Effect of supplementation of valine to chicken extender on sperm cryoresistance and post-thaw fertilization capacity

A paper produced in the frame of the H2020 project 677353 'Innovative Management of Animal GEnetic resources' The present study evaluated the effect of supplementing valine to semen extender for freezing sperm of 2 endangered local Spanish chicken breeds with different sperm cryoresistance. The evaluation of the samples before and after freezing-thawing included motility (CASA-Mot system), viability, DNA integrity, and fertility rate. The results showed that supplementation of valine to chicken freezing extenders shows a positive effect on DNA fragmentation and fertilizing ability of frozen–thawed sperm, with a better response in a breed considered as the lowest freezer in our conservatory.Part of this research was funded by Zoitechlab S.L.-INIA contract CON 18-141, and INIA project RZP2015-0002-00-00. This paper is dedicated to the memory of our dear coworker, Dr. Serafín Perez Cerezales, who recently passed-away