Uterine priming and pig fertility

This pig fertility project will explore the influence of pre-breeding seminal components on gilt fertility.

If a female pig gets a sterile breeding at her first oestrus, it increases her fertility when bred with fertile semen 21 days later at her second oestrus. This is because semen changes her uterine immune response from one where a foreign object (e.g. embryo) is rejected to one where it is tolerated.

We want to explore whether both inseminations can occur during a single oestrus, i.e.. whether a sterile breeding at onset of second oestrus will affect fertility to a fertile insemination 24 hours later.