due to the importance of adult artemia in aquaculture, information regarding the digestive enzyme activities variation with inexpensive diets has great importance in artemia at different life stages. in this study, the effect of different inexpensive diets on digestive enzyme activities, including trypsin, amylse and lipase of artemia urmiana was investigated in different life stages. the exper...

Of 40 Drosophila species screened to date, a majority have shown some ability to at least initiate parthenogenetic development. In one case, Drosophila mangebeirai, natural populations are entirely female, making it the only obligate parthenogenetic species of Drosophila Only a few of the species that exhibit the ability to undergo early embryonic development of unfertilized eggs successfully r...

Genetic and sexual systems can be evolutionarily dynamic within and among clades. However, identifying the processes responsible for switches between, for instance, sexual and asexual reproduction, or cyclic and non-cyclic life histories remains challenging. When animals evolve parthenogenetic reproduction, information about the sexual mating system becomes lost. Here we report an extraordinary...

Parthenogenesis is a relatively rare reproductive mode in nature compared to sex. In social insects, the evolution of parthenogenesis has a notable impact on their life histories. Some termites with parthenogenetic ability produce numerous non-dispersing supplementary queens asexually, whereas other castes are produced via sexual reproduction. This asexual queen succession (AQS) system is adapt...

Mammalian parthenogenesis could not survive but aborted during mid-gestation, presumably because of lack of paternal gene expression. To understand the molecular mechanisms underlying the failure of parthenogenesis at early stages of development, we performed global gene expression profiling and functional analysis of parthenogenetic blastocysts in comparison with those of blastocysts from norm...

Mature bovine oocytes were activated with 7% ethanol followed by cytochalasin B or D treatment. Most oocytes extruded a second polar body and formed one pronucleus when treated with 7% ethanol alone [35/43 (81%)]. With ethanol followed by cytochalasin B or D, overall activation frequency was 70% (309/441), with activated oocytes containing two pronuclei. The cleavage rate was not significantly ...

Both a maternal and a paternal genomic contribution are necessary for completion of embryonic development in the mouse. Parthenogenetic embryos, with only a maternally inherited genome, and androgenetic embryos, with only a paternally inherited genome, fail to develop to term, and these two types of isoparental embryos fail in development in characteristic ways. In this paper we describe the co...

Androgenesis is the production of an offspring containing exclusively the nuclear genome of the fathering male via the maternal eggs. This unusual mating system is generally considered a male trait, giving to androgenetic males a substantial fitness advantage over their sexually reproducing relatives. We here provide the first empirical study of the evolutionary outcomes of androgenesis in a ha...

Oak gallwasps are cyclically parthenogenetic insects that induce a wide diversity of highly complex species- and generation-specific galls on oaks and other Fagaceae. Phylogenetic relationships within oak gallwasps remain to be established, while sexual and parthenogenetic generations of many species remain unpaired. Previous work on oak gallwasps has revealed substantial intra-specific variati...

Facultative reproductive strategies that incorporate both sexual and parthenogenetic reproduction should be optimal, yet are rarely observed in animals. Resolving this paradox requires an understanding of the economics of facultative asexuality. Recent work suggests that switching from parthenogenesis to sex can be costly and that females can resist mating to avoid switching. However, it remain...