Gastrointestinal Strongyles in Llamas: Common Worm Infections and Parasite Control

Gastrointestinal strongyles are a group of parasitic roundworms that live in the stomach compartments or intestines of llamas. In camelids, these parasites often overlap with the same trichostrongyle-type worms seen in small ruminants, including Haemonchus contortus and other stomach or intestinal nematodes. Some species mainly reduce nutrient absorption, while others feed on blood and can cause severe anemia.

Many infected llamas do not look sick at first. That is part of what makes these parasites challenging for pet parents and herd managers. A llama may continue eating and acting fairly normal while slowly losing condition, shedding eggs onto pasture, and exposing herd mates.

The biggest concern is that parasite disease in llamas is not only about the worms themselves. It is also about how many worms are present, whether the animal is young or stressed, and whether the parasites are resistant to common dewormers. Because resistance is a growing problem in camelids, your vet may recommend a more targeted, test-based approach instead of routine whole-herd deworming on a fixed schedule.

Llamas usually become infected by grazing or eating feed contaminated with infective larvae from manure. Eggs passed in feces develop on pasture, especially when moisture and moderate temperatures help larvae survive. Overgrazed areas, crowded pens, and feeding directly on contaminated ground can all increase exposure.

Common strongyle-type parasites in camelids include Haemonchus, Teladorsagia/Ostertagia, and Trichostrongylus. These worms affect the digestive tract in different ways. Some irritate the stomach or intestines and reduce digestion, while blood-feeding species can cause major blood loss and low protein levels.

Risk is often highest in crias, juveniles, newly transported animals, pregnant or lactating females, and llamas sharing pasture with other susceptible species. Another major cause of ongoing problems is anthelmintic resistance, meaning the worms survive medications that used to work well. That is why repeated deworming without testing can make long-term control harder, not easier.

Your vet will usually start with a physical exam, body condition score, mucous membrane color check, and a discussion of pasture use, stocking density, recent deworming history, and herd-level illness patterns. In llamas with suspected blood-feeding worms, checking for anemia is especially important.

Fecal testing is a key part of diagnosis, but it has limits. A fecal flotation or quantitative fecal egg count can help estimate parasite shedding, yet egg counts do not always match the exact worm burden in the body. Some camelid parasites, including whipworms, may be underdetected on routine testing, so your vet interprets results alongside the llama's clinical signs.

If your llama seems weak or pale, your vet may recommend blood work such as packed cell volume and total protein to look for anemia and protein loss. In herd situations, your vet may also suggest testing several animals, then repeating fecal egg counts after treatment to see whether the chosen dewormer actually worked. That follow-up step can help identify drug resistance and guide a smarter parasite-control plan.

Prevention works best when it combines monitoring, selective treatment, and pasture hygiene. Instead of deworming every llama on a fixed calendar, many herds do better with targeted treatment based on fecal egg counts, body condition, and anemia checks. This helps reduce unnecessary drug use and may slow resistance.

Good pasture management matters. Avoid overstocking, reduce grazing pressure on short pasture, keep hay and feed off the ground when possible, and remove manure from small pens and high-traffic areas regularly. If llamas share land with sheep or goats, ask your vet how that changes parasite risk, because cross-species exposure can increase pasture contamination.

Routine observation is also part of prevention. Watch for subtle weight loss, poor fiber, pale eyelids, or animals that separate from the herd. Young llamas and animals under stress often need closer follow-up. Your vet may recommend seasonal fecal monitoring, strategic rechecks after treatment, and a herd-specific parasite plan that changes with climate, stocking density, and prior resistance patterns.

Because no single dewormer or schedule works for every farm, the safest long-term approach is a custom parasite-control program built with your vet. That plan can balance conservative care, practical herd management, and more advanced testing when needed.