Trichinella Update

12 June 1997

The number of pigs that have been confirmed to have the parasite Trichinella spiralis now stands at 4. All four are sows from the original Mamaku farm where asingle case of the parasite was confirmed late last month. 23 other younger porkers and suckling pigs from the property have tested negative for the parasite.

The pigs were slaughtered, under MAF supervision, at a licensed premises and samples were sent for testing to the MAF Ruakura Animal Health Laboratory. Confirmations were carried out at the MAF Batchelor Animal Health Laboratory in Palmerston North.

All test positive carcasses have been condemned, and will be destroyed. Test negative carcasses (i.e. free of the parasite) will be further processed by either heat or cold treatment as an added assurance.

The property in question, which was a small scale backyard operation, has now been totally destocked of pigs and its restricted place notice has been lifted. Trapping of rats, which are considered to be the most likely vectors of the parasite, began on 4 June 1997 and will be carried out for 10 days, at which stage the results will be assessed and a decision made on appropriate follow up action. Investigations into whether the original sale constituted an illegal sale of uninspected meat are progressing independently.

Two other properties were identified by MAF as having been supplied with weaners (approximately 6-8 weeks old) from the affected property in the last month. Both properties were issued restricted place notices.

One notice has subsequently been removed following the owner volunteering to destroy all of the weaners purchased. Samples from these weaners have subsequently all tested negative for Trichinella.

The other owner has decided to rear three weaners through to slaughter weight or even beyond. Accordingly, the restricted place notice will remain in place for this property until such time as they are slaughtered.

Following the initial media release, MAF was contacted by another small farm holder of the purchase of a boar from the affected property two months ago. The boar had already been slaughtered and was undergoing processing at their local butchers for their personal consumption. The owners declined the Ministry’s offer to test free of charge samples from the boar, and accordingly have been advised of the potential risks and the measures necessary to ensure food safety.

Modern pig farming practices make it extremely uncommon for Trichinella to find its way into commercial piggeries. Overseas, small scale backyard farm and slaughter operations have tended to be where the parasite has caused problems.

MAF takes this opportunity to remind consumers that as a basic food hygiene principle all pork should be correctly cooked.

Dr Mirzet Sabirovic, National Manager (Exotic Disease Programmes), 04 47 49 809
Dr Bill Jolly, National Manager (Residues), 04 47 44 156



Last Updated: 09 September 2010

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