Long term preservation of stallion semen
S.M. ROMBE, V.A. KOTYAGINA
Dyvovo, Institut National d'Elevage des Chevaux

After centrifugation, spermatozoa were suspended in
the following diluter : lactose 11g ; ethylene glycol 4.5 ml
or glycerol 3.5.ml ; egg yolk 0.8 g ; streptomycin 0.125 g ;
penicillin 300,000 I.U. ; distilled water 100 ml. Diluted
semen was cooled at 3-4°C in 3-4 hours. Freezing was obtai-
ned by dropping on a block of dry ice. After thawing, the
semen was maintaéned at 5-7°C. 20-25 ml of semen, contai-
ning 0.8-1.2x 10”progressively motile sperms were insemi-

nated no longer than 12 hours before ovulation. With frozen
semen preserved 12 hours to 168 days, 26 pregnancies resul-
ted from 43 mares inseminated during the breeding season.