Motility and Fertility of Bull Sperm Frozen-Thawed Differently in Egg Yolk and Milk Extenders Containing Detergent

The purpose of this study was to examine survival and fertility of frozen bull sperm processed in several extenders containing a detergent mixture, sodium, and triethanolamine lauryl sulfate. Addition of .5% (vol/vol) detergent to whole milk was completely spermicidal. When 10% egg yolk (vol/vol) was included in the glycerol or nonglycerol fractions or both fractions of milk, sperm were equally well preserved in the presence of .5% detergent, and sperm survival following thawing at 4 degrees C was dramatically improved by the detergent. This improved result with the 4 degrees C thaw temperature also was obtained by adding .5% detergent to an egg yolk-Tris extender. Thawing temperatures of 30 and 50 degrees C (later for 15 s) were generally superior to 4 degrees C. A fertility trial with whole milk, whole milk-10% yolk, whole milk-10% yolk-.5% detergent, egg yolk-Tris, and egg yolk-Tris-.5% detergent was conducted. The 59-d percent nonreturns, respectively, were 73.4, 65.8, 65.6, 69.5, and 73.4. Whole milk or egg yolk-Tris plus detergent were equally superior to the other extenders for bull semen.