The present study was conducted to evaluate the responses of Tamoxifen (TAM) administration on sexual maturity, productive and reproductive performance and blood parameters in two local juvenile female strains. Ninety females from each of Gimmizah and Bandarah strains at four weeks of age were divided into three equal groups involving 30 chicks per each and injected intramuscularly with TAM twi...

The Neurospora crassa Asm-1+ (ascospore maturation 1) gene encodes an abundant nucleus-localized protein required for formation of female structures and for ascospore maturation. Deletion mutants of Asm-1+ are "ascus-dominant," i.e., when crossed to wild type, neither Asm-1+ nor Asm-1 delta spores mature. To explain this behavior, we considered three models: an effect of reduced dosage of the g...

Analysis of sexual selection and sexual isolation in Drosophila mojavensis and its relatives has revealed a pervasive role of rearing substrates on adult courtship behavior when flies were reared on fermenting cactus in preadult stages. Here, we assessed expression of contact pheromones comprised of epicuticular hydrocarbons (CHCs) from eclosion to 28 days of age in adults from two populations ...

Wild and domesticated Atlantic salmon males display large variation for sea age at sexual maturation, which varies between 1-5 years. Previous studies have uncovered a genetic predisposition for variation of age at maturity with moderate heritability, thus suggesting a polygenic or complex nature of this trait. The aim of this study was to identify associated genetic loci, genes and ultimately ...

Airway smooth muscle (ASM) from infant guinea pigs has less spontaneous relaxation during stimulation than ASM from adults. Inhibition of cyclooxygenase (COX), which catalyzes the production of prostanoids, increases this relaxation in infant ASM and abolishes age differences, thus suggesting that prostanoids reduce relaxation in infant ASM. In this study, we investigated whether leukotrienes a...

The grey mullet fingerling were imported to Iran in 1997 from Hong Kong and in coastal fish pond of north part of Iran were successfully cultured in order to obtain broodstocks and induce artificial reproduction. Seasonal changes in serum concentrations of Testosterone, 17-β Estradiole (E2), 17-α Hydroxy Progesterone and also the level of calcium, Triglyceride and cholesterol in females grey mu...

The higher costs of sons compared with daughters extends to a negative effect of brothers on the lifetime reproductive success of their siblings in subsistence and preindustrial societies. In societies with fewer resource constraints, one might expect that these effects would be limited or non-existent. This study investigates the costs of brothers and sisters in a contemporary western society ...

OBJECTIVE To assess the growth and sexual maturity of non-handicapped children with birth weight less than 2000 g at 12 years. DESIGN Prospective cohort study. SETTING Infants discharged from a Neonatal Special Care Unit of a referral hospital with birth weight less than 2000 g between 1987-1989 and followed up till the age of 12 years. METHODS The height, weight and head circumference wa...

BACKGROUND Limiting allergen exposure in the sensitization phase has been proposed as a means of primary prevention of asthma, but its effectiveness is debated. HYPOTHESIS Primary prevention of asthma is more effective in limiting asthma symptoms in young guinea pigs compared with adults, whether males or females. METHODS The following experimental groups were used: young/young, sensitized ...