Research shows red junglefowl improve the genetic quality of their offspring using sperm selection and by being promiscuous.
New research from the University of East Anglia (UEA) has shown female red junglefowl maximise the genetic quality of their offspring by being promiscuous.
Researchers studied the wild ancestor of the domestic chicken in a collaborative project with the University of Oxford, Stockholm University and Linköping University.
Findings published today (September 4, 2013) in the journal Proceedings of the Royal Society B, reveal mating with different males helps females produce offspring more resistant to diseases.
This is down to “cryptic female choice” – where an internal mechanism in their reproductive tract favours the sperm from males most genetically different to them.
The genes in question (Major Histocompatibility Complex; MHC) play a key role in detecting and fighting infections. By biasing fertilisation in favour of MHC-dissimilar males, females
increase the diversity of MHC within their offspring, providing better disease resistance.
Findings will be important for animal breeders as well as conservation projects because they show allowing multiple matings will produce the most disease resistant and genetically healthy offspring.
David Richardson, from UEA’s school of biological sciences, said: “Our research has shown the females don’t need to choose between males to produce the most healthy offspring.
“Rather, by mating with multiple males, they allow their internal choice mechanism to favour the most genetically different sperm.
“This could be the case in other animals – including humans, however the practicality of testing this in mammals would be very difficult, and obviously impossible in humans for ethical reasons.”
The research investigated both experimentally controlled natural matings and artificial inseminations and found the effect observed in natural matings was lost during artificial insemination.
“To optimise the quality of offspring produced in breeding programmes, we may need to make sure females mate with multiple males and that they avoid artificial insemination, which could lead to the genetic health of bred stocks being weaker,” added Prof Richardson.