Gapeworms hit free range flocks While gamekeepers are constantly on the days the eggs embryonate and are infective crows have played a part in spreading the lookout for an attack of gapeworms in when eaten by other birds. The resulting infection. pheasants and partridges being reared for larvae then migrate from the intestine to the commercial shoots, it is a disease problem trachea and lungs. In the past I’ve opened up shot specimens of that is considered rare in chickens. these birds and they’ve been full of But the eggs can also be picked up by gapeworms so it is quite possible that these But westcountry poultry vet Alan Beynon has earthworms, slugs and snails which provide act as the vector.” recently diagnosed the parasite in free range an intermediate host. Gapeworm larvae can laying birds. remain viable for over four years in All three flocks recovered following treatment earthworms, and around a year in slugs and with the wormer Flubenvet, although this was The gapeworm (Syngamus trachea) is a snails, meaning land can still be infective not before the worst affected flock had round red worm that attaches to the trachea long after it has been free from poultry. dropped to around 65 per cent production at of birds and causes the disease referred to 35 weeks, and suffered significant mortality. as ‘gapes’, so-called because of the open- As well as attending to poultry, vet Alan mouthed breathing characteristics associated Beynon specialises in game bird health and "This just underlines once again the need to with infected birds as illustrated above. is therefore no stranger to gapeworms, worm free range flocks on a regular basis,” Heavily infected birds produce a grunting although until recently he had only ever seen said Mr Beynon. sound and because the worms will eventually one case in chickens. block the trachea, infection can lead to suffocation. "This last month I’ve seen three outbreaks in free range laying flocks, all in the same Male and female gapeworms are in a form of locality,” reports Mr Beynon. permanent copulation and the eggs they produce are coughed up into the bird’s “The three farms involved all border a very throat where most of them are swallowed large commercial shoot so we have to and passed out with the faeces, although suspect this is the original source of some may be expelled directly via the beak or infection, although we cannot be sure how it nostrils. Sometimes whole worms are was transmitted to the free range flocks.” disgorged via the beak. Although it is possible that the gapeworm The lifecycle of the worm starts with the eggs could have been shed by pheasants miniscule eggs which are spread about the and then picked up by the poultry, the vet vicinity of infected birds. Within eight to 14 believes it is equally likely that rooks or www.farminguk.com - The UK’s Number 1 agricultural website.