Chicken semen cryopreservation: importance of cryoprotectants

SUMMARY

Sperm cryopreservation is an important strategy to conserve animal genetic diversity and transmit superior genetic background, facilitated by a non-invasive sampling and collection of large amounts of sperm. In chickens, various freezing protocols and cryoprotectants (CPAs) have been developed to freeze sperm, but each lab still debates and competes to disclose the most suitable freezing conditions. Many key points, such as semen donor selection, collection tips, diluent compositions, CPA selection, pre-freezing manipulation, semen packaging type, freezing and thawing rates, are all impactful to the efficiency of chicken sperm cryopreservation. Whereas glycerol is believed as the most efficient and the less toxic CPA, it also presents an unwanted contraceptive effect after insemination. Thus, one of the major developed strategies to conquer this issue is removing glycerol before insemination, but current protocols remain not efficient to completely abolish glycerol contraceptive effect. Novel methodologies will bring us a better understanding of the cellular and molecular mechanisms involved in sperm cryobiology to decipher the challenges of chicken sperm cryopreservation.

KEYWORDS:

• Chicken
• semen
• freezing
• cryoprotectant
• glycerol
• contraception

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the French National Infrastructure of Research CRB anim funded by ‘Investissements d’avenir’, Agence Nationale de la Recherche [ANR-11- INBS-0003] and from the French National Institute of Agronomic and Environmental Research (INRAe).

Notes on contributors

Hsiu-Lien Herbie Lin

Hsiu-Lien Herbie Lin works for the projects on sperm quality evaluation and cryopreservation of chickens and pigs at Taiwan Livestock Research Institute since 2007. Now she is doing her PhD study in INRAE, France since September 2019. Her study subjects mainly focus on improving chicken sperm cryopreservation and exploring the impacts of cryoprotectants on chicken sperm physiology.

Elisabeth Blesbois

Dr. Elisabeth Blesbois is a French scientist that developed researches in Reproductive Biology and Cryobanking. Her main publications are in the field of animal reproductive cells biology and their applications to the improvements of management of genetic diversity and breeding practice. She coordinated a number of national and international programs in this field. She has led several research teams, was a member of the Board of Directors of the French Institute of Agronomic Research and of the High Council of Biotechnology.

Anaïs Vitorino Carvalho

Anaïs Vitorino Carvalho After investigating the regulation of various endometrial factors during implantation and the impact of embryo microenvironment on the early development in cattle, Anaïs Vitorino Carvalho started to explore bird physiology, in 2017, by investigating the epigenetic mechanisms involved in the long-term impact and transgenerational inheritance of embryonic environment perturbations in quails. Since 2019, she has focused her work on the better understanding of the mechanisms of chicken sperm fertilizing capacity.