Meet Cosmo the Frankenbull: Scientists genetically engineer a bull calf so that 75 per cent of its offspring will be male

*Cosmo has been modified using CRISPR to have an additional gene called SRY
*It was inserted into chromosome 17 and is known to initiate male development
*Around half of his female offspring with XX chromosomes will also inherit SRY
*It is believed this will make these genetic females develop into males
*This would result in 50% normal males, 25% XX females with SRY that develop as males and 25% normal females