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Traversing the ovine cervix – a challenge for cryopreserved semen and creative science

Published online by Cambridge University Press:  22 June 2011

J. J. Robinson ,
W. A. C. McKelvey ,
M. E. King ,
S. E. Mitchell ,
M. J. A. Mylne ,
T. G. McEvoy ,
W. S. Dingwall  and
L. M. Williams
J. J. Robinson*
Affiliation:
Animal Biology Division, Scottish Agricultural College, Ferguson Building, Craibstone Estate, Bucksburn, Aberdeen AB21 9YA, UK
W. A. C. McKelvey
Affiliation:
Animal Health Research Group, Scottish Agricultural College, Kings Buildings, West Mains Road, Edinburgh EH9 3JG, Scotland, UK
M. E. King
Affiliation:
Animal Biology Division, Scottish Agricultural College, Ferguson Building, Craibstone Estate, Bucksburn, Aberdeen AB21 9YA, UK
S. E. Mitchell
Affiliation:
Integrative Physiology, Institute of Environmental and Biological Sciences, University of Aberdeen, Aberdeen AB24 2TZ, UK
M. J. A. Mylne
Affiliation:
East Mains, Ormiston, East Lothian EH35 5NG, UK
T. G. McEvoy
Affiliation:
Animal Health Research Group, Scottish Agricultural College, Kings Buildings, West Mains Road, Edinburgh EH9 3JG, Scotland, UK
W. S. Dingwall
Affiliation:
Animal Health Research Group, Scottish Agricultural College, Kings Buildings, West Mains Road, Edinburgh EH9 3JG, Scotland, UK
L. M. Williams
Affiliation:
Molecular Nutrition Group, Rowett Institute of Nutrition and Health, University of Aberdeen, Bucksburn, Aberdeen AB21 9SB, Scotland, UK
*
†E-mail: john.robinson@sac.ac.uk
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Abstract

This review brings together research findings on cervical relaxation in the ewe and its pharmacological stimulation for enhancement of the penetration needed for transcervical insemination and embryo transfer. On the basis that the success of artificial insemination is the percentage of ewes lambing, a review is made of recent research aimed at understanding and minimising the sub-lethal effects of freezing and thawing on the viability of spermatozoa, their membrane integrity and their ability to migrate through cervical mucus, as these characteristics have a major influence on fertility, particularly when semen is deposited, artificially, in the os cervix. Milestones of achievement are given for transcervical intrauterine insemination, embryo recovery and transfer and the birth of lambs of pre-determined sex, firstly following intracytoplasmic sperm injection, then laparoscopic intrauterine insemination using highly diluted flow-cytometrically sorted fresh semen and subsequently by os cervix insemination using sexed semen that had been frozen and thawed. Diversity of research endeavour (applied, cellular, molecular), research discipline (anatomy, histology, immunology, endocrinology) and research focus (cell, tissue, organ, whole animal) is embraced within the review as each has significant contributions to make in advancing recent scientific findings from the laboratory into robust on-farm transcervical insemination and embryo transfer techniques.

Keywords

ovine cervixsemen cryopreservationartificial inseminationembryo recovery and transfer
Type
Full Paper
Information
animal , Volume 5 , Issue 11 , 26 September 2011 , pp. 1791 - 1804
Copyright
Copyright © The Animal Consortium 2011

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