Artificial insemination in cattle with DNA‐treated sperm

Abstract

We have investigated the use of sperm cells as vectors for transferring exogenous DNA into the genome of cattle by artificial insemination with DNA‐treated sperm. First we demonstrated the DNA‐binding ability of cattle sperm with radioactively labeled DNA. For artificial insemination ejaculated semen was washed and incubated with 1 μg DNA/10⁶ sperm for one hour at 37°C. Three hundred synchronized heifers were inseminated once with a dose of 40×10⁶ sperm. Forty‐five calves and 41 fetuses were obtained. Southern analysis revealed in one calf a signal after probing with the 1 kb Pst I fragment of pSV2‐cat.