Hematopinus suis, or the pig louse, is a parasite that affects swine. It attaches itself to the pig generally around the head and neck area, around the jowls as well as inside the legs. With its sharp mouth, it bites into the pig, where it feeds on the blood. They can be found on pigs of any age, from the piglets to the adults.
Though they are small, pig lice are easy to spot as long as you know what you are looking for. They are visible to the naked eye. Pig lice are about 1/16th of an inch long, and are brown or gray, with some black along the outer edge. The eggs they lay, which can be as many as four per day, can be seen at the base of hairs.
Pig lice can spread very quickly through a herd, as their method of transfer is through pig-to-pig contact. This means that if only one of your pigs has pig lice, it can spread it to another, whether that is a sow passing them on to her young, or pigs passing them along as they bump into one another. Within a very short period, you could have an infestation.
Although pig lice canít live away from their host for very long, it is possible for a louse to live on a fence or side of a barn for up to two days. If another pig were to come into contact with that fence, there is a good chance that the louse will attach itself to a new host.
If you are going to bring new pigs into a herd, it is imperative that you check them for a number of diseases as well as pig lice, as this can quickly decimate a herd. Fortunately, this is something that can be controlled as long as you quarantine the new animals before they have any contact with your herd. Make sure they are one hundred percent healthy before they become part of your group.
Determining if youíre herd is suffering from an infestation of pig lice is easy as long as you know for what you should be watching.
One of the signs that you might want to look out for is the pigs rubbing and scratching against posts, fences, or feeders. The lice cause itching, and this is how pigs try to relieve themselves. Pigs will do this scratching from time to time anyway, but you should look to see if the behavior is excessive, and if the pigs appear to be stressed in any way. Since the pig lice often congregate around the head and jowls, look for the pigs to be rubbing these areas. A quick examination of several of your pigs is also a quick indicator of whether or not they have pig lice.
If you find that several of your herd does have pig lice, you need to treat the entire herd, not just the pigs that are infected. You should also treat and clean the area in which the pigs are kept.