Preservation and artificial insemination of sexed semen in sheep
G. Evans A B , F. K. Hollinshead A and W. M. C. Maxwell A
+ Author Affiliations
- Author Affiliations
A Centre for Advanced Technologies in Animal Genetics and Reproduction, Faculty of Veterinary Science, The University of Sydney, NSW 2006, Australia.
B To whom correspondence should be addressed. email: garethe@vetsci.usyd.edu.au
Reproduction, Fertility and Development 16(4) 455-464 https://doi.org/10.1071/RD04032
Accepted: 23 March 2004 Published: 6 July 2004
Abstract
Sperm-sexing technology using flow cytometry is in advanced stages of development for the sperm of several species. The sorting process could compromise sperm viability and sperm require specific handling procedures both before and after sorting to maintain the integrity and function of the sorted sperm. Standard freezing protocols have been modified for post-sorting cryopreservation of sperm and frozen sperm have been successfully thawed, sorted, refrozen and subsequently used to produce offspring. The relatively low numbers of available sorted sperm have, in some cases, led to modification of artificial insemination techniques to maximise efficiency of use. Multiple ovulation and embryo transfer, or in vitro fertilisation and associated technology, may lead to the more efficient use of sexed sperm.
Extra keywords: cryopreservation, sperm sorting.
References
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