Artificial insemination (AI) plays a key role in the genetic management of elephants in zoos. Since freshly extended semen is typically used for AI in elephants, it has become imperative to optimize conditions for liquid storage and semen transport. The objectives of this study were to examine the interactions between different extenders and storage temperatures on sperm total motility (%tMOT), progressive motility (%pMOT), and acrosomal integrity (%INT) in Asian (Elephas maximus) and African (Loxodonta africana) elephants. Ejaculates were collected by rectal massage, diluted using a split-sample technique in five semen extenders TL-Hepes (HEP), Modena (MOD), Biladyl (BIL), TEST Refrigeration Medium (TES), and INRA96 (INR), maintained at 35{degrees}C, 22{degrees}C, or 4{degrees}C. At 0, 4, 6, 12, and 24 h, aliquots were removed and assessed for %tMOT, %pMOT, and %INT. After 24 h of storage, African elephant spermatozoa exhibited greater longevity and higher values in sperm quality parameters compared to Asian elephants. In both species, semen storage at 35{degrees}C resulted in a sharp decline in all sperm quality parameters after 4 h of storage, while storage at 22{degrees}C and 4{degrees}C facilitated sperm survival. In Asian elephants, MOD and HEP were most detrimental, while BIL, TES, and INR maintained motility up to 12 h when spermatozoa were cooled to 22{degrees}C or 4{degrees}C. In African elephants, there were no differences among extenders. All media maintained good sperm quality parameters at 22{degrees}C or 4{degrees}C. However, while MOD, BIL, and INR were most effective at lower temperatures, HEP and TES maintained sperm motility at all storage temperatures. This study demonstrates sperm sensitivity to components of various semen extenders and storage temperatures and offers recommendations for semen extender choices for liquid semen storage for both Asian and African elephants.
