At least 80 per cent of the sow herd in Northern Ireland is artificially inseminated. The traditional method of insemination involves the use of a sponge catheter, which delivers semen into the cervix of the sow. Sows are normally inseminated twice within each heat to ensure a successful conception. Recently, a new type of catheter was introduced – the Deep Intrauterine (DIU) catheter – which delivers the semen into the uterine horn and closer to the egg. Manufacturers claim that only one insemination is required using this catheter to achieve conception. However, success would greatly depend on accurate and timely heat detection and subsequent insemination.

A trial conducted at AFBI compared the use of the DIU catheter with the traditional catheter and insemination regime. The trial was conducted on the sow herd at the AFBI Hillsborough, and was co-funded by Pig ReGen Ltd and DARD.

In total, 180 sows were used and three insemination procedures were compared:

AFBI Hillsborough investigates the use of deep intrauterine insemination for sows.

• 'Normal' – Sows were inseminated twice using a normal catheter. If heat was detected at 8am, the first insemination took place two to three hours later and the second, 24 to 26 hrs after detection. If sows were detected in heat at 4pm, the insemination took place at 8am the following morning and the second one 24 hours later.
  
  
• 'DIU + Normal' – After detection, sows were inseminated in the same pattern as above. In this treatment, a DIU catheter was used in the first insemination and a normal catheter was used in the second insemination.
  
  
• 'DIU Once' – After detection as described above, sows were inseminated once using a deep intrauterine catheter 24 hours after detection.

In this study, the lowest conception rate (72 per cent) and lowest number of pigs born alive (11.1) were the result of inseminating sows with the DIU catheter once 24 hours after heat was detected (Table 1). Under normal commercial management where sows are inspected for heat and inseminated within time blocks, it is difficult to ensure high success rates using the 'once' method.

However, the combination of the DIU catheter with a normal catheter within a 'twice' insemination procedure optimised conception rates (88 per cent) and the number of pigs born alive (12.1), with little effect on the average birth weight of piglets born. As expected, as the number of pigs born increased, the average birth weight of pigs decreased. However, in this case the difference was not excessive.

If the DIU catheter was to be used on farm, specialised training is required as incorrect use can damage the reproductive tract within the sow. A high standard of hygiene should also be in place since the insertion of a dirty catheter would deliver infection deep into the reproductive organs of the sow.

February 2010