Scientists have determined a way to genetically control the populations of livestock pests, limiting their ability to reproduce and cause trouble for farmers.

The Australian sheep blowfly (Lucilia cuprina) is a deadly pest that continues to ravage livestock throughout Australia and New Zealand with its parasitic and flesh-eating larvae. A similar insect, the New World screwworm, affected livestock in North and Central America in a similar fashion, but were eradicated from these areas using an extremely costly sterilization plan.

Now, researchers from North Carolina State University have determined how to cull sheep blowfly and New World screwworm populations in a less expensive and environmentally impactful manner.

According to a study published in the journal Insect Biochemistry and Molecular Biology, scientists have genetically modified strains of female blowflies so that they are dependent on a common and inexpensive antibiotic for survival. If not presented with this antibiotic within the final stages of larval development, female offspring will die, leaving that generation of blowfly without a means of reproducing.

The researchers argue that by specifically targeting females, and by modifying the flies so that there is an inexpensive remedy to save females if they so choose to, they can control the pest population numbers - avoiding the potential environmental consequences of full eradication.

Interestingly, this genetic modification had an unforeseen effect. Female blowflies affected with the lethal mutations wound up turning a deep crimson red - an obvious marker for their inevitable death.

The authors of the study say that this was a harmless change that occurred after a fluorescent "marker protein" was over-expressed. Now, it could help farmers and scientists identify affected female populations more easily.

Nature World News previously reported how genetic modification could eradicate mosquito populations in a similar manner. However, critics argue that there are bound to be ecological consequences for such actions.