Motility and Fertility during Post-Thawing Storage of Bovine Spermatozoa Frozen Concentrated, Thawed, and Re-Extended
1962; Elsevier BV; Volume: 45; Issue: 10 Linguagem: Inglês
10.3168/jds.s0022-0302(62)89603-9
ISSN1529-9066
Autores Tópico(s)Sperm and Testicular Function
ResumoTwenty ejaculates of semen from 17 dairy bulls were extended to contain 200 × 10 and 20 × 106 sperm per milliliter in yolk citrate and whole milk extenders and frozen with 7% glycerol.The semen frozen with 200 × 106 sperm per milliliter was re-extended, after thawing, to 20 × 106 sperm per milliliter in yolk citrate, whole milk, skimmilk, and CUE, and the motility of these semen samples was estimated during 72 hr of storage at 5 C.Freezing semen with 200 × 106 sperm per milliliter resulted in significantly improved motilities (P<.01), particularly as the storage interval increased (P<.01).The four re-extension extenders differed in their ability to maintain motility (P<.01), particularly as the storage interval increased (P<.01).In general, sperm survived post-thawing storage much better when re-extended in extenders other than those in which the sperm were frozen.The average 60-to 90-day nonreturn percentages for semen frozen with 200 × 106 sperm per milliliter and re-extended after thawing to 15 × 106 motile sperm per milliliter in yolk-citrate and CUE was 51.8 and 63.0%, respectively, as measured with a total of 2,062 inseminations made between 24 and 60 hr after thawing.The 63.0% for CUE did not significantly differ from the average of 66.5% for control frozen semen thawed immediately before 675 cows were inseminated (P > .05),but both of these values were significantly higher than the 51.8% for the semen re-extended in yolk citrate (P < .05).
Referência(s)