Fertility of frozen chicken semen after intravaginal and intrauterine inseminations using various concentrations and equilibration times of dimethylsulfoxide and a range of freezing and thawing rates.

The use of dimethyl sulfoxide (DMSO) as a cryoprotective agent for freezing chicken semen was examined with respect to intravaginal (I.V.) and intrauterine(I.U.) inseminations. Semen diluted in DMSO was subjected to various freeze rates, equilibration times and thawing rates. Various concentrations of DMSO were examined as was the effect of diluting DMSO with phosphate buffer and Lake's solution. There was no significant (p greater than 0.05) effect of rate of freeze (ranging from 1.3 degrees C to 7.2 degrees C. per min) on fertility. However, rapid thawing in an ice bath resulted in a longer (p less than 0.05) duration of fertility than thawing at 1 degree C. per min., but had no effect on percent fertility during duration or percent hens fertile. Equilibration time and concentration of DMSO had no significant (p greater than 0.05) effects on fertility. There was no interaction between insemination route and Lake's solution vs. phosphate buffer with respect to duration of fertility. It was concluded that intrauterine (I.U.) insemination resulted in superior fertility to intravaginal (I.V.) inseminations with semen frozen in DMSO.