Last week’s National Institute for Animal Agriculture (NIAA) annual conference in Omaha focused on the “Precautionary Principle,” examining how a bias toward extreme caution can hamper development of tools to improve agriculture and food production.
Mark Allen, PhD, director of marketing and genomics with TransOva Genetics described how assisted reproduction tools (ARTs), coupled with genomics, can accelerate the rate of genetic progress by two to eight times. Several of these tools already have contributed dramatically to genetic progress – artificial insemination (AI) since the 1950s, embryo transfer since the 1970s, in-vitro fertilization and cloning since the 1990s and sex-sorted semen since the early 2000s. Activists have resisted the implementation of ARTs, and that resistance has increased as new tools such as genetic engineering and gene editing become available.
Allen presented a formula for the rate of genetic gain, saying it equals (variation x accuracy x selection intensity) divided by the genetic interval. Accuracy and intensity of selection have increased significantly with the use of genomic predictions, AI, embryo transfer and sexed semen. In-vitro fertilization meanwhile, has reduced the genetic interval by allowing production of multiple calves per year from elite cows, and production of embryos from elite heifers as early as six months of age.
Allen says his company uses these technologies to qualify donor cattle using high-density genomic chips, collect ova from juvenile donors, conduct in-vitro fertilization using sexed semen and gestate all the resulting embryos in recipient animals.
The company also engages in cloning of elite beef and dairy cattle through its Viagen division. Cloning, Allen says, can provide a valuable alternative in multiple situations. These include:
- Greatly expand the reproductive potential of top animals.
- Keep up with demand for their semen, embryos and offspring.
- Preserve genes as insurance against unexpected injury or loss.
- Quickly improve quality and consistency within a herd.
- Expand marketing opportunities.
He cites an example of an outstanding Holstein bull with the pedigree and genomic numbers to serve as an elite AI stud. The bull, however, suffered from severe respiratory disease as a calf, which limited its performance. Its clone, however, sold over 100,000 units of semen into the dairy market.
Biotechnology applications in livestock also hold tremendous promise for food production and medicine, Allen says. Transchromosomic cows, for example, can be designed to produce human polyclonal antibodies. Pigs can be modified for use as medical models, speeding research into critical human diseases, and potentially producing human organs for transplant. Scientists have made progress toward introducing mastitis resistance in cattle, influenza resistance in swine and even BSE resistance in cattle. Much of the work, however, and commercial introduction of these technologies, has been slowed or stagnated due to an excess of caution on the part of activist groups and regulators.