Gizzard Worm or Amidostomum Anseris are thin worms about 2cm long that predominantly affect geese. Infestations occurs directly by birds eating eggs that have been passed out in droppings so are most likely to occur when geese are kept on the same pasture.
Gizzard Worm is probably the most common form of problem in young geese as older geese build up a resistance. Gizzard worm can cause serious damage to geese and is the most common form of death in goslings.
Regular handling of goslings is highly recommended. Not only does this get them used to being handled but also allows you to ensure they are the correct weight. They should feel plump and heavy. Gizzard worm literally stops the bird from digesting its food in the gizzard so they slowly lose weight and starve to death.
Signs and symptoms
Young geese lose condition, stop putting on weight and start to lose weight. They will eventually waste away if left untreated.
Prevention is better than cure. Keeping geese on fresh pasture and worming them regularly should prevent Gizzard worms. Pay particular attention to worming young goslings around 12 weeks. As with all internal parasites, there are many treatments that will kill these worms including Leamisole and Panacur (speak to your vet about these) Flubenvet is available off the shelf without prescription and is licensed for Geese, unlike other treatments but can be tricky to give to geese that are eating a lot of grass.