introduction: sexual dimorphisms in biological structures such as brain and behaviour have been widely recognized in animals and humans. the purpose of this study was to examine whether there are sex differences in the size of the cerebellum with other body traits, such as the head, tail and brain. methods: twelve grasscutters comprising of 6 males and 6 females were used in this study. each br...

Little is known about the importance of trade-offs between ageing and other life history traits, or the effects of ageing on sexual selection, particularly in wild populations suffering high extrinsic mortality rates. Life history theory suggests that trade-offs between reproduction and somatic maintenance may constrain individuals with higher initial reproductive rates to deteriorate more rapi...

the present investigation aimed to conduct a genetic study of dairy cattle and buffalo bulls based on economic traits and their phenotypic correlation. the means of various economic traits in both the species are presented. cattle bulls reported a better libido score, flehmen response, requirement of mounting stimulus and semen volume, conception rate and expected predicted difference for milk ...

Women's preferences for men's masculinized faces and voices were assessed after women (n = 331) were primed with images of male-on-male aggression, male-on-female aggression, pathogens, and neutral scenes. Male-on-male aggression and pathogen primes were associated with increased preference for masculine traits, but the same effect emerged in the neutral condition. We show the increased prefere...

The present study aimed to estimate heritability, genetic and phenotypic correlations between body weight and body measurement traits in Iranian Makuei sheep. The used data were collected from 1989 to 2012 at Makuei Sheep Breeding Station in Maku (West Azarbayjan province). The data included body weight and five body measurement traits (body length (BL), heart girth (HG), withers height (WH), r...

The present investigation aimed to conduct a genetic study of dairy cattle and buffalo bulls based on economic traits and their phenotypic correlation. The means of various economic traits in both the species are presented. Cattle bulls reported a better libido score, Flehmen response, requirement of mounting stimulus and semen volume, conception rate and expected predicted difference for milk ...

a total of 2000 records of egg quality of 746 birds and body weight data from 17th generation of fars native fowl breeding station were used to estimate the genetic parameters of egg quality and body weight traits. six univariate animal models with different random effects were fitted for each trait. a model with direct additive genetic and maternal permanent environmental effects was the most ...

the main aim of this research was to estimate the genetic and phenotypic parameters for productive and reproductive traits of esfahan native chickens. traits included body weights at hatch (bw1), 8 weeks of age (bw8), 12 weeks of age (bw12), and at sexual maturity (wsm)], age at sex maturity (asm), egg number (en), average egg weight (aew) in the first 12 weeks of production, and egg production...