Are Your Pigs Losing Hair? Here Are 3 Possible Causes

Are your pigs losing hair? Keep reading to find out which are the most common causes why sows and boars lose their hair. 

Hair in mammals serves several purposes. The first and probably the most important is to insulate and to protect the animal against cold.

Another important function of fur is to protect the animals' skin against UV radiation and sunburn.

Hair can also have a sensorial function. Many mammals have whiskers, which are important for tactile sensing, orientation, prey following, and more.

The hair of some mammals even serves a defensive role. For instance, porcupines have modified hairs (called quills) that protect them from predators. 

Other roles of hair:

  • Camouflage
  • Opponent intimidation
  • Communication

As you can see, hair has several important functions in mammals.

Although most domestic pig breeds do not have very dense or impressive hair, there are some hairy breeds like Kunekune, Mukota, or Gascon. There are even some woolly-coated pigs, as is Mangalitsa (or Mangalitza), a Hungarian breed of domestic pigs.

Even if most pig breeds have short and sparse hair, when it starts to fall out, this can be a sign that something is wrong.

Reasons For Pig Losing Hair

On pigs, hair loss (or alopecia) typically indicates a disorder, disease, or parasitic infection.

Depending on how much hair the animals lose and the potential symptoms that accompany this condition, we can usually identify the problem's source.

Below is a list of the most common reasons why pigs lose their hair.

1. Nutritional Deficiencies

Most often, hair loss in pigs indicates a deficiency of certain vitamins and minerals in their diets.

Biotin Deficiency

One condition that can cause hair loss in pigs is a biotin deficiency.

Biotin (also known as vitamin H, vitamin B₇, or vitamin B₈) is a part of the B complex vitamins. It has several important functions, but it especially has a vital role in metabolizing carbs, fats, and proteins from foods.

Biotin can be freely obtained from various foods. Some that contain larger higher levels of biotin include meat, fish, eggs, nuts, seeds, and several vegetables.

An alimentation consisting of biotin-rich foods is not only important for humans. Pigs also need this vitamin in their diet to stay healthy.

Biotin deficiency symptoms on pigs include excessive hair loss, dermatitis, and skin ulcerations. These are often accompanied by inflammation of the mucous membranes of the mouth, exudates around the eyes, transverse cracking of the hooves, and bleeding of the footpads [1].

Studies have shown that supplementing the swine diet with biotin can increase the insemination rate, preventing toe lesions and hair conditions [2].

Zink Deficiency (Parakeratosis)

Another common problem facing pigs is a lack of zinc, which often leads to a skin condition called Parakeratosis [3].

Swine parakeratosis is a noninfectious skin disease caused by an unbalanced diet. More precisely, not enough zinc and essential fatty acids. This is often supplemented by a diet too rich in calcium, which can reduce zinc absorption.

The incipient symptoms of parakeratosis on pigs include a reduced appetite, failure to grow normally, oftentimes episodes of diarrhea, skin lesions, and hair loss.

This condition is initially observed by the skin's reddening on the underline, accompanied by poxlike spots on the belly and on the medial thighs. The lesions will then appear on the limbs, tail, ears, and, in severe cases, cover the whole body, producing large folds or wrinkles on the skin [4].

Growing piglets between 2 and 4 months of age seem to be more frequently affected by parakeratosis.

Other vitamins that influence hair growth are B complex, A, and C, while the most important minerals for hair are zinc, magnesium, iron, copper, silicon, selenium, and calcium.

2. Sarcoptic Mange

Pig mange is a parasitic skin disease caused by mites.

In swine, this disease is caused by either Sarcoptes scabiei var. suis (sarcoptic mange, or scabies) or Demodex phylloides (demodectic mange) [5]

Demodectic mange is not related to sarcoptic mange and compared to the sarcoptic mange, it's relatively insignificant.

Sarcoptic mange is the most severe parasitic disease of pigs. This parasitic infection is highly contagious, with acute or chronic evolution. It manifests by intense itching, hair loss, blisters and pustules, dermatitis, and weight loss.

Constant rubbing and scratching are the most common indications of scabies. Yet, if a pig rubs frequently, it is not enough to say that it suffers from scabies without a thorough check. The disease can be proved if mites' presence is confirmed in skin scrapings or in the exudate taken from the external auditory canal.

3. Some Pig Breeds Blow Their Coat

Although most pigs do not change their hair, some breeds of pigs shed their coat. In pigs, this process is called "coat blowing."

Mainly, miniature pig breeds are the ones that blow their coat (potbelly pigs, KuneKune, etc.).

This may surprise people who have never cared for pigs in one of these miniature breeds. When their piglets begin to lose their hair, many of them start panicking and seek the help of a veterinarian.

However, it's perfectly normal for some breeds to change their coat once or twice a year.

The shedding process is different in pigs than in dogs and cats. While cats and dogs gradually change their fur after growing the new hair, pigs that shed can lose their hair in large patches before their new coat grows.

Most pig breeds that blow their coat have two major shedding periods. One in the spring and one in the fall. Pigs that live outdoors typically change their winter coats in May to June to get ready for summertime.

However, the coat blowing cycles of pigs are not fixed and may vary from one breed to another, on climate and other factors. Also, pig living indoors may change their hair at a different date than the ones raised outside.

It is perfectly normal for some pigs to lose almost all their hair before growing another one.

Final Word

While hair loss in some pig breeds is normal, being a way for them to change their winter fur for summer fur and vice versa, when hair loss is accompanied by other symptoms, skin blemishes, excessive scratching, or a visible state of stress of the animal, it is necessary to consult a veterinarian.

Infections with certain parasites or the lack of specific vitamins and minerals are most often responsible for hair loss in pigs.


  1. Nutritional Diseases of Pigs
  2. Biotin in swine nutrition
  3. Swine Diseases
  4. Parakeratosis: A Nutritional Disease of Swine
  5. Mange (Sarcoptic Mange)