Janssen Animal Health has released the results of a survey which suggests incorrect worming strategies on many pig units in the UK are costing the industry dearly.
Most state they do not worm weaners, growers or finishing pigs at all and, while most sows are wormed, only a third treat newly-arrived gilts and boars in quarantine.
Phil Macdonald, UK and Ireland pig business manager at Janssen said: "Worm infestations can harm growth rate and feed efficiency, they can reduce abattoir returns and increase the cost of medication".
According to the company, the survey responses point to confusion among some producers on what constitutes a strategic worming programme. Most, 68 per cent, state they have implemented strategic programmes, but fewer than two-thirds of these cover all pigs on a unit and even fewer correctly base their programmes on the pre-patent period of worms.
Phil said: "It's important that all pigs on a unit are covered by the programme, otherwise there is a higher potential for reinfection. To be effective, the anthelmintic treatment periods need to be based on the pre-patent period of worms, so that treatment interrupts their life cycle.
"It requires a strategic worming programme with a broad spectrum anthelmintic such as Flubenol and Solubenol 100mg/g, which is the first and only water-soluble benzimidazole in the market. These are effective against larvae and worm eggs of a number of worm species as well as the large roundworm, Ascaris suum. Migrating larvae of the large roundworm cause Milk Spot lesions in pig livers, which are damaging to animal welfare and unit economics."
The make-up of UK units in the survey was 58 per cent breeder/finisher, 39 per cent finisher, 3 per cent weaner/finisher. Most, 68 per cent, use dry pelleted feed, 16 per cent wet feed and 16 per cent have both feed systems.
There is wide variation in worming programmes among producers. Most breeders worm their sows - 17 per cent once a year, 56 per cent twice and 11 per cent three times. With boars, 28 per cent worm them once a year, 44 per cent twice and 11 per cent three times. But only one-third (34 per cent) of breeders worm newly-arrived gilts and boars in quarantine.
72 per cent of producers with breeding sows who responded do not worm weaners and 80 per cent do not worm growers. Of the total responses, including specialist finishers, 68 per cent do not worm finishing pigs.
Most producers, 81 per cent, stated that they are aware that livers with Milk Spot lesions have to be trimmed or totally condemned, adding significant annual costs for disposal.
68 per cent admit to Milk Spot lesion levels of 25 per cent in consignments of pigs. Another 10 per cent experience up to 75 per cent livers with Milk Spot damage, and 3 per cent have had every pig liver in a consignment trimmed or condemned because of lesions. The feedback to producers comes from the BPEX Pig Health Scheme, of which 88 per cent of producers are members.
Only 58 per cent of producers are aware that more traditional worming methods allow pigs continuously to reinfect each other and their environment. Traditional programmes do not take the worm's life cycle into account.
The detrimental effect of worm damage that causes most concern to producers is lost growth/poorer feed conversion (29 per cent). Others considered the most important to be:
Phil says research shows that losses in daily liveweight gain alone add up to £2.31 per slaughter pig where liver condemnations are 30 per cent. "The frightening fact is that the loss is for every slaughter pig, not just those with Milk Spot lesions.
"In a 300-sow herd producing 23 pigs per sow per year that's a loss of £15,939 a year. On a 1,000-sow unit that exceeds a horrendous £53,000 annually, and these figures take no account of other areas of loss mentioned."
An adult female worm can shed hundreds of thousands of eggs each day, which pigs pass out in their dung. Worm eggs can remain infective for up to 10 years. Other pigs ingest them and the reinfection process begins.
Phil said: "A strategic worming programme that treats all pigs on a unit simultaneously is the only effective way to almost completely eliminate the problem. The survey has shown there is considerable potential for a large proportion of producers to improve productivity and cut costs by focusing on this critical area of management."
PS: Whilst you're here, take a moment to see our latest job opportunities for vets.