Diagnosis and Prevention and Treatment Methods for Chronic Mycotoxin Poisoning in Pigs

A disease characterized primarily by acute conjunctivitis and diarrhea in finishing pigs and sows occurred at a large pig farm, with a morbidity rate of 20%, a mortality rate of 0.5%, and a culling rate of 1.2%. Based on clinical symptoms, pathological necropsy findings, and medical history investigation, it was diagnosed as mycotoxin poisoning in pigs. The report is as follows.

1 Clinical symptoms

Finishing pigs and sows developed acute conjunctivitis, with eyelid swelling, conjunctival hyperemia, photophobia, and mucopurulent discharge. In cases with a longer disease course, corneal opacity and blindness occurred, along with diarrhea; the feces changed from initially gruel-like to watery, and finally to thin feces containing mucus and blood, as well as undigested feed. Body temperature was normal, and appetite was slightly reduced or completely lost. Some entire litters of suckling piglets also had diarrhea, and individual growing pigs showed neurological symptoms such as opisthotonus; in some cases, the labia were red and swollen, and dark yellow urine was excreted. The disease course was 10 to 15 days. Growing pigs grew slowly, and sows often developed agalactia syndrome.

2 Pathological changes

The skin of the whole body was pale; the liver was enlarged and brittle, with uneven color; the kidneys had diffuse hemorrhage; the lymph nodes were edematous; there was fluid accumulation in the thoracic and abdominal cavities; the spleen had hemorrhagic infarction; the myocardium was soft and pale, with poor blood clotting. The gastrointestinal tract showed catarrhal hemorrhagic inflammatory changes, the bladder contained tea-colored urine, and the meninges were edematous and hyperemic.

3 Diagnosis

Based on the medical history investigation, the farm had been feeding old corn supplied by a grain depot (moldy corn that had been dried and stored for five to six years), while piglets fed new corn showed no disease. Combined with clinical symptoms and necropsy changes, it was diagnosed as chronic mycotoxin poisoning.

4 Prevention and control

Feeding of the old corn was stopped immediately and switched to new corn. Sodium sulfate and sodium bicarbonate were added to the feed of all affected pig herds, along with mequindox powder. For individual severe cases, treatments such as fluid infusion, cardiac support, detoxification, and antibiotics could be used. After 7 days, the condition was effectively controlled.