Abstract

In a field trial, 633 ewes from 24 farms were inseminated vaginally using liquid semen (150 x 106 per dose) collected from 15 rams. The semen was either diluted with a milk-based extender (M), filled in 0.2 ml straws and stored for 12 or 24 h (M12, M24) or diluted with M but with the addition of gelatine, filled in 0.5 ml straws and stored for 12 or 24 h (G12, G24). The hypothesis was that a larger volume and the addition of gelatine would prolong the survival of the spermatozoa. The ewes, aged between 6 months and 5.5 years, were allocated into four groups and inseminated after natural oestrus by the farmers themselves with a dose of 150 x 106 spermatozoa. Inseminations in the groups (M12, M24, G12, G24) resulted in lambing rates of 69.6%, 63.6%, 69.4% and 58.3% (overall 65.2%), respectively. Farmer (p < .0002) had a significant effect on the lambing rate, while ram, age of the ewe and dilution rate/addition of gelatine/storage time had not. A pair-wise comparison of the lambing rates between the four groups showed that significant lower results were only achieved for G24 compared with M12. None of the other comparisons showed significant differences. In conclusion, a higher dilution rate of the AI-dose together with the addition of gelatine to the semen extender did not lead to improved fertility results after storage for 24 h when compared with standard AI-doses used in Norway.

Published in

Reproduction in Domestic Animals
2010, Volume: 45, number: 4, pages: 706-710
Publisher: WILEY-BLACKWELL

SLU Authors

• Söderquist, Lennart

  • Department of Clinical Sciences, Swedish University of Agricultural Sciences
    

UKÄ Subject classification

Veterinary Science
Animal and Dairy Science


Publication identifier

DOI: https://doi.org/10.1111/j.1439-0531.2008.01338.x

Permanent link to this page (URI)

https://res.slu.se/id/publ/60834