Protein map of swine seminal plasma developed

UN/DICYT Although domestic swine seminal plasma (a semen fraction) proteins had already been identified, a map of some of these proteins had not been yet produced. A UNal zootechnician obtained a protein map. The project developed was part of the doctorate thesis work of Verónica González Cardona, a UNal alumnus who has recently returned to Colombia after completing her graduate work in Brazil.

“I traveled to Brazil with a group specialized in proteomics –which is the study of proteins of a determined tissue– as we worked with reproduction fluids, in this specific case male ejaculation fluids, ” said González.

According to González she was looking to do something new and see what could come of this, “I wanted to find proteins which could be useful as molecular markers, in other words ones which I could identify if the animal had certain proteins and if they were good breeders or not, ” she said.

Although there are other forms to assess fertility levels in swine, this method is obtained in a more specific manner and takes eight days to produce a protein map.

González used a method known as 2D electrophoresis which separates proteins in two stages.

In the first stage, gel is adhered to a plastic or acetate strip where proteins are placed (seminal plasma) and they are separated due to their isoelectric point or pH. During the second stage proteins are separated due to their molecular weight, therefore providing a protein dimensional depiction.

By using this method they associated aspects such as vigor, motility and vitality as well as sperm cell morphology.

The importance of achieving this lies in that swine semen is one of the most difficult to cryopreserve. Bovine semen, for instance can be frozen and stored for years; it can be used without cells having significant damage.

Instead swine, horse and other species semen is hard to store and have in a germoplasm bank for several years.

“It’s small progress but could be used to find a way of maintaining these cells stable for a long time, maybe with one of these proteins, ” she said.