Home⇛Annals of Tropical Research⇛vol. 48 no. 1 (2026)

Advancing Boar Sperm Cryopreservation in the Philippines: Essentials, Expectations, and Economics

Santiago T. Peña, Jr.

 

Abstract:

The application of frozen–thawed semen (FTS) in swine reproduction remains limited despite the proven success of artificial insemination (AI) with fresh extended semen (FES). Boar spermatozoa are particularly susceptible to cryopreservationinduced damage owing to their high polyunsaturated fatty acid content and limited antioxidant capacity in the seminal plasma, resulting in substantial cryoinjury during freezing and thawing. These lead to reduced motility, membrane integrity, mitochondrial function, and DNA integrity, thus limiting fertility outcomes. This review synthesizes current knowledge on boar semen cryopreservation, highlighting key factors that influence postthaw quality, including ejaculate selection, extender composition, cryoprotectant type and concentrations, cooling and thawing rates, packaging methods, and post-thaw handling practices. Recent studies demonstrate that innovations such as antioxidant supplementation, optimized extender systems, and refined freezing protocols can substantially improve post-thaw sperm viability, with significantly improved farrowing rates and litter sizes. Beyond immediate fertility benefits, FTS enables long-term storage, facilitates transboundary genetic exchange, reduces dependence on live boar transport, and supports conservation of native pig populations and elite germplasm. In the Philippines, the sustained effects of African Swine Fever and other disease outbreaks have severely disrupted the swine industry, elevating the relevance of semen cryopreservation as a biotechnological strategy to enhance herd resilience and safeguard genetic diversity. Although economic and technical challenges remain, continued methodological advancements and field validation suggest that FTS has the potential to serve as a reliable, flexible, and sustainable reproductive tool to improve reproductive efficiency, support genetic improvement, and strengthen both commercial and native swine production.



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