Sperm cryopreservation is a fundamental process for the long-term conservation of livestock genetic resources. Yet, the packaging method has been shown, among other factors, to affect the frozen-thawed (FT) sperm quality. This study aimed to develop a new mini-straw for sperm cryopreservation. In addition, the kinematic patterns, viability, acrosome integrity, and mitochondrial membrane potential (MMP) of boar spermatozoa frozen in the developed 0.25 mL straw, 0.25 mL (minitube, Germany), or 0.5 mL (IMV technologies, France) straws were assessed. Postthaw kinematic parameters were not different (experiment 1: total motility (33.89%, 32.42%), progressive motility (19.13%, 19.09%), curvilinear velocity (42.32, 42.86), and average path velocity (33.40, 33.62) for minitube and the developed straws, respectively. Further, the viability (38.56%, 34.03%), acrosome integrity (53.38%, 48.88%), MMP (42.32%, 36.71%) of spermatozoa frozen using both straw were not differ statistically (p > 0.05). In experiment two, the quality parameters for semen frozen in the developed straw were compared with the 0.5 mL IMV straw. The total motility (41.26%, 39.1%), progressive motility (24.62%, 23.25%), curvilinear velocity (46.44, 48.25), and average path velocity (37.98, 39.12), respectively, for IMV and the developed straw, did not differ statistically. Additionally, there was no significant difference in the viability (39.60%, 33.17%), acrosome integrity (46.23%, 43.23%), and MMP (39.66, 32.51) for IMV and the developed straw, respectively. These results validate the safety and efficiency of the developed straw and highlight its great potential for clinical application. Moreover, both 0.25 mL and 0.5 mL straws fit the present protocol for cryopreservation of boar spermatozoa.

ABSTRACT
INTRODUCTION
MATERIALS AND METHODS
    Experimental design
    Semen collection and sperm cryopreservation
    Evaluation of post-thaw motility and kinematicparameters
    Evaluation of post-thaw viability
    Evaluation of post-thaw acrosomal integrity
    Evaluation of post-thaw mitochondrial membranepotential (MMP)
    Statistical analysis
RESULTS
    Experiment one
    Experiment two
DISCUSSION
CONCLUSION
REFERENCES

• Areeg Almubarak(Department of Theriogenology and Reproductive Biotechnology, College of Veterinary Medicine and Bio-safety Research Institute, Jeonbuk National University, Department of Veterinary Medicine and Surgery, College of Veterinary Medicine, Sudan University of Science and Technology)
• Rana Osman(Department of Theriogenology and Reproductive Biotechnology, College of Veterinary Medicine and Bio-safety Research Institute, Jeonbuk National University, Iksan 54596, Korea)
• Seongju Lee(Department of Theriogenology and Reproductive Biotechnology, College of Veterinary Medicine and Bio-safety Research Institute, Jeonbuk National University, Iksan 54596, Korea)
• Iljeoung Yu(Department of Theriogenology and Reproductive Biotechnology, College of Veterinary Medicine and Bio-safety Research Institute, Jeonbuk National University, Iksan 54596, Korea)
• Yubyeol Jeon(Department of Theriogenology and Reproductive Biotechnology, College of Veterinary Medicine and Bio-safety Research Institute, Jeonbuk National University, Iksan 54596, Korea) Corresponding Author