The purpose of this investigation was to determine the interrelationships of the various sexual and aggressive behaviors exhibited by Hereford bulls in sexual performance (serving capacity) tests and to determine the extent to which these interrelationships change with age (maturity). Correlation matrices were constructed for the frequencies of sexual and aggressive behaviors exhibited by two g...

BACKGROUND Antisocial personality and psychopathic traits have constantly been found to accompany criminal and aggressive behaviors, but little attention has been given to aspects of character maturity and its relation to such behaviors. The present study investigated (1) whether level of character maturity (low, medium, and high) is associated with amount of aggressive antisocial behaviors (AA...

age and growth of mesopotamian barb, capoeta damascina, were studied in the zayandehrud river, in central iran, from march 2007 to april 2008. among the 689 specimens studied, age groups in males ranged from 1+ to 9+ and that in females ranged from 1+ to 10+. the sex ratio (1m:1.6f) was not significantly different from 1:1 ratio. maximum fork length and weight was 39 cm and 1,115 g for males an...

TO THE EDITOR: Recently, Massaro and Massaro (4) demonstrated a sexual dimorphism of alveolar size in male and female adult rats and mice and that estrogen receptor (ER)and ERare required for this sexual dimorphism. Our group recently showed that a similar phenomenon of sexual dimorphism presents in airway responsiveness to sex hormones in rabbits. We studied the direct effect of sex hormones (...

Olfaction is an important sensory modality for mate recognition in many mammal species. Odorants provide information about the health status, genotype, dominance status and/or reproductive status. How and when odor profiles change during sexual maturation is, however often unclear, particularly in free-ranging mammals. Here, we investigated whether the wing sac odorant of male greater sac-winge...

Onset of sexual maturation is a trait of extreme importance both evolutionarily and economically. Unsurprisingly therefore, domestication has acted to reduce the time to sexual maturation in a variety of animals, including the chicken. In comparison with wild progenitor chickens [the Red Junglefowl (RJF)], domestic layer hens attain maturity approximately 20% earlier. In addition, domestic laye...

traditional poultry production has changed to a considerable industry after few decades. now, poultry industry is one of the main sectors to obtain the required protein for human consumption. prediction of the weight and number of eggs according to economic traits can improve the efficiency of production and the profit of producers. in present study, the weight and number of eggs in mazandaran ...

INTEREST in the genetic effects of irradiation on quantitative characters usually takes the form of two questions. Does irradiation effect a genetic change in the mean of quantitative characters such as human intelligence? Does irradiation induce genetic variance in quantitative characters that could be utilized by the plant or animal breeder for genetic improvement? Experimental data relevant ...

the data of this study were collected by indigenous chicken breeding centers in the west azerbaijan for 11 generations. the (co) variance components, heritability's, correlations between traits and breeding values were estimated by multi-trait animal model using wombat software. the genetic trends of traits over 11 generations of selection, using average function of breeding values per gen...

PURPOSE Sexual abstinence has become the primary response to adolescent pregnancy and sexually transmitted infection (STI) prevention. However, most abstinence programs are based on adult ideas of abstinence, and little is known about how adolescents themselves conceptualize sexual abstinence. METHODS In this qualitative study, we conducted semi-structured exploratory interviews with 42 adole...