Controlling parasites in goats requires a general knowledge of the types of parasites they are exposed to, how they are exposed, and how you the producer can best rid your animals of them. The goal is not necessarily to be parasite free, as they will stimulate some immune response to their presence, but rather to manage goats in a way that will keep them from being compromised by an excessive load. Parasites get their nutrition from their host, feeding on fluids and serum and blood from the goat and the groceries meant for the goat. They are internal and external, and they can be found in most animals.
How do you develop a strategy for controlling parasites in goats? You must know the enemy! Three general classes of parasites must be considered: internal intestinal worms, external parasites of the skin, and the protozoa parasites of the intestinal tract. Some have direct life cycles, meaning that eggs passed in the goat feces can infect another goat upon consumption. Others use an intermediate host for passage and development. They thrive under certain conditions and lurk in locations ready to infest your goats. Some are very resistant to environmental conditions. Some are very resistant to drugs. I recommend a program designed to avoid infestation and diminish their population.
The young kid is exposed to intestinal parasites as soon as it enters the environment that other goats have been living in. Manure from other goats will have eggs of nematodes or nematode larvae ready to enter the baby kid as it noses and nurses on its mother or nibbles and picks at the ground. One of the first parasites to infest the young baby will likely be coccidia. Most goats have some. Most adults have an immune system that recognizes coccidia and keeps it in check. It is important to understand that the dam, however, will shed more parasite eggs or ova near the time that she kids, in part due to hormonal changes that trigger an awakening from hypobiosis (like hibernation for parasites), and in part to stress. Thus, Mom is the first source for parasites for most kids.
Deworming the dam about four weeks before kidding helps to decrease the parasite load she will contribute to the environment.
Kids reared by hand will probably need to be fed a coccidiastatic drug to keep them from developing an overabundance of these intestinal protozoa. Deccox may be added to milk or feed to help. Albon or Corrid are other products.
As the kids approach their first month, deworming against nematodes should be considered. With most kids being born in the milder and wetter months, most kids will need to be dewormed monthly for the first three months.
As you build your herd strategy for control of parasites, consider how to hit ’em when it hurts the most! Using help from the weather, deworm when the weather hot and dry or when it is very cold. The residual load in the environment will be at its lowest at those times, and minimizes re-infestation. Parasites love the mild moist and balmy spring and early fall. Coccidia especially loves the spring with all the new kids in the population, and can survive for months in and around moist areas. Even just the little bit of moisture that seems to stay around a bucket or water tank will harbor them.
When moving to a clean pasture or pen, maximize control by deworming before the animals are moved. Fecal egg output will decreased. Clean old bedding out of pens and sheds before housing kids in them. Place water containers through a fence panel or elevated enough that feces cannot fall into them. Goats prefer to eat from elevated positions, not on the ground, so placement of feeders and hay mangers three feet above ground level also minimizes contamination.
During the winter months, and coming into spring we seem to see more ectoparasites. Lice are especially problematic in closely confined goats. There are biting and sucking lice, and they will cause as much stress and debilitation to an infested animal as a good load of worms. Some systematic dewormers of the Ivermectin and related drugs will take care of them while you are treating for the internal parasites. Pour on products will often be effective on the external parasites, but the absorption rate is not always appropriate for internal worms.
Involve your veterinarian in your program. Periodic fecal exams done by a veterinarian will help you to evaluate the effectiveness of your program. Because many of the drugs used for management of parasites are off-label for goats, consult with your veterinarian to establish a vet/client/patient relationship. Some recommended drug doses to consider may be found at these websites www.luresext.edu/goats/library/field/dawson02b.pdf, or www.rmncsba.org/SMALLRUMINANT.pdf.