Intrauterine insemination of sows by using a two-chamber semen bag system.

Artificial insemination of sows is an effective method for intensive use of high breeding value boars. In sows, intracervical insemination (ICI) using 2 to 3 billion spermatozoa is an established method worldwide, resulting in aconsistently high fertility (Watson et al. 2002). Using intrauterine insemination, the number of spermatozoa per insemination can be reduced even further. In intrauterine insemination (IUI), the tip of the catheter is placed in the corpus uteri depositing the semen even closer to the site of fertilization in the oviduct (Vazquez et a/. 2008). If IUI can be performed aseasily and efficiently as ICI, this will result in more semen doses per boar. This will allow a stronger selection among boars, and lower the costs per dose. This study investigated the effect on fertility, when reducing the amount of sperm per dose using IUI. A total of 9272 multiparous Danish Landrace x Large White crossbred sows from seven Danish commercial herds were randomly distributed into three groups as shown in table 1. All sows were inseminated using heterospermic semen from Danish Duroc boars. Semen was collected using the gloved hand method collecting the whole ejaculate. Semen quality was evaluated using subjective microscopic motility score. Semen concentration was measured using NucleoCounter SP100. Semen was extended using EDTA boar semen extender. The same batch of semen comprising semen from 6 to 10 boars was used in all three groups in each herd. One dose from each batch was analysed for content of sperm per dose using SP100.