Fighting Parasites with Fungus

Fighting Parasites with Fungus

Reading Time: 5 minutes

A number of strategies beyond deworming can help prevent parasites before they gain a foothold. Two of these will be covered in this article: pasture management and a product called BioWorma. 

By Cheryl K. Smith  One of the top healthcare concerns of goat owners is internal parasites. For years, the common wisdom was to treat goats routinely — often four times a year — with anthelmintics (dewormers), as well as to rotate those dewormers. Both strategies have since been found to be harmful, leading to parasite resistance. 

Doing fecal float tests versus routinely medicating costs less in the long run because unwarranted use of costly medicine is avoided. In addition, it helps minimize times when dewormer residues require that milk be withheld or the goat not sold for meat. Problem goats can be identified, and treatment directed only to them. 

A number of strategies beyond deworming can help prevent parasites before they gain a foothold. Two of these will be covered in this article: pasture management and a product called BioWorma. 

[optin-monster-shortcode id=”hxluox9yesmfda3ovt6w”]

Pasture Management 

Pasture management, including rotating pastures, will help control parasite overload. To understand how this works, it helps to know about the lifespan of parasites. 

Parasites that infect goats pass their eggs in manure, which winds up on the pasture. The eggs hatch into larvae in two days to a week, depending on the type of worm. They can live there for a month to six months, also depending on the type of worm. Goats grazing the pasture eat these larvae, and the cycle continues as they produce eggs in two to seven weeks, and the pasture is reinfected through their manure. These parasites particularly like wet and warm weather. 

An example is the barber pole worm — one of the most insidious. It hatches in four to six days, can live for two to four weeks on the ground, and starts producing eggs in the goat in three weeks. 

Pasture management encompasses several different approaches. First, because they don’t share parasites, other mammals besides goats can be co-pastured or rotated through different pastures at different times, helping each other. So cows, pigs, or horses can graze with or after goats (not sheep; they share parasites with goats). According to The National Center for Appropriate Technology (NCAT), the optimal stocking rate for goats and cows grazing on the same pasture is one-to-one. However, even those who have a herd of goats but just one or two cows will benefit when cows eat some of the barber pole larvae on the pasture. 

Because they don’t share parasites, other mammals besides goats can be co-pastured.

A second approach to pasture management, particularly for those with limited property, is to fence off or use moveable electric netting to confine goats in limited areas at different times. To keep barber pole worms at bay, goats need to be moved to a new area every four days during higher-risk times (spring and fall or during rainy weather). Ideally, each pasture should be allowed to rest from 40–60 days before re-grazing. If goats must graze, wait until later in the day when dew or rain has dried up, and do not cut grass too short (6–8 inches is best). 

Tips for Limiting Parasites 

Other strategies related to pasturing are listed below, and for those who want to take a deeper dive into the subject of pasture and ruminant parasite control, NCAT’s ATTRA Sustainable Agriculture section on sheep and goats has a variety of information. 

  • Keep pastures no lower than 6-8 inches. 
  • Do not use chemicals of any kind on pasture. 
  • Plant tannin-producing plants
  • Clean water tanks and eliminate standing water. 
  • Keep deer out of pastures to avoid transmission of meningeal worms
  • Designate a dry area to keep goats off pasture when needed. 
  • Lime the barn after mucking
  • Create a “beneficial plants” paddock to use during heavy parasite seasons. 


BioWorma is a new product that can be used in conjunction with pasture rotation and decrease the need for deworming even more. BioWorma is a feed additive that contains the fungus Duddingtonia flagrans. It targets the gastrointestinal nematodes barber pole worm or wire worm (Haemonchus spp.), black scour worm or hairworm (Trichostrongylus spp.), brown stomach worm (Teladorsagia (Ostertagia) spp.), nodule worm (Oesophagostomum spp.), thread-necked intestinal worm (Nematodirus spp.), and hookworm (Bunostomum spp.) in goats. This product is sold in the U.S. under the brand names BioWorma or Livamol. 

BioWorma can be mixed with regular feed; Livamol is a feed supplement that is premixed with BioWorma and then top-dressed over feed. If animals are fed grain, Livamol may be the better choice because it can be used selectively on the feed of susceptible goats. 

The fungus is naturally found in soil and pastures. It is harmless to goats, avoiding the digestive process and passing through in manure. There, it consumes parasite larvae and then dies. It is most effective at over 40 degrees Fahrenheit, so it’s best used in colder climates in the spring, summer, and early fall. The products are safe for pregnant animals, as well. 

BioWorma works by reducing the number of parasite larvae that are released onto the pasture from manure. Mycelium from the fungus that has survived digestion grows in the manure, and captures, paralyzes, and ingests the emerging worm larvae. These larvae are normally the source of infection or reinfection with parasites. Beneficial animals such as earthworms, soil nematodes, dung beetles, and soil bacteria are unaffected. 

Steps for using BioWorma include deworming goats with a chemical dewormer, moving them to a pasture with low infestation (not grazed by goats for at least six weeks), and feeding the product daily for 60 days. Spring is the ideal time to begin. 

If you have a large herd, not all goats need to be treated. Newly freshened does and growing kids are the most prone to worm infestation, so they should be the focus of treatment. Interestingly, according to one research paper, a higher dose of BioWorma is required to control parasites in goats than in sheep. 

Those who are raising goats on pasture and have the space to rotate their grazing areas are in a good position to succeed with this promising new method for preventing intestinal parasites. 


Cheryl K. Smith has been raising miniature dairy goats in the Coast Range of Oregon since 1998. She is managing editor of Midwifery Today magazine, and the author of Goat Health Care, Raising Goats for Dummies, Goat Midwifery, and several e-books related to goats. She is currently working on a cozy mystery set on a dairy goat farm. 

Originally published in the May/June 2023 issue of Goat Journal and regularly vetted for accuracy.

Leave a Reply

Your email address will not be published. Required fields are marked *