Combinations of Glycerol Percent, Glycerol Equilibration Time, and Thawing Rate Upon Freezability of Bull Spermatozoa in Plastic Straws

Effect of rates of freezing, thawing and level of glycerol on the survival of bovine spermatozoa in straws.

Extended semen from six Hereford bulls was placed in .25-ml Continental straws and frozen in the vertical position. Treatments were arranged factorially with glycerol levels of 5, 7, 9 or 11%; semen cooled from 5 to 1 3 0 C in 3.5 (fast), 20 (moderate) or 40 min (slow); and thawed in water at 5 C for 3 min, 35 C for 12 sec, 55 C for 8 sec, 75 C for 7 sec or 90 C for 5 seconds. Fast freezing res...

The immobilization of spermatozoa by freezing and thawing and the protective action of glycerol.

It was discovered by Polge, Smith & Parkes (1949) that spermatozoa could be frozen and thawed without loss of motility if glycerol was included in their suspending medium. Following this discovery the spermatozoa of the domestic fowl (Polge, 1951), ofthe bull (Polge & Rowson, 1952) and ofthe herring (Blaxter, 1953) have been preserved without loss of function for long periods in the frozen stat...

P-137: Effect of Different Equilibration, Freezing and Thawing Rate on Cryopreserved Buffalo Spermatozoa Diluted inTris- Egg Yolk Extender

Background: Artificial insemination (AI) has been used for increasing genetic potential of animals in production while application of AI has been restricted in buffalo due to low freezing ability and fertility of frozen-thawed buffalo spermatozoa. So improvement in buffalo sperm cryopreservation may enhance the breeding programs of this valuable farm animal. Semen processing is one of the major...

Evaluation of Serial Thawing-Refreezing on Human Spermatozoa Resistance Using Cryovials and Straws

Influence of freeze rate, thaw rate and glycerol level on acrosomal retention and survival of bovine spermatozoa frozen in French straws.

A three-dimensional central composite design was used to study the effect of glycerol level, freeze rate, and thaw rate on acrosomal retention and percent motility. Glycerol levels examined were: 1, 4, 7, 10 and 13%. Average freeze rates between 1 0 and 8 0 C examined were: 6.5, 13.1, 26.3, 52.5 and 105.0 C/minute. Thaw rates studied were achieved by plunging straws into water at 5 C for 2 rain...