Innovations in Reproductive and Cryopreservation Technologies in Pigs and Cattle

Embryo cryopreservation

Embryo cryopreservation is the process of freezing and storing embryos for future use. It is often part of in vitro fertilization (IVF) programs. There are two types of embryo freezing procedures:

1. Slow-freezing: a method that involves the formation of extracellular ice
2: Vitrification: a method where the embryos are cooled very rapidly so that the water molecules in the embryos don’t have time to crystallize

Bovine and swine embryos

Although the current standard methods for vitrification of embryos in the bovine breeding industry give good results with biopsied embryos, the procedure is very complicated and labour-intensive. On the opposite, the slow freezing method is easy to apply, but the survival rate of biopsied embryos is poor. In addition, the technology for cryopreservation of swine embryos is some years behind in comparison to the technology in the bovine breeding industry.

Together with our partners Topigs Norsvin and CRV, we aim to develop a usable and efficient direct transfer vitrification protocol for both bovine and swine industries. We will also investigate how non-invasive methods for quality assessment of embryos – for example time-lapse imaging (TLI) – can be applied as a measure of quality for pig and cattle embryos, especially in evaluating conditions and protocols of embryo vitrification.

We will use a mathematical model to simulate vitrification, followed by dedicated laboratory vitrification experiments (non-direct and direct transfer vitrification method for in vivo and in vitro derived swine embryos, and direct transfer vitrification methods for bovine in vitro produced biopsied and non-biopsied embryos). Subsequently, selected vitrification protocols will be tested empirically, and the protocols that appear successful in the lab will be tested in a small field trial.

Breeding for sustainable livestock farming

This research ties in well with the goals of livestock breeding companies to move into the future of sustainability and achieve climate neutral and circular animal production. The extensive application of embryos produced in vitro or in vivo, combined with genomic testing, is a powerful and valuable tool that can make a major contribution to increase genetic progress in important traits related to efficiency, health and resilience. Moreover, this research focuses on reproductive technologies that are also needed to preserve genetic diversity and (rare) breeds, which means that both breeding companies and the national gene bank (CGN) will benefit from our advances.