Read the questions and answers below to become informed about this parasite. Meningeal worm is a great concern to alpaca owners in areas, particularly in the North Eastern states, where white-tailed deer have a heavy population. Although we have white-tailed deer in Massachusetts, luckily this doesn't seem to be a very large problem here. There has been no evidence of Meningeal Worm on the island of Martha's Vineyard. First, you must reside in an area where white-tailed deer exist.
The larvae are coughed up and swallowed by the deer. The larvae are then passed to the feces and excreted onto the ground. The alpaca then may inadvertently ingest the snail when browsing and become infected. The larvae find an intermediate host in snails and slugs. Once the larvae are in the stomach, they penetrate the stomach wall and enter spinal nerves. Then they travel to the spinal cord or brain, migrating into the central nervous system causing neurological abnormalities in the alpaca. The disease cannot be passed without the ingestion of an infected snail or slug. Some of the symptoms seen might be: Staggering, rear leg weakness, lameness, uncoordinated gait, stiffness, paraplegia, paralysis, circling, abnormal head tilt, blindness, gradual weight loss, inability to eat. Damage to the central nervous system can be severe enough to cause death, if aggressive treatment is not begun immediately. There is no definitive way to detect it in a live animal.
Usually, some type of dewormer is used to kill the parasite. Steroids and anti-inflammatories are used to prevent inflammation and swelling from damaging the spinal cord. Supportive care is, also, used in the form of physical therapy. Keeping blood flow to muscles by massaging helps keep them healthy and allows the animal to recover better. Once the larvae migrate into the nervous tissue, any damage that occurs is usually irreversible. Can an infected alpaca pass the meningeal worm to other alpacas? Your alpaca must ingest an infected snail or slug to get m. The larvae in alpacas do not mature and produce eggs that mature into larvae that pass out of the animal. The current practice has been to give a dose of Ivermectin every 30 days to alpacas in areas with white-tailed deer. However, overuse of Ivermectin has resulted in increasing drug resistance among parasites in alpacas. Your worming program should be tailored to your individual farm and geographic area. You can put up a deer-proof fence with a gravel or paved area along the outside of the fence to attempt to keep snails and slugs out of your pastures. You can use a molluscicide, but it might be poisonous to your alpacas, so be careful. Your vet should have up-to-date information to prevent meningeal worm infections. Controlling The Parasite Problem : As part of preventive health maintenance for alpacas, owners de-worm them with various medications on a proper deworming schedule. Controlling the number of eggs and infective larva that a alpaca consumes is the starting point of any effective de-worming program. The de-worming schedule is important as well as the type and dosage of medication administered. Ideally deworming is administered to those alpaca that have the need for it. Knowing this would be the result of ongoing fecal sampling/testing. We are increasingly diagnosing resistance among intestinal parasites in llamas and alpacas. We recommend doing a follow-up fecal exam 2 weeks after treatment to confirm that the treatment has worked. A fecal egg count reduction test (checking the parasite egg count before and 14 to 21 days after de-worming medication is given) allows evaluation of de-worming efficacy.
We expect to see >90 % egg reduction if successful.
These tests can be done using the Modified Stoll's Fecal Test. This is the only test available sensitive enough to detect the low egg counts expected after de-worming. When de-worming, the entire herd could receive the medication - except for those females that are within 30 days of birthing or within 30 days of breeding. (Females in this stage should not receive any medications.) Then after approximately three days the pastures should be cleaned of the manure on the ground to prevent the alpacas from re-infecting themselves with parasite eggs in the pasture. The eggs take 3-4 days to mature so you have that length of time to remove manure from the contaminated pastures.