immune and inflammatory, metabolic, neurological, reproductive ↑ MYC, NGF, BCL2, CXCL2, IGF1, TYMS; ↓ CD36, NDRG1, NCOR1, NCOA3 Clinical: Mixed agonists (e.g. tamoxifen, raloxifene, and torem...

Growth from conception to reproductive onset in African elephants (Loxodonta africana) provides insights into phenotypic plasticity, individual adaptive plastic responses and facultative maternal investment. Using growth for 867 and life histories for 2652 elephants over 40 years, we demonstrate that maternal inexperience plus drought in early life result in reduced growth rates for sons and hi...