COOL PRESERVATION OF DILUTED BULL SEMEN COLLECTED THROUGH DELPLETION TRIALS

The present study was carried to investigate the effect of cool preservation on the motility and livability of 7-22 consecutive ejaculates collected through depletion in bulls with variable ages (13 month - 12 years) and breeds (Friesian, Native and
their crosses). Egg yolk citrate, fructose, su glycerol and milk glycine were used as suitable se diluents with no valuable difference. The young
bulls were unable to give more than 7 ejaculates to o per depletion while the aged one reached 22 son collection. There was positive correlation between a
sperm motility and livability among ejaculates 1250 For (r=0.79). With storage at 3-4 C there was
significant reduction in sperm motility and stii Selivability at the 3 day although the results were vie still above 60%. Moreover, samples with higher STEM initial activity irrespective of their situations to in the depletion remained with best motility till
the end of storage (15 days). Samples with otis Tur relatively low initial motility and livability lost
is their activity at the day of storage. There
obtained results might permit the use of Bull semen collected through depletion trials up to 7h day of Storage at + 4°C.