EFFECTS OF SEMEN COLLECTION INTERVAL ON FRESH AND FROZEN SEMEN PARAMETERS IN TUSHIN RAMS

摘要

Ejaculates from three rams were collected with artificial vagina at one day (OD1) and four day intervals (FDsI). Part of the semen samples were pooled, diluted with skim milk based extender: -egg yolk (10%) -glycerol (5%), loaded into 0.25 ml straws,equilibrated, frozen, and afterwards stored in liquid nitrogen. The following spermatozoon parameters were determined in fresh and frozen-thawed semen: motility, viability, abnormality, abnormal acrosome, and membrane integrity. Semen collected at ODI had significantly higher freeze-ability compared with semen collected at FDsI for spermatozoon motility. Frozen-thawed semen collected at ODI had higher viability and membrane integrity, and lower abnormality and abnormal acrosome percentages compared withFDsI. It was concluded that in order to use cryopreservation of the Tushin ram semen, ODI instead of FDsI collection should be preferred.