Prevention and Treatment Methods for Non-Infectious Febrile Diseases in Pigs

I. Unexplained High Fever in Pigs Unexplained high fever in pigs refers to a fever syndrome of unknown cause with sudden onset, characterized by high fever (body temperature reaching as high as 40°C-42°C), reddened skin or red patches, dry hard black feces, and scant yellow urine, commonly known as "carrot disease" or "red patch disease." The disease can occur in all four seasons, and treatment with antibiotics and sulfonamides to reduce fever is very ineffective or even useless.

1. Causes A variety of causes can trigger fever, which can be clinically divided into pyrogenic fever and non-pyrogenic fever. Pyrogenic fever is caused by pyrogens such as bacteria, viruses, some parasites, proteinaceous pyrogenic substances, chemical substances, breakdown products of necrotic tissue, and antigen-antibody complexes formed in allergic reactions. Non-pyrogenic fever is mostly caused by pyrogens such as central nervous system damage and endocrine dysfunction. The so-called unexplained high fever in clinical practice is generally non-infectious; therefore, it can be considered to be mainly non-infectious pyrogenic and non-pyrogenic fever. Clinically, because the cause of some febrile diseases is unknown, they are collectively called "unexplained high fever."

2. Symptoms Sudden onset; affected pigs generally have reduced or absent appetite, are listless, with body temperature reaching above 40°C, reddened skin, sometimes with red patches, and muscle trembling; some have eye discharge, congested conjunctiva, and tearing; some have harsh panting and coughing; some have a dry snout with serous nasal discharge; some have dry hard black feces covered with white mucus or intestinal mucosa, and scant yellow urine. Affected pigs like to eat mud and drink sewage. In the early stage, treatment with antipyretics and antibiotics has some effect but is not lasting; before long the body temperature continues to rise and remains persistently high. The course of the disease is generally one to two weeks.

3. Diagnosis Clinically, it should be distinguished from high fever due to heatstroke and high fever due to damp-heat syndrome. Heatstroke fever has neurological symptoms such as unconsciousness and mania; damp-heat syndrome, by contrast, has no reddening of the skin or diarrhea.

4. Treatment For this disease, it is advisable to use Bingfeng combined with Houttuynia cordata, Andrographis paniculata, or Yandureke combined with Isatis root, Bupleurum, and other drugs for mixed intramuscular injection or alternating intramuscular injection.

II. Damp-Heat Syndrome with High Fever Damp-heat syndrome is a common condition characterized by persistent high fever that lingers, occurring mostly in the hot summer and autumn seasons.

1. Causes During the high-temperature period of summer and autumn, pig houses without heatstroke-prevention facilities, high pig density in pens, poor ventilation with damp stuffy heat, or pigs lying for long periods on damp ground or even being suddenly drenched by rain can easily trigger damp-heat high fever.

2. Symptoms Affected pigs have fever, with body temperature generally rising to around 40°C and higher in the afternoon, little sweat on the snout, listlessness; some have cold limbs and lie down more than they stand; feces are sticky and difficult to pass or slightly dry; some show symptoms such as diarrhea, vomiting, and restlessness due to pain.

3. Prevention and Treatment During the high-temperature season, attention should be paid to keeping pens dry and well ventilated, avoiding direct sunlight and rain. For affected pigs, Bingfeng, vitamin C, Andrographis paniculata, or Yandureke and Houttuynia cordata injection can be used for mixed intramuscular injection or alternating intramuscular injection.

III. High Fever from Heatstroke Heatstroke is the collective term for sunstroke and heatstroke; it is a disease characterized by acute excessively high body temperature caused by increased heat production or reduced heat dissipation. It is caused by factors such as narrow pig houses, excessive crowding of pigs, excessively high outside temperature, excessively high relative humidity, and insufficient drinking water. The main symptoms are: weak limbs, unsteady gait, dry skin, elevated body temperature, rapid breathing, accelerated heartbeat, and mania; in severe cases, the animal finally falls into coma, convulses, and dies.

Treatment measures: First move the affected pig to a ventilated, cool place and bleed it from the tips of the ears and tail (commonly known as "bleeding for sha"); then inject caffeine sodium benzoate to strengthen the heart; use glucose saline to treat dehydration, adding chlorpromazine to lower temperature and reduce agitation; use dexamethasone to prevent pulmonary edema. Author's affiliation: Government of Yankoupu Town, Shaoyang County, Hunan Province