(We do not have Meningeal worm in Western Canada yet)

With internal parasites, an ounce of prevention is worth a pound of cure … as the old saying goes. Let good herd management be your primary prevention starting first with a good nutritional program and awareness of the overall health of your animals. Parasites are more likely to seek out and attack weak or failing animals. Good sanitation, pasture rotation, and the weather also play a big part in the control of parasites on your farm. A word of caution - most veterinarians do not recommend giving any kind of deworming within 60 days after breeding or within 60 days before a birth.

Signs of internal parasites may be a general lethargy, weight loss, a depressed stance with a humped back, and ball or ploppy stools rather than pellets. However, soft stools can also be a result of a change in diet, the new fresh green pastures, or stress, so it is recommended that a fecal sample be taken to your veterinarian for examination twice a year.

Internal parasite contamination starts when an infected animal defecates and animals grazing on overcrowded pastures near dung piles injest the worm eggs. Control depends on the population numbers in your pastures, sanitation, and the weather conditions present. Clean areas regularly, especially in shaded, wet areas and feed in off-ground feeders and away from manure piles. Parasitic larva in manure in the sunlight dries out whereas larva in manure in moist, damp, dark areas survives for months. When deworming takes place, deworm all llamas on the farm. After deworming, turn the animals back out onto a clean pasture. The eggs take 3-4 days to mature so you have that length of time to remove manure from the contaminated pastures and barn areas and greatly decrease the chances of new infections.

Some infective larva, such as Nematodirus and Trichurs, can even become dormant over the winter surviving temperatures to 20 below zero and become infective again about one month after pastures begin new growth in April and May. For this reason, only third generation wormers which are larvacidal are recommended - such as Ivermectin, Oxbendazole (Synanthic), and Albendazole (Valbazen). Panacur is only effective for adult worms and does not effect the larva. These wormers should be used especially for the last worming right after the first frost in the winter and again in the spring at the time of new grass growth. It may be necessary to deworm again 30-40 days after the growth of new pastures. Injectible Ivermectin is mainly effective on Brown Stomach Worms and Meningeal Worm. Both Valbazen and Synanthic address Nematodirus and Trichurs.

Dr. Norman Evans of Madisonville, KY recommends a strategic de-worming program for this part of the country based on the life cycle of the various parasites rather than just de-worming periodically by the calendar. He suggests doing a fecal exam in the spring and a possible deworming schedule as follows: May 15 to June 1 - Valbazen at 4 ml/100 lb. BW; August 1 - Synanthic 2cc/100 lb. (22%); October 1 - Valbazen at 4ml/100 lb. BW, Panacur (3 times cattle dose), or Ivomec 1cc/100 lb. BW; December 1 - Ivomec 1 cc/100 lb. If your farm has a number of visiting animals in and out for outside breedings, 4-H animals coming and going, or crowded pastures, it may be necessary to use a more aggressive deworming program.

Meningeal Worm - the dreaded “M” word! Although luckily, this doesn’t appear to be too common in Indiana, it definitely is a concern and has found to be quite prevalent in some surrounding states. A natural parasite in the white-tailed deer, this should be suspected wherever white-tailed deer graze. The worm is passed through the feces of an infected deer, then develops in a snail which may be ingested by your llama. The larvae cause a sever reaction in the spinal cord which causes neurologic abnormalities in the llama. Signs include loss of muscle control, incoordination, dragging of limbs, blindness, paralysis, and sometimes leads to death. Immediate, aggressive treatment of injectible Ivomec and Banamine is the treatment … Call your vet! Some breeders in areas with a high density of white-tailed deer deworm monthly with Ivermectin as a preventive. Meningeal worm cannot be detected in fecal samples and is found more frequently during winter months. It has been discovered that these infected snails and slugs may winter under the large, round hay bales in the pasture and then are easily ingested by the llamas.

Coccidiosis, more common in young animals, is spread through the feces of an animal which has the disease or is a carrier, but may show no signs of illness itself. The primary sign is diarrhea. Severe cases show blood in the diarrhea, depression, and weight loss. This most commonly occurs when animals are crowded into small pens or where unsanitary conditions exist. Treatment m ay be Corid added to the drinking water and all other water sources eliminated.

Note: I’d just like to bring it to your attention that I have heard some difference of opinions on whether Valabazen should be used on pregnant females. I personally have used it successfully for three years on all my pregnant females (but never within 60 days of breeding or birthing) and have had absolutely no problems. I talked with other farms using it successfully also. Another breeder experienced some birth defects and attributes them to the use of Valbazen. One experienced veterinarian I spoke with has had no negative feed back or complaints regarding Valbazen and feels that perhaps it is the safest dewormer we have. I also spoke with Dr. Norman Evans and he reports that he has not experienced any negative effects with Valbazen. He emphasized that studies done by both him and Dr. Murray Fowler show that it greatly increases the chance of congenital birth defects (not genetic) when any de-wormer is used within 60 days after breeding. Within 15-35 days after conception the cells are already in place and organs and tissues have formed. Their studies show that especially heat, even a four degree rise in temperature, during this crucial period of development can definitely effect the fetus and increases the chance of birth defects. After 35 days of development, the fetus continues to grow but cannot change or lose something that has already developed properly. Use of a de-wormer with 60 days of birthing may cause stress and possible abortion, but not defects. The Valbazen label instructions (although like all de-wormers, not formulated for llamas) states to not use within the first 45 days of pregnancy on any animal. As always, gather as much information as possible, check with your own veterinarian, and decide what is best for your own animals.

Source: Dr. Norman Evans’ Vet Manual, Caring For Llamas by Clare Hoffman, D.V.M., Dr. Justin Janssen, D.V.M., Dr. Norman Evans, D.V.M.
 

This article appeared in the July 1997 issue of the Hoosier Hummer by Marilyn Nenni. It is not intended to be a substitute for qualified professional advice from your veterinarian.