Qualitative ultrastructural changes and morphometry of deccani sheep spermatozoa preserved with egg yolk citrate extender

Abstract

The present investigation was aimed to study the sequential changes in the sperm cell deterioration dur-ing liquid storage of Deccani sheep breed semen from dilution to 48 h of storage along with its seminal characteris-tics and sperm morphometric measurement. Thus the two Deccani adult rams (aged 2 years), were selected (six ejaculates/each ram) and the collected semen was diluted with Egg yolk citrate extender (EYC) (final concentration - 400 million spermatozoa/0.2 ml semen).Seminal characteristics were assessed along with sperm morphologi-cal changes by Electron microscopy immediately after dilution, at 24 and 48 h of storage, respectively. Sperm morphometry was analysed by Image analysis.The percentage of Individual motility, Live spermatozoa, Acrosomal integrity and Hos-test reactive sperm decreased significantly (P<0.05) from 80.41 to 49.16%, 82.75 to 51.25%, 94.16 to 83% and 76 to 48.58%, respectively during liquid storage of semen from initial dilution to 48 h of storage. The sperm head length (?m), Head width, sperm head area (?m2), sperm head perimeter (?m), mid piece length (?m), proximal mid piece width (?m), distal midpiece width (?m), volume of mid piece (?m3) and acrosomal cap length (?m) were 7.80, 4.33, 26.84, 20.63, 14.03, 0.74, 0.51, 4.54 and 5.24, respectively. Electron microscopic qualitative evaluation revealed that the main site of injury is the apical ridge of ram spermatozoa when stored at 5ºC. The electron density of the mitochondria reduced indicating concomittant depletion of ATP and loss of motility resulting in reduction of fertility.