Early pregnancy loss in sows after low dose, deep uterine artificial insemination with sex-sorted, frozen-thawed sperm.
Recent developments in reproductive technologies have enabled the production of piglets of a predetermined sex via non-surgical, low dose artificial insemination. The practical application of sex-sorting technology to the pig is made challenging by the large numbers of sperm required for successful insemination of sows. One way of overcoming the time required for sex-sorting may be to create a bank of cryopreserved, sex-sorted sperm, thus making available appropriate doses as sows require insemination. To date, little success has been achieved with non-surgical inseminations of sex-sorted boar sperm. This study attempted to achieve litters of a predetermined sex after a double insemination of sows with 160x10(6) sex-sorted, frozen-thawed sperm. Sows were synchronised and sperm were non-surgically inseminated into the proximal third of the uterine horn at 36 and 42 h after hCG administration. Sows inseminated with sex-sorted sperm achieved similar pregnancy rates to those receiving an equal dose of unsorted, frozen-thawed sperm. However, all sows conceiving after insemination with sex-sorted sperm returned to oestrus within 57 days of insemination. This was a higher rate of pregnancy loss than observed for sows inseminated with unsorted sperm (37.5%; P=0.031). A combination of low sperm numbers and potentially compromised developmental capability of embryos derived from sex-sorted sperm may have resulted in this early stage loss of pregnancy.
Bathgate
R
R
Centre for Advanced Technologies in Animal Genetics and Reproduction (ReproGen), Faculty of Veterinary Science, The University of Sydney, NSW 2006, Australia. roslynb@vetsci.usyd.edu.au
Grossfeld
R
R
Susetio
D
D
Ruckholdt
M
M
Heasman
K
K
Rath
D
D
Evans
G
G
Maxwell
W M C
WM
D000034:Abortion, Veterinary; D000818:Animals; D015925:Cryopreservation / Q000662:veterinary; D005260:Female; D005434:Flow Cytometry / Q000662:veterinary; D007315:Insemination, Artificial / Q000379:methods / Q000662:veterinary*; D008297:Male; D011247:Pregnancy; D012662:Semen Preservation / Q000662:veterinary; D012743:Sex Preselection / Q000379:methods / Q000662:veterinary*; D013094:Spermatozoa / Q000502:physiology*; D013552:Swine / Q000502:physiology*