Species richness is distributed unevenly across the tree of life and this may be influenced by the evolution of novel phenotypes that promote diversification. Viviparity has originated ∼150 times in vertebrates and is considered to be an adaptation to highly variable environments. Likewise, possessing an annual life cycle is common in plants and insects, where it enables the colonization of sea...

Unlike most domestic livestock species, sheep are widely known as an animal with marked seasonality of breeding activity. The annual cycle of daily photoperiod has been identified as the determinant factor of this phenomenon, while environmental temperature, nutritional status, social interactions, lambing date and lactation period are considered to modulate it. The aim of this paper is to revi...

1. Effects of endosulfan, malathion and carbaryl on circulating T4, T3 and T3/T4 ratio in the freshwater catfish, C. batrachus have been studied during reproductively active phases, i.e. vitellogenic and post-vitellogenic phases of its annual reproductive cycle. 2. Endosulfan provoked a significant increase in T4 and a decrease in T3 as well as the T3/T4 ratio. 3. Malathion decreased T3 and T3/...

This survey was aimed at detecting histological and histometrical changes of Common Carp ovaries in Khouzestan Province climate conditions. The goal was to determine the ovarian status in the breeding period of the reproductive cycle. Ovaries of 49 Common Carp brooders were collected from April to October, 2010. The samples were taken from the anterior, median and posterior portions. 5-6µ secti...

Using 15 years of data from a stable population of wild Eurasian beavers (Castor fiber), we examine how annual and lifetime access to food resources affect individual age-related changes in reproduction and somatic condition. We found an age-related decline in annual maternal reproductive output, after a peak at age 5-6. Rainfall, an established negative proxy of annual resource availability fo...

To assess the role of the pineal gland in the regulation of ovarian activity, female catfish were exposed to various combinations of photoperiods during the postspawning period of the annual reproductive cycle. Ovarian recrudescence and vitellogenin synthesis were accelerated after pinealectomy in catfish maintained under short photoperiod (9L : 15D) at 25 °C. However, at 25 °C, under long (14L...

A cold room assisted vapor-compression refrigeration cycle is dynamically modeled in a year and optimized. Total annual cost (TACO) and coefficient of performance (COP) are selected as two objective functions. Both cold room and refrigeration cycle parameters are considered as design variables. Moreover, three working fluids included R22, R134a and R407c are examined. The optimum Pareto front r...